diff --git a/src/parser/ArcanistBundle.php b/src/parser/ArcanistBundle.php
index 7ec8b89d..399ff611 100644
--- a/src/parser/ArcanistBundle.php
+++ b/src/parser/ArcanistBundle.php
@@ -1,956 +1,1006 @@
 <?php
 
 /**
  * Converts changesets between different formats.
  */
 final class ArcanistBundle extends Phobject {
 
   private $changes;
   private $conduit;
   private $blobs = array();
   private $diskPath;
   private $baseRevision;
   private $revisionID;
   private $encoding;
   private $loadFileDataCallback;
   private $authorName;
   private $authorEmail;
 
   public function setAuthorEmail($author_email) {
     $this->authorEmail = $author_email;
     return $this;
   }
 
   public function getAuthorEmail() {
     return $this->authorEmail;
   }
 
   public function setAuthorName($author_name) {
     $this->authorName = $author_name;
     return $this;
   }
 
   public function getAuthorName() {
     return $this->authorName;
   }
 
   public function getFullAuthor() {
     $author_name = $this->getAuthorName();
     if ($author_name === null) {
       return null;
     }
 
     $author_email = $this->getAuthorEmail();
     if ($author_email === null) {
       return null;
     }
 
     $full_author = sprintf('%s <%s>', $author_name, $author_email);
 
     // Because git is very picky about the author being in a valid format,
     // verify that we can parse it.
     $address = new PhutilEmailAddress($full_author);
     if (!$address->getDisplayName() || !$address->getAddress()) {
       return null;
     }
 
     return $full_author;
   }
 
   public function setConduit(ConduitClient $conduit) {
     $this->conduit = $conduit;
     return $this;
   }
 
   public function setBaseRevision($base_revision) {
     $this->baseRevision = $base_revision;
     return $this;
   }
 
   public function setEncoding($encoding) {
     $this->encoding = $encoding;
     return $this;
   }
 
   public function getEncoding() {
     return $this->encoding;
   }
 
   public function getBaseRevision() {
     return $this->baseRevision;
   }
 
   public function setRevisionID($revision_id) {
     $this->revisionID = $revision_id;
     return $this;
   }
 
   public function getRevisionID() {
     return $this->revisionID;
   }
 
   public static function newFromChanges(array $changes) {
     $obj = new ArcanistBundle();
     $obj->changes = $changes;
     return $obj;
   }
 
   private function getEOL($patch_type) {
     // NOTE: Git always generates "\n" line endings, even under Windows, and
     // can not parse certain patches with "\r\n" line endings. SVN generates
     // patches with "\n" line endings on Mac or Linux and "\r\n" line endings
     // on Windows. (This EOL style is used only for patch metadata lines, not
     // for the actual patch content.)
 
     // (On Windows, Mercurial generates \n newlines for `--git` diffs, as it
     // must, but also \n newlines for unified diffs. We never need to deal with
     // these as we use Git format for Mercurial, so this case is currently
     // ignored.)
 
     switch ($patch_type) {
       case 'git':
         return "\n";
       case 'unified':
         return phutil_is_windows() ? "\r\n" : "\n";
       default:
         throw new Exception(
           pht("Unknown patch type '%s'!", $patch_type));
     }
   }
 
   public static function newFromArcBundle($path) {
     $path = Filesystem::resolvePath($path);
 
     $future = new ExecFuture(
       'tar tfO %s',
       $path);
     list($stdout, $file_list) = $future->resolvex();
     $file_list = explode("\n", trim($file_list));
 
     if (in_array('meta.json', $file_list)) {
       $future = new ExecFuture(
         'tar xfO %s meta.json',
         $path);
       $meta_info = $future->resolveJSON();
       $version       = idx($meta_info, 'version', 0);
       $base_revision = idx($meta_info, 'baseRevision');
       $revision_id   = idx($meta_info, 'revisionID');
       $encoding      = idx($meta_info, 'encoding');
       $author_name   = idx($meta_info, 'authorName');
       $author_email  = idx($meta_info, 'authorEmail');
     } else {
       // this arc bundle was probably made before we started storing meta info
       $version       = 0;
       $base_revision = null;
       $revision_id   = null;
       $encoding      = null;
       $author        = null;
     }
 
     $future = new ExecFuture(
       'tar xfO %s changes.json',
       $path);
     $changes = $future->resolveJSON();
 
     foreach ($changes as $change_key => $change) {
       foreach ($change['hunks'] as $key => $hunk) {
         list($hunk_data) = execx('tar xfO %s hunks/%s', $path, $hunk['corpus']);
         $changes[$change_key]['hunks'][$key]['corpus'] = $hunk_data;
       }
     }
 
     foreach ($changes as $change_key => $change) {
       $changes[$change_key] = ArcanistDiffChange::newFromDictionary($change);
     }
 
     $obj = new ArcanistBundle();
     $obj->changes = $changes;
     $obj->diskPath = $path;
     $obj->setBaseRevision($base_revision);
     $obj->setRevisionID($revision_id);
     $obj->setEncoding($encoding);
 
     return $obj;
   }
 
   public static function newFromDiff($data) {
     $obj = new ArcanistBundle();
 
     $parser = new ArcanistDiffParser();
     $obj->changes = $parser->parseDiff($data);
 
     return $obj;
   }
 
   private function __construct() {}
 
   public function writeToDisk($path) {
     $changes = $this->getChanges();
 
     $change_list = array();
     foreach ($changes as $change) {
       $change_list[] = $change->toDictionary();
     }
 
     $hunks = array();
     foreach ($change_list as $change_key => $change) {
       foreach ($change['hunks'] as $key => $hunk) {
         $hunks[] = $hunk['corpus'];
         $change_list[$change_key]['hunks'][$key]['corpus'] = count($hunks) - 1;
       }
     }
 
     $blobs = array();
     foreach ($change_list as $change) {
       if (!empty($change['metadata']['old:binary-phid'])) {
         $blobs[$change['metadata']['old:binary-phid']] = null;
       }
       if (!empty($change['metadata']['new:binary-phid'])) {
         $blobs[$change['metadata']['new:binary-phid']] = null;
       }
     }
     foreach ($blobs as $phid => $null) {
       $blobs[$phid] = $this->getBlob($phid);
     }
 
     $meta_info = array(
       'version'      => 5,
       'baseRevision' => $this->getBaseRevision(),
       'revisionID'   => $this->getRevisionID(),
       'encoding'     => $this->getEncoding(),
       'authorName'   => $this->getAuthorName(),
       'authorEmail'  => $this->getAuthorEmail(),
     );
 
     $dir = Filesystem::createTemporaryDirectory();
     Filesystem::createDirectory($dir.'/hunks');
     Filesystem::createDirectory($dir.'/blobs');
     Filesystem::writeFile($dir.'/changes.json', json_encode($change_list));
     Filesystem::writeFile($dir.'/meta.json', json_encode($meta_info));
     foreach ($hunks as $key => $hunk) {
       Filesystem::writeFile($dir.'/hunks/'.$key, $hunk);
     }
     foreach ($blobs as $key => $blob) {
       Filesystem::writeFile($dir.'/blobs/'.$key, $blob);
     }
     execx(
       '(cd %s; tar -czf %s *)',
       $dir,
       Filesystem::resolvePath($path));
     Filesystem::remove($dir);
   }
 
   public function toUnifiedDiff() {
     $eol = $this->getEOL('unified');
 
     $result = array();
     $changes = $this->getChanges();
     foreach ($changes as $change) {
 
       $hunk_changes = $this->buildHunkChanges($change->getHunks(), $eol);
       if (!$hunk_changes) {
         continue;
       }
 
       $old_path = $this->getOldPath($change);
       $cur_path = $this->getCurrentPath($change);
 
       $index_path = $cur_path;
       if ($index_path === null) {
         $index_path = $old_path;
       }
 
       $result[] = 'Index: '.$index_path;
       $result[] = $eol;
       $result[] = str_repeat('=', 67);
       $result[] = $eol;
 
       if ($old_path === null) {
         $old_path = '/dev/null';
       }
 
       if ($cur_path === null) {
         $cur_path = '/dev/null';
       }
 
       // When the diff is used by `patch`, `patch` ignores what is listed as the
       // current path and just makes changes to the file at the old path (unless
       // the current path is '/dev/null'.
       // If the old path and the current path aren't the same (and neither is
       // /dev/null), this indicates the file was moved or copied. By listing
       // both paths as the new file, `patch` will apply the diff to the new
       // file.
       if ($cur_path !== '/dev/null' && $old_path !== '/dev/null') {
         $old_path = $cur_path;
       }
 
       $result[] = '--- '.$old_path.$eol;
       $result[] = '+++ '.$cur_path.$eol;
 
       $result[] = $hunk_changes;
     }
 
     if (!$result) {
       return '';
     }
 
     $diff = implode('', $result);
     return $this->convertNonUTF8Diff($diff);
   }
 
   public function toGitPatch() {
     $eol = $this->getEOL('git');
 
     $result = array();
     $changes = $this->getChanges();
 
     $binary_sources = array();
     foreach ($changes as $change) {
       if (!$this->isGitBinaryChange($change)) {
         continue;
       }
 
       $type = $change->getType();
       if ($type == ArcanistDiffChangeType::TYPE_MOVE_AWAY ||
           $type == ArcanistDiffChangeType::TYPE_COPY_AWAY ||
           $type == ArcanistDiffChangeType::TYPE_MULTICOPY) {
         foreach ($change->getAwayPaths() as $path) {
           $binary_sources[$path] = $change;
         }
       }
     }
 
     foreach (array_keys($changes) as $multicopy_key) {
       $multicopy_change = $changes[$multicopy_key];
 
       $type = $multicopy_change->getType();
       if ($type != ArcanistDiffChangeType::TYPE_MULTICOPY) {
         continue;
       }
 
       // Decompose MULTICOPY into one MOVE_HERE and several COPY_HERE because
       // we need more information than we have in order to build a delete patch
       // and represent it as a bunch of COPY_HERE plus a delete. For details,
       // see T419.
 
       // Basically, MULTICOPY means there are 2 or more corresponding COPY_HERE
       // changes, so find one of them arbitrarily and turn it into a MOVE_HERE.
 
       // TODO: We might be able to do this more cleanly after T230 is resolved.
 
       $decompose_okay = false;
       foreach ($changes as $change_key => $change) {
         if ($change->getType() != ArcanistDiffChangeType::TYPE_COPY_HERE) {
           continue;
         }
         if ($change->getOldPath() != $multicopy_change->getCurrentPath()) {
           continue;
         }
         $decompose_okay = true;
         $change = clone $change;
         $change->setType(ArcanistDiffChangeType::TYPE_MOVE_HERE);
         $changes[$change_key] = $change;
 
         // The multicopy is now fully represented by MOVE_HERE plus one or more
         // COPY_HERE, so throw it away.
         unset($changes[$multicopy_key]);
         break;
       }
 
       if (!$decompose_okay) {
         throw new Exception(
           pht(
             'Failed to decompose multicopy changeset in '.
             'order to generate diff.'));
       }
     }
 
     foreach ($changes as $change) {
       $type = $change->getType();
       $file_type = $change->getFileType();
 
       if ($file_type == ArcanistDiffChangeType::FILE_DIRECTORY) {
         // TODO: We should raise a FYI about this, so the user is aware
         // that we omitted it, if the directory is empty or has permissions
         // which git can't represent.
 
         // Git doesn't support empty directories, so we simply ignore them. If
         // the directory is nonempty, 'git apply' will create it when processing
         // the changesets for files inside it.
         continue;
       }
 
       if ($type == ArcanistDiffChangeType::TYPE_MOVE_AWAY) {
         // Git will apply this in the corresponding MOVE_HERE.
         continue;
       }
 
       $old_mode = idx($change->getOldProperties(), 'unix:filemode', '100644');
       $new_mode = idx($change->getNewProperties(), 'unix:filemode', '100644');
 
       $is_binary = $this->isGitBinaryChange($change);
 
       if ($is_binary) {
         $old_binary = idx($binary_sources, $this->getCurrentPath($change));
         $change_body = $this->buildBinaryChange($change, $old_binary);
       } else {
         $change_body = $this->buildHunkChanges($change->getHunks(), $eol);
       }
       if ($type == ArcanistDiffChangeType::TYPE_COPY_AWAY) {
         // TODO: This is only relevant when patching old Differential diffs
         // which were created prior to arc pruning TYPE_COPY_AWAY for files
         // with no modifications.
         if (!strlen($change_body) && ($old_mode == $new_mode)) {
           continue;
         }
       }
 
       $old_path = $this->getOldPath($change);
       $cur_path = $this->getCurrentPath($change);
 
       if ($old_path === null) {
         $old_index = 'a/'.$cur_path;
         $old_target  = '/dev/null';
       } else {
         $old_index = 'a/'.$old_path;
         $old_target  = 'a/'.$old_path;
       }
 
       if ($cur_path === null) {
         $cur_index = 'b/'.$old_path;
         $cur_target  = '/dev/null';
       } else {
         $cur_index = 'b/'.$cur_path;
         $cur_target  = 'b/'.$cur_path;
       }
 
       $old_target = $this->encodeGitTargetPath($old_target);
       $cur_target = $this->encodeGitTargetPath($cur_target);
 
       $result[] = "diff --git {$old_index} {$cur_index}".$eol;
 
       if ($type == ArcanistDiffChangeType::TYPE_ADD) {
         $result[] = "new file mode {$new_mode}".$eol;
       }
 
       if ($type == ArcanistDiffChangeType::TYPE_COPY_HERE ||
           $type == ArcanistDiffChangeType::TYPE_MOVE_HERE ||
           $type == ArcanistDiffChangeType::TYPE_COPY_AWAY ||
           $type == ArcanistDiffChangeType::TYPE_CHANGE) {
         if ($old_mode !== $new_mode) {
           $result[] = "old mode {$old_mode}".$eol;
           $result[] = "new mode {$new_mode}".$eol;
         }
       }
 
       if ($type == ArcanistDiffChangeType::TYPE_COPY_HERE) {
         $result[] = "copy from {$old_path}".$eol;
         $result[] = "copy to {$cur_path}".$eol;
       } else if ($type == ArcanistDiffChangeType::TYPE_MOVE_HERE) {
         $result[] = "rename from {$old_path}".$eol;
         $result[] = "rename to {$cur_path}".$eol;
       } else if ($type == ArcanistDiffChangeType::TYPE_DELETE ||
                  $type == ArcanistDiffChangeType::TYPE_MULTICOPY) {
         $old_mode = idx($change->getOldProperties(), 'unix:filemode');
         if ($old_mode) {
           $result[] = "deleted file mode {$old_mode}".$eol;
         }
       }
 
       if ($change_body) {
         if (!$is_binary) {
           $result[] = "--- {$old_target}".$eol;
           $result[] = "+++ {$cur_target}".$eol;
         }
         $result[] = $change_body;
       }
     }
 
     $diff = implode('', $result).$eol;
     return $this->convertNonUTF8Diff($diff);
   }
 
   private function isGitBinaryChange(ArcanistDiffChange $change) {
     $file_type = $change->getFileType();
     return ($file_type == ArcanistDiffChangeType::FILE_BINARY ||
             $file_type == ArcanistDiffChangeType::FILE_IMAGE);
   }
 
   private function convertNonUTF8Diff($diff) {
     if ($this->encoding) {
       $diff = phutil_utf8_convert($diff, $this->encoding, 'UTF-8');
     }
     return $diff;
   }
 
   public function getChanges() {
     return $this->changes;
   }
 
   private function breakHunkIntoSmallHunks(ArcanistDiffHunk $base_hunk) {
     $context = 3;
 
     $results = array();
     $lines = phutil_split_lines($base_hunk->getCorpus());
     $n = count($lines);
 
     $old_offset = $base_hunk->getOldOffset();
     $new_offset = $base_hunk->getNewOffset();
 
     $ii = 0;
     $jj = 0;
     while ($ii < $n) {
       // Skip lines until we find the next line with changes. Note: this skips
       // both ' ' (no changes) and '\' (no newline at end of file) lines. If we
       // don't skip the latter, we may incorrectly generate a terminal hunk
       // that has no actual change information when a file doesn't have a
       // terminal newline and not changed near the end of the file. 'patch' will
       // fail to apply the diff if we generate a hunk that does not actually
       // contain changes.
       for ($jj = $ii; $jj < $n; ++$jj) {
         $char = $lines[$jj][0];
         if ($char == '-' || $char == '+') {
           break;
         }
       }
       if ($jj >= $n) {
         break;
       }
 
       $hunk_start = max($jj - $context, 0);
 
 
       // NOTE: There are two tricky considerations here.
       // We can not generate a patch with overlapping hunks, or 'git apply'
       // rejects it after 1.7.3.4.
       // We can not generate a patch with too much trailing context, or
       // 'patch' rejects it.
       // So we need to ensure that we generate disjoint hunks, but don't
       // generate any hunks with too much context.
 
       $old_lines = 0;
       $new_lines = 0;
       $hunk_adjust = 0;
       $last_change = $jj;
       $break_here = null;
       for (; $jj < $n; ++$jj) {
         if ($lines[$jj][0] == ' ') {
 
           if ($jj - $last_change > $context) {
             if ($break_here === null) {
               // We haven't seen a change in $context lines, so this is a
               // potential place to break the hunk. However, we need to keep
               // looking in case there is another change fewer than $context
               // lines away, in which case we have to merge the hunks.
               $break_here = $jj;
             }
           }
 
           if ($jj - $last_change > (($context + 1) * 2)) {
             // We definitely aren't going to merge this with the next hunk, so
             // break out of the loop. We'll end the hunk at $break_here.
             break;
           }
         } else {
           $break_here = null;
           $last_change = $jj;
 
           if ($lines[$jj][0] == '\\') {
             // When we have a "\ No newline at end of file" line, it does not
             // contribute to either hunk length.
             ++$hunk_adjust;
           } else if ($lines[$jj][0] == '-') {
             ++$old_lines;
           } else if ($lines[$jj][0] == '+') {
             ++$new_lines;
           }
         }
       }
 
       if ($break_here !== null) {
         $jj = $break_here;
       }
 
       $hunk_length = min($jj, $n) - $hunk_start;
       $count_length = ($hunk_length - $hunk_adjust);
 
       $hunk = new ArcanistDiffHunk();
       $hunk->setOldOffset($old_offset + $hunk_start - $ii);
       $hunk->setNewOffset($new_offset + $hunk_start - $ii);
       $hunk->setOldLength($count_length - $new_lines);
       $hunk->setNewLength($count_length - $old_lines);
 
       $corpus = array_slice($lines, $hunk_start, $hunk_length);
       $corpus = implode('', $corpus);
       $hunk->setCorpus($corpus);
 
       $results[] = $hunk;
 
       $old_offset += ($jj - $ii) - $new_lines;
       $new_offset += ($jj - $ii) - $old_lines;
       $ii = $jj;
     }
 
     return $results;
   }
 
   private function encodeGitTargetPath($path) {
     // See T8768. If a target path contains spaces, it must be terminated with
     // a tab. If we don't do this, Mercurial has the wrong behavior when
     // applying the patch. This results in a semantic trailing whitespace
     // character:
     //
     //   +++ b/X Y.txt\t
     //
     // Everyone is at fault here and there are no winners.
 
     if (strpos($path, ' ') !== false) {
       $path = $path."\t";
     }
 
     return $path;
   }
 
 
   private function getOldPath(ArcanistDiffChange $change) {
     $old_path = $change->getOldPath();
     $type = $change->getType();
 
     if (!strlen($old_path) ||
         $type == ArcanistDiffChangeType::TYPE_ADD) {
       $old_path = null;
     }
 
     return $old_path;
   }
 
   private function getCurrentPath(ArcanistDiffChange $change) {
     $cur_path = $change->getCurrentPath();
     $type = $change->getType();
 
     if (!strlen($cur_path) ||
         $type == ArcanistDiffChangeType::TYPE_DELETE ||
         $type == ArcanistDiffChangeType::TYPE_MULTICOPY) {
       $cur_path = null;
     }
 
     return $cur_path;
   }
 
   private function buildHunkChanges(array $hunks, $eol) {
     assert_instances_of($hunks, 'ArcanistDiffHunk');
     $result = array();
     foreach ($hunks as $hunk) {
       $small_hunks = $this->breakHunkIntoSmallHunks($hunk);
       foreach ($small_hunks as $small_hunk) {
         $o_off = $small_hunk->getOldOffset();
         $o_len = $small_hunk->getOldLength();
         $n_off = $small_hunk->getNewOffset();
         $n_len = $small_hunk->getNewLength();
         $corpus = $small_hunk->getCorpus();
 
         // NOTE: If the length is 1 it can be omitted. Since git does this,
         // we also do it so that "arc export --git" diffs are as similar to
         // real git diffs as possible, which helps debug issues.
 
         if ($o_len == 1) {
           $o_head = "{$o_off}";
         } else {
           $o_head = "{$o_off},{$o_len}";
         }
 
         if ($n_len == 1) {
           $n_head = "{$n_off}";
         } else {
           $n_head = "{$n_off},{$n_len}";
         }
 
         $result[] = "@@ -{$o_head} +{$n_head} @@".$eol;
         $result[] = $corpus;
 
         $last = substr($corpus, -1);
         if ($last !== false && $last != "\r" && $last != "\n") {
           $result[] = $eol;
         }
       }
     }
     return implode('', $result);
   }
 
   public function setLoadFileDataCallback($callback) {
     $this->loadFileDataCallback = $callback;
     return $this;
   }
 
   private function getBlob($phid, $name = null) {
     if ($this->loadFileDataCallback) {
       return call_user_func($this->loadFileDataCallback, $phid);
     }
 
     if ($this->diskPath) {
       list($blob_data) = execx('tar xfO %s blobs/%s', $this->diskPath, $phid);
       return $blob_data;
     }
 
     $console = PhutilConsole::getConsole();
 
     if ($this->conduit) {
       if ($name) {
         $console->writeErr(
           "%s\n",
           pht("Downloading binary data for '%s'...", $name));
       } else {
         $console->writeErr("%s\n", pht('Downloading binary data...'));
       }
       $data_base64 = $this->conduit->callMethodSynchronous(
         'file.download',
         array(
           'phid' => $phid,
         ));
       return base64_decode($data_base64);
     }
 
     throw new Exception(pht("Nowhere to load blob '%s' from!", $phid));
   }
 
   private function buildBinaryChange(ArcanistDiffChange $change, $old_binary) {
     $eol = $this->getEOL('git');
 
     // In Git, when we write out a binary file move or copy, we need the
     // original binary for the source and the current binary for the
     // destination.
 
     if ($old_binary) {
       if ($old_binary->getOriginalFileData() !== null) {
         $old_data = $old_binary->getOriginalFileData();
         $old_phid = null;
       } else {
         $old_data = null;
         $old_phid = $old_binary->getMetadata('old:binary-phid');
       }
     } else {
       $old_data = $change->getOriginalFileData();
       $old_phid = $change->getMetadata('old:binary-phid');
     }
 
     if ($old_data === null && $old_phid) {
       $name = basename($change->getOldPath());
       $old_data = $this->getBlob($old_phid, $name);
     }
 
     $old_length = strlen($old_data);
 
     if ($old_data === null) {
       $old_data = '';
       $old_sha1 = str_repeat('0', 40);
     } else {
       $old_sha1 = sha1("blob {$old_length}\0{$old_data}");
     }
 
     $new_phid = $change->getMetadata('new:binary-phid');
 
     $new_data = null;
     if ($change->getCurrentFileData() !== null) {
       $new_data = $change->getCurrentFileData();
     } else if ($new_phid) {
       $name = basename($change->getCurrentPath());
       $new_data = $this->getBlob($new_phid, $name);
     }
 
     $new_length = strlen($new_data);
 
     if ($new_data === null) {
       $new_data = '';
       $new_sha1 = str_repeat('0', 40);
     } else {
       $new_sha1 = sha1("blob {$new_length}\0{$new_data}");
     }
 
     $content = array();
     $content[] = "index {$old_sha1}..{$new_sha1}".$eol;
     $content[] = 'GIT binary patch'.$eol;
 
     $content[] = "literal {$new_length}".$eol;
     $content[] = $this->emitBinaryDiffBody($new_data).$eol;
 
     $content[] = "literal {$old_length}".$eol;
     $content[] = $this->emitBinaryDiffBody($old_data).$eol;
 
     return implode('', $content);
   }
 
   private function emitBinaryDiffBody($data) {
     $eol = $this->getEOL('git');
+    return self::newBase85Data($data, $eol);
+  }
 
-    if (!function_exists('gzcompress')) {
-      throw new Exception(
-        pht(
-          'This patch has binary data. The PHP zlib extension is required to '.
-          'apply patches with binary data to git. Install the PHP zlib '.
-          'extension to continue.'));
-    }
-
-    // See emit_binary_diff_body() in diff.c for git's implementation.
+  public static function newBase85Data($data, $eol, $mode = null) {
+    // The "32bit" and "64bit" modes are used by unit tests to verify that all
+    // of the encoding pathways here work identically. In these modes, we skip
+    // compression because `gzcompress()` may not be stable and we just want
+    // to test that the output matches some expected result.
 
-    $buf = '';
+    if ($mode === null) {
+      if (!function_exists('gzcompress')) {
+        throw new Exception(
+          pht(
+            'This patch has binary data. The PHP zlib extension is required '.
+            'to apply patches with binary data to git. Install the PHP zlib '.
+            'extension to continue.'));
+      }
 
-    $deflated = gzcompress($data);
-    $lines = str_split($deflated, 52);
-    foreach ($lines as $line) {
-      $len = strlen($line);
-      // The first character encodes the line length.
-      if ($len <= 26) {
-        $buf .= chr($len + ord('A') - 1);
-      } else {
-        $buf .= chr($len - 26 + ord('a') - 1);
+      $input = gzcompress($data);
+      $is_64bit = (PHP_INT_SIZE >= 8);
+    } else {
+      switch ($mode) {
+        case '32bit':
+          $input = $data;
+          $is_64bit = false;
+          break;
+        case '64bit':
+          $input = $data;
+          $is_64bit = true;
+          break;
+        default:
+          throw new Exception(
+            pht(
+              'Unsupported base85 encoding mode "%s".',
+              $mode));
       }
-      $buf .= self::encodeBase85($line);
-      $buf .= $eol;
     }
 
-    return $buf;
-  }
+    // See emit_binary_diff_body() in diff.c for git's implementation.
 
-  public static function encodeBase85($data) {
     // This is implemented awkwardly in order to closely mirror git's
     // implementation in base85.c
 
     // It is also implemented awkwardly to work correctly on 32-bit machines.
     // Broadly, this algorithm converts the binary input to printable output
     // by transforming each 4 binary bytes of input to 5 printable bytes of
     // output, one piece at a time.
     //
     // To do this, we convert the 4 bytes into a 32-bit integer, then use
     // modulus and division by 85 to pick out printable bytes (85^5 is slightly
     // larger than 2^32). In C, this algorithm is fairly easy to implement
     // because the accumulator can be made unsigned.
     //
     // In PHP, there are no unsigned integers, so values larger than 2^31 break
     // on 32-bit systems under modulus:
     //
     //   $ php -r 'print (1 << 31) % 13;' # On a 32-bit machine.
     //   -11
     //
     // However, PHP's float type is an IEEE 754 64-bit double precision float,
     // so we can safely store integers up to around 2^53 without loss of
     // precision. To work around the lack of an unsigned type, we just use a
     // double and perform the modulus with fmod().
     //
     // (Since PHP overflows integer operations into floats, we don't need much
     // additional casting.)
 
+    // On 64 bit systems, we skip all this fanfare and just use integers. This
+    // is significantly faster.
+
     static $map = array(
       '0',
       '1',
       '2',
       '3',
       '4',
       '5',
       '6',
       '7',
       '8',
       '9',
       'A',
       'B',
       'C',
       'D',
       'E',
       'F',
       'G',
       'H',
       'I',
       'J',
       'K',
       'L',
       'M',
       'N',
       'O',
       'P',
       'Q',
       'R',
       'S',
       'T',
       'U',
       'V',
       'W',
       'X',
       'Y',
       'Z',
       'a',
       'b',
       'c',
       'd',
       'e',
       'f',
       'g',
       'h',
       'i',
       'j',
       'k',
       'l',
       'm',
       'n',
       'o',
       'p',
       'q',
       'r',
       's',
       't',
       'u',
       'v',
       'w',
       'x',
       'y',
       'z',
       '!',
       '#',
       '$',
       '%',
       '&',
       '(',
       ')',
       '*',
       '+',
       '-',
       ';',
       '<',
       '=',
       '>',
       '?',
       '@',
       '^',
       '_',
       '`',
       '{',
       '|',
       '}',
       '~',
     );
 
+    $len_map = array();
+    for ($ii = 0; $ii <= 52; $ii++) {
+      if ($ii <= 26) {
+        $len_map[$ii] = chr($ii + ord('A') - 1);
+      } else {
+        $len_map[$ii] = chr($ii - 26 + ord('a') - 1);
+      }
+    }
+
     $buf = '';
 
-    $pos = 0;
-    $bytes = strlen($data);
-    while ($bytes) {
-      $accum = 0;
-      for ($count = 24; $count >= 0; $count -= 8) {
-        $val = ord($data[$pos++]);
-        $val = $val * (1 << $count);
-        $accum = $accum + $val;
-        if (--$bytes == 0) {
-          break;
-        }
+    $lines = str_split($input, 52);
+    $final = (count($lines) - 1);
+
+    foreach ($lines as $idx => $line) {
+      if ($idx === $final) {
+        $len = strlen($line);
+      } else {
+        $len = 52;
       }
-      $slice = '';
-      for ($count = 4; $count >= 0; $count--) {
-        $val = (int)fmod($accum, 85.0);
-        $accum = floor($accum / 85.0);
-        $slice .= $map[$val];
+
+      // The first character encodes the line length.
+      $buf .= $len_map[$len];
+
+      $pos = 0;
+      while ($len) {
+        $accum = 0;
+        for ($count = 24; $count >= 0; $count -= 8) {
+          $val = ord($line[$pos++]);
+          $val = $val * (1 << $count);
+          $accum = $accum + $val;
+          if (--$len == 0) {
+            break;
+          }
+        }
+
+        $slice = '';
+
+        // If we're in 64bit mode, we can just use integers. Otherwise, we
+        // need to use floating point math to avoid overflows.
+
+        if ($is_64bit) {
+          for ($count = 4; $count >= 0; $count--) {
+            $val = $accum % 85;
+            $accum = $accum / 85;
+            $slice .= $map[$val];
+          }
+        } else {
+          for ($count = 4; $count >= 0; $count--) {
+            $val = (int)fmod($accum, 85.0);
+            $accum = floor($accum / 85.0);
+            $slice .= $map[$val];
+          }
+        }
+
+        $buf .= strrev($slice);
       }
-      $buf .= strrev($slice);
+
+      $buf .= $eol;
     }
 
     return $buf;
   }
 
 }
diff --git a/src/parser/__tests__/ArcanistBundleTestCase.php b/src/parser/__tests__/ArcanistBundleTestCase.php
index 94b3517f..f64e8992 100644
--- a/src/parser/__tests__/ArcanistBundleTestCase.php
+++ b/src/parser/__tests__/ArcanistBundleTestCase.php
@@ -1,958 +1,970 @@
 <?php
 
 final class ArcanistBundleTestCase extends PhutilTestCase {
 
   private function loadResource($name) {
     return Filesystem::readFile($this->getResourcePath($name));
   }
 
   private function getResourcePath($name) {
     return dirname(__FILE__).'/bundle/'.$name;
   }
 
   private function loadDiff($old, $new) {
     list($err, $stdout) = exec_manual(
       'diff --unified=65535 --label %s --label %s -- %s %s',
       'file 9999-99-99',
       'file 9999-99-99',
       $this->getResourcePath($old),
       $this->getResourcePath($new));
     $this->assertEqual(
       1,
       $err,
       pht(
         "Expect `%s` to find changes between '%s' and '%s'.",
         'diff',
         $old,
         $new));
     return $stdout;
   }
 
   private function loadOneChangeBundle($old, $new) {
     $diff = $this->loadDiff($old, $new);
     return ArcanistBundle::newFromDiff($diff);
   }
 
   public function testTabEncoding() {
     // See T8768. Test that we add semantic trailing tab literals to diffs
     // touching files with spaces in them. This is a pain to encode using the
     // support toolset here so just do it manually.
 
     // Note that the "b/X Y.txt" line has a trailing tab literal.
 
     $diff = <<<EODIFF
 diff --git a/X Y.txt b/X Y.txt
 new file mode 100644
 --- /dev/null
 +++ b/X Y.txt\t
 @@ -0,0 +1 @@
 +quack
 
 
 EODIFF;
 
     $bundle = ArcanistBundle::newFromDiff($diff);
 
     $changes = $bundle->getChanges();
     $this->assertEqual(1, count($changes));
 
     // The path should parse as "X Y.txt" despite the trailing tab.
     $change = head($changes);
     $this->assertEqual('X Y.txt', $change->getCurrentPath());
 
     // The tab should be restored when the diff is output again.
     $this->assertEqual($diff, $bundle->toGitPatch());
   }
 
   /**
    * Unarchive a saved git repository and apply each commit as though via
    * "arc patch", verifying that the resulting tree hash is identical to the
    * tree hash produced by the real commit.
    */
   public function testGitRepository() {
     if (phutil_is_windows()) {
       $this->assertSkipped(pht('This test is not supported under Windows.'));
     }
 
     $archive = dirname(__FILE__).'/bundle.git.tgz';
     $fixture = PhutilDirectoryFixture::newFromArchive($archive);
 
     $old_dir = getcwd();
     chdir($fixture->getPath());
 
     $caught = null;
     try {
       $this->runGitRepositoryTests($fixture);
     } catch (Exception $ex) {
       $caught = $ex;
     }
 
     chdir($old_dir);
 
     if ($caught) {
       throw $ex;
     }
   }
 
   private function runGitRepositoryTests(PhutilDirectoryFixture $fixture) {
     $patches = dirname(__FILE__).'/patches/';
 
     list($commits) = execx(
       'git log --format=%s',
       '%H %T %s');
     $commits = explode("\n", trim($commits));
 
     // The very first commit doesn't have a meaningful parent, so don't examine
     // it.
     array_pop($commits);
 
     foreach ($commits as $commit) {
       list($commit_hash, $tree_hash, $subject) = explode(' ', $commit, 3);
       execx('git reset --hard %s --', $commit_hash);
 
       $fixture_path = $fixture->getPath();
       $working_copy = ArcanistWorkingCopyIdentity::newFromPath($fixture_path);
 
       $configuration_manager = new ArcanistConfigurationManager();
       $configuration_manager->setWorkingCopyIdentity($working_copy);
       $repository_api = ArcanistRepositoryAPI::newAPIFromConfigurationManager(
         $configuration_manager);
 
       $repository_api->setBaseCommitArgumentRules('arc:this');
       $diff = $repository_api->getFullGitDiff(
         $repository_api->getBaseCommit(),
         $repository_api->getHeadCommit());
 
       $parser = new ArcanistDiffParser();
       $parser->setRepositoryAPI($repository_api);
       $changes = $parser->parseDiff($diff);
 
       $this->makeChangeAssertions($commit_hash, $changes);
 
       $bundle = ArcanistBundle::newFromChanges($changes);
 
       execx('git reset --hard %s^ --', $commit_hash);
 
       $patch = $bundle->toGitPatch();
 
       $expect_path = $patches.'/'.$commit_hash.'.gitpatch';
       $expect = null;
       if (Filesystem::pathExists($expect_path)) {
         $expect = Filesystem::readFile($expect_path);
       }
 
       if ($patch === $expect) {
         $this->assertEqual($expect, $patch);
       } else {
         Filesystem::writeFile($expect_path.'.real', $patch);
         throw new Exception(
           pht(
             "Expected patch and actual patch for %s differ. ".
             "Wrote actual patch to '%s.real'.",
             $commit_hash,
             $expect_path));
       }
 
       try {
         id(new ExecFuture('git apply --index --reject'))
           ->write($patch)
           ->resolvex();
       } catch (CommandException $ex) {
         $temp = new TempFile(substr($commit_hash, 0, 8).'.patch');
         $temp->setPreserveFile(true);
         Filesystem::writeFile($temp, $patch);
 
         PhutilConsole::getConsole()->writeErr(
           "%s\n",
           pht("Wrote failing patch to '%s'.", $temp));
         throw $ex;
       }
 
       // If these aren't configured, Git complains even if we pass --author.
       $git_name = 'unit-test';
       $git_email = 'unit-test@phabricator.com';
 
       execx(
         'git -c user.name=%s -c user.email=%s commit -m %s',
         $git_name,
         $git_email,
         $subject);
       list($result_hash) = execx('git log -n1 --format=%s', '%T');
       $result_hash = trim($result_hash);
 
       $this->assertEqual(
         $tree_hash,
         $result_hash,
         pht('Commit %s: %s', $commit_hash, $subject));
     }
   }
 
   private function makeChangeAssertions($commit, array $raw_changes) {
     $changes = array();
 
     // Verify that there are no duplicate changes, and rekey the changes on
     // affected path because we don't care about the order in which the
     // changes appear.
     foreach ($raw_changes as $change) {
       $this->assertTrue(
         empty($changes[$change->getCurrentPath()]),
         'Unique Path: '.$change->getCurrentPath());
       $changes[$change->getCurrentPath()] = $change;
     }
 
     switch ($commit) {
       case '1830a13adf764b55743f7edc6066451898d8ffa4':
         // "Mark koan2 as +x and edit it."
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_CHANGE,
           $c->getType());
 
         $this->assertEqual(
           '100644',
           idx($c->getOldProperties(), 'unix:filemode'));
 
         $this->assertEqual(
           '100755',
           idx($c->getNewProperties(), 'unix:filemode'));
         break;
       case '8ecc728bcc9b482a9a91527ea471b04fc1a025cf':
         // "Move 'text' to 'executable' and mark it +x."
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['executable'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
 
         $this->assertEqual(
           '100644',
           idx($c->getOldProperties(), 'unix:filemode'));
 
         $this->assertEqual(
           '100755',
           idx($c->getNewProperties(), 'unix:filemode'));
         break;
       case '39c8e7dd3914edff087a6214f0cd996ad08e5b3d':
         // "Mark koan as +x."
         // Primarily a test against a recusive synthetic hunk construction bug.
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_CHANGE,
           $c->getType());
 
         $this->assertEqual(
           '100644',
           idx($c->getOldProperties(), 'unix:filemode'));
 
         $this->assertEqual(
           '100755',
           idx($c->getNewProperties(), 'unix:filemode'));
         break;
       case 'c573c25d1a767d270fed504cd993e78aba936338':
         // "Copy a koan over text, editing the original koan."
         // Git doesn't really do anything meaningful with this.
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_CHANGE,
           $c->getType());
 
         $c = $changes['text'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_CHANGE,
           $c->getType());
 
         break;
       case 'd26628e588cf7d16368845b121c6ac6c781e81d0':
         // "Copy a koan, modifying both the source and destination."
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_AWAY,
           $c->getType());
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_HERE,
           $c->getType());
 
         break;
       case 'b0c9663ecda5f666f62dad245a3a7549aac5e636':
         // "Remove a koan copy."
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_DELETE,
           $c->getType());
 
         break;
       case 'b6ecdb3b4801f3028d88ba49940a558360847dbf':
         // "Copy a koan and edit the destination."
         // Git does not detect this as a copy without --find-copies-harder.
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_ADD,
           $c->getType());
 
         break;
       case '30d23787e1ecd254c884afbe37afa612f61e3904':
         // "Move and edit a koan."
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_AWAY,
           $c->getType());
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
 
         break;
       case 'c0ba9bfe3695f95c3f558bc5797eeba421d32483':
         // "Remove two koans."
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['koan3'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_DELETE,
           $c->getType());
 
         $c = $changes['koan4'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_DELETE,
           $c->getType());
 
         break;
       case '2658fd01d5355abe5d4c7ead3a0e7b4b3449fe77':
         // "Multicopy a koan."
 
         $this->assertEqual(3, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MULTICOPY,
           $c->getType());
 
         $c = $changes['koan3'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_HERE,
           $c->getType());
 
         $c = $changes['koan4'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
 
         break;
       case '1c5fe4e2243bb19d6b3bf15896177b13768e6eb6':
         // "Copy a koan."
         // Git does not detect this as a copy without --find-copies-harder.
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_ADD,
           $c->getType());
 
         break;
       case '6d9eb65a2c2b56dee64d72f59554c1cca748dd34':
         // "Move a koan."
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_AWAY,
           $c->getType());
 
         $c = $changes['koan2'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
 
         break;
       case '141452e2a775ee86409e8779dd2eda767b4fe8ab':
         // "Add a koan."
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['koan'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_ADD,
           $c->getType());
 
         break;
       case '5dec8bf28557f078d1987c4e8cfb53d08310f522':
         // "Copy an image, and replace the original."
         // `image_2.png` is copied to `image.png` and then replaced.
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['image.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_HERE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         $c = $changes['image_2.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_AWAY,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getOriginalFileData()));
         $this->assertEqual(
           'c9ec1b952480da09b393ba672d9b13da',
           md5($c->getCurrentFileData()));
 
         break;
       case 'fb28468d25a5fdd063aca4ca559454c998a0af51':
         // "Multicopy image."
         // `image.png` is copied to `image_2.png` and `image_3.png` and then
         // deleted. Git detects this as a move and an add.
 
         $this->assertEqual(3, count($changes));
 
         $c = $changes['image.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MULTICOPY,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getOriginalFileData()));
         $this->assertEqual(
           null,
           $c->getCurrentFileData());
 
         $c = $changes['image_2.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_COPY_HERE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         $c = $changes['image_3.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         break;
       case 'df340e88d8aba12e8f2b8827f01f0cd9f35eb758':
         // "Remove binary image."
         // `image_2.png` is deleted.
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['image_2.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_DELETE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getOriginalFileData()));
         $this->assertEqual(
           null,
           $c->getCurrentFileData());
 
         break;
       case '3f5c6d735e64c25a04f83be48ef184b25b5282f0':
         // "Copy binary image."
         // `image_2.png` is copied to `image.png`. Git does not detect this as
         // a copy without --find-copies-harder.
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['image.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_ADD,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         break;
       case 'b454edb3bb29890ee5b3af5ef66ce6a24d15d882':
         // "Move binary image."
         // `image.png` is moved to `image_2.png`.
 
         $this->assertEqual(2, count($changes));
 
         $c = $changes['image.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_AWAY,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getOriginalFileData()));
         $this->assertEqual(
           null,
           $c->getCurrentFileData());
 
         $c = $changes['image_2.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_MOVE_HERE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         break;
       case '5de5f3dfda1b7db2eb054e57699f05aaf1f4483e':
         // "Add a binary image."
         // `image.png` is added.
 
         $c = $changes['image.png'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_ADD,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_BINARY,
           $c->getFileType());
         $this->assertEqual(
           null,
           $c->getOriginalFileData());
         $this->assertEqual(
           '8645053452b2cc2f955ef3944ac0831a',
           md5($c->getCurrentFileData()));
 
         break;
       case '176a4c2c3fd88b2d598ce41a55d9c3958be9fd2d':
         // "Convert \r\n newlines to \n newlines."
       case 'a73b28e139296d23ade768f2346038318b331f94':
         // "Add text with \r\n newlines."
       case '337ccec314075a2bdb4a912ef467d35d04a713e4':
         // "Convert \n newlines to \r\n newlines.";
       case '6d5e64a4a7a6a036c53b1d087184cb2c70099f2c':
         // "Remove tabs."
       case '49395994a1a8a06287e40a3b318be4349e8e0288':
         // "Add tabs."
       case 'a5a53c424f3c2a7e85f6aee35e834c8ec5b3dbe3':
         // "Add trailing newline."
       case 'd53dc614090c6c7d6d023e170877d7f611f18f5a':
         // "Remove trailing newline."
       case 'f19fb9fa1385c01b53bdb6d8842dd154e47151ec':
         // "Edit a text file."
 
         $this->assertEqual(1, count($changes));
 
         $c = $changes['text'];
         $this->assertEqual(
           ArcanistDiffChangeType::TYPE_CHANGE,
           $c->getType());
         $this->assertEqual(
           ArcanistDiffChangeType::FILE_TEXT,
           $c->getFileType());
         break;
       case '228d7be4840313ed805c25c15bba0f7b188af3e6':
         // "Add a text file."
         // This commit is never reached because we skip the 0th commit junk.
         $this->assertTrue(true, pht('This is never reached.'));
         break;
       default:
         throw new Exception(
           pht('Commit %s has no change assertions!', $commit));
     }
   }
 
   public function testTrailingContext() {
     // Diffs need to generate without extra trailing context, or 'patch' will
     // choke on them.
     $this->assertEqual(
       $this->loadResource('trailing-context.diff'),
       $this->loadOneChangeBundle(
         'trailing-context.old',
         'trailing-context.new')->toUnifiedDiff());
   }
 
   public function testDisjointHunks() {
     // Diffs need to generate without overlapping hunks.
     $this->assertEqual(
       $this->loadResource('disjoint-hunks.diff'),
       $this->loadOneChangeBundle(
         'disjoint-hunks.old',
         'disjoint-hunks.new')->toUnifiedDiff());
   }
 
   public function testNonlocalTrailingNewline() {
     // Diffs without changes near the end of the file should not generate a
     // bogus, change-free hunk if the file has no trailing newline.
     $this->assertEqual(
       $this->loadResource('trailing-newline.diff'),
       $this->loadOneChangeBundle(
         'trailing-newline.old',
         'trailing-newline.new')->toUnifiedDiff());
   }
 
   public function testEncodeBase85() {
 
     $data = '';
     for ($ii = 0; $ii <= 255; $ii++) {
       $data .= chr($ii);
     }
     for ($ii = 255; $ii >= 0; $ii--) {
       $data .= chr($ii);
     }
 
     $expect = Filesystem::readFile(dirname(__FILE__).'/base85/expect1.txt');
-    $expect = trim($expect);
-
-    $this->assertEqual(
-      $expect,
-      ArcanistBundle::encodeBase85($data));
+    $this->assertBase85($expect, $data, pht('Byte Sequences'));
 
     // This is just a large block of random binary data, it has no special
     // significance.
 
     $data =
       "\x56\x4c\xb3\x63\xe5\x4a\x9f\x03\xa3\x4c\xdd\x5d\x85\x86\x10".
       "\x30\x3f\xc1\x28\x51\xd8\xb2\x1a\xc3\x79\x15\x85\x31\x66\xf9".
       "\x8e\xe1\x20\x8f\x12\xa1\x94\x0e\xbf\xb6\x9c\xb5\xc0\x15\x43".
       "\x3d\xad\xed\x00\x3c\x16\xfa\x76\x2f\xed\x99\x3a\x78\x3e\xd1".
       "\x91\xf8\xb0\xca\xb9\x29\xfe\xd4\x0f\x16\x70\x19\xad\xd9\x42".
       "\x15\xb4\x8f\xd6\x8f\x80\x62\xe9\x48\x77\x9f\x38\x6d\x3f\xd6".
       "\x0e\x40\x68\x68\x93\xae\x75\x6d\x7f\x75\x9c\x80\x69\x94\x22".
       "\x87\xb6\xc0\x62\x6b\xab\x49\xb8\x91\xe9\x96\xbf\x04\xc2\x50".
       "\x30\xae\xea\xc1\x70\x8e\x91\xd0\xb6\xec\x56\x14\x78\xd5\x8a".
       "\x8c\x52\xd1\x3c\xde\x65\x21\xec\x93\xab\xcf\x7e\xf5\xfd\x6d".
       "\x2d\x69\xb9\x2e\xa3\x42\x7b\x4d\xa5\xfb\x28\x6d\x74\xa3\x7b".
       "\x3a\xc5\x34\x7c\x63\xa9\xf9\x8e\x34\x14\x42\xb0\xf1\x0e\xe2".
       "\xd0\xd2\x04\x81\xff\x62\xd5\xd9\x46\x3b\x36\x88\x8a\x93\x55".
       "\x02\x2c\xff\x9f\x48\xd6\x7a\xcb\xbf\x6a\x33\xaa\x6b\x08\x4c".
       "\x96\x98\x89\x53\x56\xb4\xb3\x9b\x06\xb1\xa0\x13\x69\xfa\x6a".
       "\xa8\x0d\x6a\xda\xb2\x6f\x62\x0b\xa8\xf6\x59\x29\x46\x7d\x04".
       "\x44\xeb\x90\x6f\xd7\xc7\xb6\xca\xc5\xeb\xde\x10\x9b\xbd\xf2".
       "\x66\x8e\xd0\x0b\xda\x8c\xeb\x90\x73\x73\x33\xe7\x6f\x26\x57".
       "\x4e\xfc\x95\xe0\xfc\x62\x93\xa7\x28\xe6\x0c\x46\x73\xdd\x01".
       "\xce\x43\x9b\x4e\x16\x74\x5b\x36\x92\x5a\x66\x4c\xe3\x9e\x90".
       "\x2d\x9a\x1a\x3d\x69\x39\x67\x04\xd6\xf8\x5f\x45\xee\xbb\xd4".
       "\x63\xcf\x8c\x9b\x31\x69\x98\x1a\x98\x57\x4b\xa9\x49\xf6\x1b".
       "\x76\x28\xd7\xe3\x8f\x63\x95\x5b\x06\xe2\xa8\x66\x60\xf9\x49".
       "\x4e\x40\x53\x32\x9b\x74\x36\xc0\x56\xf4\x33\xec\x83\xd2\x2c".
       "\x69\x60\x55\x11\x3b\x4f\xd6\x0a\xf6\x04\x38\x75\xb6\xc2\x82".
       "\x4d\xfa\x83\x56\xba\x35\x42\xc3\xcb\xdc\x28\xf4\x69\x48\xa9".
       "\xe0\x51\x41\x79\x66\xfe\x61\xd1\xf2\x9f\x7b\xde\xc4\x3e\x8f".
       "\x8f\xb6\x9c\x0a\x74\xf8\x71\x03\x37\x37\x30\x8d\x2a\x6a\xc9".
       "\x51\xa1\xe2\x34\xe5\x42\xdb\x4f\x61\x4e\x16\xfc\x23\x72\x12".
       "\x46\x53\x12\x82\x3e\x44\x63\x23\x82\xaa\xab\x7e\x8d\x70\x66".
       "\xf1\x94\x86\x02\xc5\x3e\x9c\x79\x17\x1e\x9f\x13\x89\x3d\x25".
       "\x45\xc9\x3b\x1e\xa0\x1a\x03\x20\x1c\x81\x6b\xfc\xb5\xc9\xe2".
       "\xda\xb1\x87\x34\xa0\xb2\x72\x36\x68\x12\x05\x53\x7c\x68\x6b".
       "\x1e\x2a\x56\x2a\x7e\x7f\xd0\x9c\x13\xa9\xb2\x4c\xe6\x8a\x65".
       "\xd7\x67\xad\xf3\xf3\x2b\x9c\xe8\x10\x07\x8a\xe2\x20\x67\xe4".
       "\x51\x47\xc1\x22\x91\x05\x22\x39\x1a\xef\x54\xd2\x8a\x88\x55".
       "\x3f\x83\xba\x73\xd4\x95\xc7\xb8\xa2\xfd\x4d\x4e\x5d\xff\xdd".
       "\xaf\x1a\xc2\x7e\xb5\xfa\x86\x5f\x93\x38\x5d\xca\x9a\x5a\x7e".
       "\xb7\x47\xd5\x5c\x6b\xf3\x32\x03\x11\x44\xe9\x49\x12\x40\x82".
       "\x67\x7d\x2a\x5a\x61\x81\xbd\x24\xaa\xd7\x7c\xc9\xcf\xaf\xb0".
       "\x3e\xb0\x43\xcd\xce\x21\xe4\x1b\x5a\xd6\x40\xf5\x0e\x23\xef".
       "\x70\xf4\xc6\xd2\xd7\x36\xd7\x20\xda\x8d\x39\x46\xea\xfc\x78".
       "\x55\xa2\x02\xd6\x77\x21\xc8\x97\x1e\xdf\x45\xde\x93\xa7\x74".
       "\xd8\x59\x10\x24\x8a\xe8\xcd\xe9\x00\xb5\x4e\xe6\x49\xb0\xde".
       "\x14\x1a\x5d\xdd\x38\x47\xb0\xc7\x1e\xec\x7c\x76\xc9\x21\x3c".
       "\x3a\x85\x4f\x71\x97\xed\x4a\x94\x2c\x51\x48\x9c\x43\x90\x70".
       "\xe9\x0e\x84\x55\xd2\xa4\x48\xfa\xfd\x54\x12\x11\xb9\x32\xfc".
       "\x1d\x66\xe7\x42\xe3\x5e\x65\xf4\x3d\xea\x1a\x53\xe3\x7b\x4b".
       "\xee\xdb\x74\xce\x30\xd3\x04\xcb\xda\xa4\xdd\xad\x98\x3a\x76".
       "\xe8\xba\x1b\x03\x53\xed\x46\x5d\xef\xd4\x34\xc2\x8d\xef\xae".
       "\x51\x35\x0f\x4d\x40\xaa\x3a\xdb\x50\x1a\xbe\x5f\x8b\xb8\x24".
       "\x40\x19\x8f\x8a\x6b\x44\x4f\x9b\xe0\xf4\x9c\x4b\xc4\x23\x37".
       "\xf0\xb3\xe1\x58\x9d\x0e\xd9\xa9\xf7\x3e\x86\x43\x9b\x5b\x90".
       "\x3c\xc0\x20\xa0\xc5\x86\x4f\xc6\xcb\xb5\xcb\xd4\x88\xc6\x72".
       "\x57\xa7\x57\x2c\x34\x26\x91\x44\x15\xa8\xf4\x88\xca\x74\x56".
       "\x9e\x12\x6c\xdf\x52\xef\xc0\xb4\x5c\x16\xe8\xaa\xf7\xb6\xf3".
       "\x7c\xda\xcd\x42\xf9\x1c\x40\x88\x44\x68\x4f\x1b\x5a\x7b\x8f".
       "\xc3\x47\x48\xd3\xf3\xe5\xf5\x66\x35\x48\xbe\x64\xdf\xfe\x35".
       "\xf1\xc3\xe4\xa8\xfc\x86\xfb\x69\x20\xc9\xf4\x16\x96\xc1\x7a".
       "\x51\x14\x77\xa4\x6e\x13\xe8\x59\x35\x24\xf1\xe5\xfe\xe9\x98".
       "\x0d\xd1\xe8\xce\x9c\x7f\xf8\x3b\x79\x39\x3a\x1d\xa3\x77\xef".
       "\x4f\x4b\x59\x73\x03\xb3\xfe\xae\x70\x2a\x3a\xf0\x79\x9d\x7e".
       "\x9b\xaa\xb1\x18\xf9\x43\x69\xf3\x55\x46\xad\x38\xa2\xf1\xcb".
       "\xce\x37\xa9\x88\x20\x38\xea\x19\x29\x95\x8c\x75\x06\x9d\x1d".
       "\x9e\xf2\xb7\x64\x98\x21\x36\x90\x92\xf8\xb8\x89\x1e\x5c\x5d".
       "\x09\x3b\x52\xc5\x6a\x87\x7e\x46\xca\x8c\xdf\xe7\xca\xa9\x7b".
       "\x11\x63\x0f\x9e\x42\x9a\x3e\xe0\x8b\x80\x9e\x91\x76\x88\x9a".
       "\xa1\xe2\x96\xae\xfb\x18\x39\xdc\x92\x99\x34\xfd\x98\x20\xa8".
       "\x89\x61\x2c\x26\xe0\xb8\x83\xa7\xe7\x50\x42\x8f\xfc\x36\x66".
       "\x6b\x25\xc5\x6d\xb4\x31\xe1\x4d\x0f\x2e\xf8\x44\xe2\xb6\x6a".
       "\x6d\xfe\x83\x9e\x2c\x07\x2f\x15\x41\xf3\xe7\xa6\x18\x2b\x84".
       "\x7e\xeb\x43\xcc\xbb\xdb\xa9\x54\x5c\xbc\x59\x6a\xdc\x26\x2a".
       "\xf4\x59\xa7\x75\xa4\xac\xed\x73\x8f\x16\x43\x0d\x97\x10\x2c".
       "\x70\xef\x9e\xb2\xc9\xdf\xe6\xa7\x9b\x08\x79\xa3\xf7\x99\xf5".
       "\x59\xe4\xd5\x89\x10\xe5\xc9\xf7\xe7\x29\x72\x06\xc6\x54\xc3".
       "\xcd\xd0\xff\x69\xf8\xdf\x19\xf2\x66\x1c\x69\x40\xbc\x97\xf1".
       "\x49\x5e\x78\x62\x52\x46\x7f\xcf\x44\x50\x8b\x5f\xe7\xa8\xeb".
       "\xd5\x84\x24\x81\xc0\x2c\x65\xf7\x95\xbd\xf2\x8e\x43\xfb\x6a".
       "\x49\x3c\x6a\xe5\x2a\x39\xf0\xfa\x89\x59\x5f\x39\x75\xb4\x6f".
       "\x04\xf1\xe0\x2c\xcd\x77\x34\xec\x6b\x45\x16\xe3\x18\x24\x05".
       "\xb9\x68\xc1\x4e\x71\x4b\xff\x88\x18\xea\x0d\x56\x49\x55\xdf".
       "\xe5\xb0\x59\xdb\x74\x9e\x0b\x38\x03\x9f\x10\x6f\xd9\x34\x07".
       "\x44\x29\x08\xb1\xd4\x77\xc6\x84\x0d\xbb\xb5\xd5\x09\x05\x19".
       "\x01\x62\x29\x45\x52\x1d\xc6\x4f\x25\x78\x7e\xbc\xae\x07\xb3".
       "\xd4\xe0\x19\x91\x03\xd6\x8d\x2f\x00\xc9\xb2\x66\x3b\x4e\x3d".
       "\x75\xf7\x23\x9a\x3e\xa4\xd5\x7f\x75\x47\xd0\xbc\xc3\xc8\x2a".
       "\xdc\x85\x09\x6c\x0c\x90\x38\xd8\xef\xcf\xf4\x7a\x1b\xc7\x76".
       "\xe0\xdb\x81\xa8\x1b\x2b\x8d\xd4\x36\x90\x76\xde\x8a\x90\xc8".
       "\x5b\x05\x00\xeb\xb3\x20\xce\x6e\x5c\xb9\x35\x3d\x95\x3a\x79".
       "\x4a\x60\xeb\x23\x11\xfb\x90\x2d\xf6\xb7\x05\x4a\x43\x41\x79".
       "\x51\xaa\xe6\x90\x0a\x71\x87\x80\xbe\xb0\x89\x0f\xd3\x84\x19".
       "\xce\x6c\xf9\xbb\x1b\x15\x4d\x0f\x33\x65\xf7\x9e\x3a\xd9\x8c".
       "\x02\x43\xcf\xdf\xb2\x60\xc1\x4c\xe9\xa5\x3c\xaf\xfa\x41\x2d".
       "\xb9\x1f\x45\x32\xcb\x39\x2f\x94\xae\x44\x6d\x69\xc1\xc9\x57".
       "\x8c\xe5\xf4\xa4\x3a\xb6\x70\x61\xf9\xbb\x41\xdc\x78\xf0\xf7".
       "\xbf\xa8\x8e\xe3\x77\x51\xce\x25\x2f\xdf\x27\x6b\x07\x30\x9f".
       "\xce\xdb\x59\x58\xaa\xb2\x2e\xdc\x90\x92\x82\x55\xfe\x25\x36".
       "\x49\x7f\x6d\x2d\x39\x51\xef\x3d\xc8\xa3\x87\x0b\xe7\xf2\xac".
       "\x90\xa0\x1d\xd8\xc7\xea\x93\x53\x3b\x21\x84\x2e\x52\x6c\xfb".
       "\x4f\x31\xda\xd1\xea\x45\x3e\xdc\xeb\x52\x81\x8c\x2b\xf4\x2a".
       "\xbc\x01\xc4\xe7\x68\x36\x9c\xd5\x2d\xc1\x61\xcb\x9a\x5f\x18".
       "\x00\x6a\xc8\x9a\x4e\xfd\x31\x5b\xce\x90\x4e\x45\xff\x7f\xea".
       "\xb2\x26\xad\xc1\x3a\x21\xa9\xe8\x7c\x14\xae\x81\x1e\xbe\xa3".
       "\x6d\xda\x92\x1b\xeb\xf2\x69\x76\x3e\xf1\x2b\xf7\x1a\x45\xd5".
       "\xb3\x81\xb1\xbe\x80\x7f\x24\xba\x0e\xd5\x68\x34\x3f\x1a\x29".
       "\x15\x0e\xc2\x26\x62\x0c\xaa\xa9\x20\x4c\x61\x65\x49\x07\xbe".
       "\x69\xf4\xc9\xec\x2f\x1c\xfa\x59\x2e\x72\xc0\x17\xc5\x4c\xfa".
       "\xba\x2f\x64\xab\xa9\xb4\xcb\xdc\xcb\x25\x5f\xcf\x0c\x87\xcc".
       "\xf0\x36\x2b\xce\x81\x5a\x22\x85\xa0\x50\x50\x97\x8e\xda\x36".
       "\x80\x74\xb5\x1e\x02\x3f\xd7\xc8\x29\x11\xeb\x1d\x3d\x74\x9f".
       "\x26\x1a\xa4\x3d\xf9\x0e\xf0\x2d\x5c\xa9\x43\xbf\x51\x6c\x8d".
       "\xe6\x78\xe0\x67\x57\xf0\xc8\x0e\x97\x9c\x57\x23\x30\xac\x63".
       "\xdf\x46\x98\xa4\xaf\x4e\xa7\xe5\xac\x31\xbd\xeb\x6a\xa0\xb0".
       "\xe4\x94\x7e\x51\xf6\x89\x81\x3e\xab\x4f\x64\xb7\xc5\x51\x71".
       "\xcd\x74\x02\xa9\x02\x99\x5c\xab\x0e\x14\x47\x3b\x04\xc1\x9b".
       "\x59\x1a\x93\x92\x4c\x71\x20\x5f\x6e\xd3\xf3\xa7\x47\x1b\x39".
       "\x3e\x73\x69\xe2\xec\xcb\x52\xb3\x5c\x7a\x95\x25\x3f\x16\x98".
       "\x60\xa8\xa2\x5d\xc4\x5a\x67\xe4\x11\x06\x06\xf9\x7a\xb4\x14".
       "\xe0\xbc\x7b\x13\x1d\x0f\xf2\xca\x0b\xd4\xaa\x71\x35\x3e\xd6".
       "\x2e\x2e\x5d\x7b\x15\xc9\x23\x1a\xa9\x24\x31\x48\xd4\xcf\x4a".
       "\xf4\x32\x17\x9b\x1d\x4b\xfe\x49\x69\xd6\xc0\x8f\xb9\xdb\x72".
       "\x52\x2c\xe8\xf3\xc4\xfc\x46\xf5\xb8\x1b\x05\x06\xcf\xcc\x23".
       "\x34\xbf\x25\x6a\xea\x3c\xc7\x64\xd4\xd5\xb3\x67\xed\x24\x27".
       "\xd3\x67\xc1\xbd\x9f\x7b\x7d\x19\x04\x5c\xd1\x96\x7e\xa5\xc7".
       "\xbb\xb2\x84\x68\x98\x38\x11\x90\xfb\x62\x15\xfd\xe6\xb7\x24".
       "\x77\xb2\x78\xc7\x73\x91\xc9\x60\x1d\x91\x6d\x04\x2b\x41\xe9".
       "\xc9\xfa\xe4\x98\x54\x83\x9a\x6e\x76\x8c\x21\xf9\x91\x38\x1f".
       "\xdc\xfe\x13\x09\x30\xd7\x53\x63\x62\xba\xe3\x2c\x70\xd5\xfc".
       "\x78\x35\x36\x79\x5d\xb6\x0e\x35\x3d\x46\x87\xfb\xf5\x64\x1f".
       "\x3e\xfd\x2f\x1c\xbb\xed\x95\x2d\xd6\x63\xdc\xa7\x6a\x39\x8f".
       "\xbd\xcb\x79\x95\xe9\x45\xbf\xe4\x3e\x05\x55\x00\xdb\x33\x28".
       "\x3a\x6c\xe2\x35\xbb\xac\x70\x52\x2b\xac\x4e\x11\x44\x58\x16".
       "\x21\xb4\xae\x0d\x6a\xb9\xdc\x85\x5d\x90\x11\x26\x85\xdb\xc3".
       "\xf0\x38\x6f\x8a\xff\x12\xf0\xc9\x9e\xf0\xfc\xae\x94\x11\x4d".
       "\xce\x96\x29\x09\x6c\xf4\x2a\x6c\xda\x1e\x4c\x4a\xa2\x96\x5a".
       "\xef\xc6\x38\x5c\x60\xa2\x28\x13\x58\x73\x96\xde\x59\x2a\x57".
       "\x64\x6c\x14\x94\x8a\x2e\x8e\x21\x3f\xa2\x43\xde\xf6\x2d\x23".
       "\x74\x5c\xbd\x7a\x10\xdb\x17\xa8\x93\xd0\x74\x86\x9d\x33\x07".
       "\x48\xee\xac\x18\x6d\x64\x61\x7b\x61\x2b\xa4\xa2\xab\x99\x59".
       "\xbe\x19\xd7\x19\x41\x1e\x61\x87\xad\x40\x5b\x69\x8c\x32\xf5".
       "\xb6\x49\xbe\x1f\xad\xd8\x0f\x3e\xd9\x62\xac\x3a\x76\xde\x32".
       "\xa3\xb2\x41\x95\xad\x17\x23\xab\xa1\x37\x9c\xab\x73\x79\x70".
       "\xd6\x66\x0d\x6e\x4d\x8b\xa0\xac\xe3\x44\x1e\x0a\xee\xf0\x74".
       "\x64\xd8\x44\xd1\x6c\xa6\xd5\x36\x2e\xd9\x55\x6e\x90\x63\xb7".
       "\xf7\x8e\xc6\x28\xa3\x40\x00\x60\x9a\x3c\xfe\xff\x03\x30\x11".
       "\x18\x92\x2f\x5b\x23\xe1\x4e\x99\xe4\x82\xc9\x51\xe2\x15\x6a".
       "\x76\x5c\x67\xae\xa3\xa2\x9c\x85\x51\xe0\x44\x89\x63\xa5\x71".
       "\x99\xbc\x2d\x9c\xab\x9a\xfb\x20\x37\x58\xd6\x2d\x8b\x7d\x42".
       "\x13\x35\x44\x4c\x11\x97\x66\x27\x17\xac\x44\xe8\x6a\x03\x78".
       "\xa2\x88\xc6\x36\x71\x5a\x5a\x5a\x72\xa3\xe9\x72\x0c\x91\x31".
       "\xfc\xae\x7b\xa0\x75\x21\x0a\xc1\x4b\x95\xcb\xe3\xc2\xee\x03".
       "\x0f\xb8\xb2\x51\xc7\xc8\x9c\x8d\x6d\x3a\xe7\x4e\x2c\xaa\xeb".
       "\x5e\x49\x93\xe0\x8f\xa1\x54\x93\xe7\x7c\x5d\x31\xc7\x05\x00".
       "\x28\x14\x57\x47\xb3\x05\x2d\x17\x92\x28\x45\xee\x85\x3a\x59".
       "\xb6\xa6\x04\xc0\x5c\x07\x1f\xe6\x5b\x36\x53\x62\x82\x64\xd5".
       "\xb6\xf2\xf5\x67\x19\x11\xee\xd2\x70\xc5\x14\x63\xc1\x75\xe1".
       "\x24\xe5\x01\x59\x52\x7c\x88\x17\xb4\xe0\x15\xe9\x12\x05\xcd".
       "\x88\x7a\xd5\xea\x45\xc3\xbb\x65\xd4\xdd\x0d\xde\x36\x94\x98".
       "\x0d\x2c\xfb\x3c\x2f\x69\xd0\x28\xe2\x85\xd9\x27\xf3\x7a\xad".
       "\x50\x68\x96\x54\x5e\xeb\xbc\x2a\x74\xde\xf3\x4e\x8b\x27\x0a".
       "\xcf\x4c\x60\x40\xe8\xc5\x72\xab\x8c\xfd\xe9\xab\xff\x51\xe5".
       "\xd6\xea\x9e\x34\x73\xe1\xe6\xf8\x5b\xb1\x10\xf0\xf9\x2d\x23".
       "\x0e\xfe\xe5\xf4\x8d\xb6\x6d\x37\x14\xed\x54\x97\x92\x5c\x68".
       "\x40\x88\xf1\x43\x29\xef\x5e\x96\x77\xa2\xe8\x3c\xae\x7f\xb1".
       "\x99\x17\xa7\x0c\x6f\xe2\x43\x32\x9b\x14\x43\xf2\x15\x6b\x13".
       "\x10\x68\x56\x0b\xaa\x06\x2e\xc0\xf8\xde\x9e\x54\x9d\xba\xff".
       "\x76\x26\x6d\x5e\x9e\x88\x3a\x2b\x9b\x20\x43\xb9\x1a\x0e\x58".
       "\x65\xec\xdb\x9e\x97\xb8\xfb\x03\x6c\xb0\x7f\xa2\xf1\xf4\x27".
       "\x24\x21\x47\x51\x21\x40\x45\x28\x71\xf7\xa1\x6b\xbe\x0e\xc8".
       "\x3f\x9b\xda\x62\x9d\x73\xf7\x5f\x70\x6c\xba\x1e\xeb\x16\x5c".
       "\x2e\x44\x0a\x22\x02\x6c\xbe\xb9\x69\x93\xfd\xa5\x33\x26\x64".
       "\x24\x6c\xc2\x3d\x2f\xf3\xd1\x97\xde\x60\x43\x1c\x0d\x1b\x94".
       "\xb3\x48\x45\x7c\xd5\xd0\x71\x4d\xad\xbf\xa4\x0a\x22\x27\x04".
       "\x38\x84\x19\x66\x63\xf0\xf3\xfc\xb0\xf3\x1d\xea\xba\xb9\xe4".
       "\xe5\x80\xed\xe3\xf1\x78\x24\xc3\x25\x27\x71\x81\xc2\xec\x54".
       "\xed\xcc\x63\xf7\x39\xcd\x83\xdf\x32\x88\xc0\x3b\xd4\x62\xb8".
       "\xea\x34\xd8\xcf\xbc\x3a\x89\x38\x64\x60\x44\xde\xb6\x76\x59".
       "\xb1\x95\x6a\x26\x08\xf0\xf4\x71\x25\x8b\xf8\x81\xdd\x0d\x2f".
       "\x8c\xe2\x70\xc2\x96\xc2\xd8\x9b\xe4\x3f\xec\x8b\xfd\xbd\xc9".
       "\x36\x33\xb7\xbc\x59\x37\x19\x09\x30\x5e\xef\x67\xae\x67\x48".
       "\x72\x0b\xf4\x2a\x82\xff\xcb\xd7\xd9\x9d\x6d\x7c\xa6\x20\x42".
       "\x50\x2b\x0a\x2f\x45\x99\x5b\x76\x6d\x99\x39\xa9\xb6\x32\x06".
       "\x11\xf8\x19\xd1\x3f\xc0\xd6\x1f\x67\xfa\xd5\xae\x7a\x71\x8c".
       "\xbc\x3d\xb4\x5f\x5c\x81\x7c\xa1\x39\x70\x0a\x17\x24\xb7\x22".
       "\x86\x50\xd8\x1f\xc8\x6c\x59\x9a\xdc\xf0\x71\x01\xda\xd8\x53".
       "\x98\x1c\x73\x36\xf1\x09\x86\xc9\xa7\x26\x25\xc0\x03\x3e\x13".
       "\x4e\x29\xeb\xf0\x8d\xe3\x38\x03\x54\xee\x37\xfb\x51\x2e\xb4".
       "\xf6\x12\x1f\xb2\x8c\x66\x75\x00\x30\x5b\xef\x59\xf9\x63\xa9".
       "\x74\x07\x91\xe4\x9c\xb7\xc9\x89\xd9\xa9\x51\x93\xcb\xb1\xa7".
       "\x64\x08\x79\x8f\xb4\x6d\x09\xd7\xc5\xbf\x0a\xdb\x50\xe0\x1c".
       "\x83\xca\xf8\xcf\xa7\x81\xbb\x0b\xe6\xcf\x1b\x0e\x0a\xe0\xcd".
       "\x68\xe2\xde\xc4\x2d\xba\x55\xc7\xc7\x1e\x6c\x5e\xca\x9b\x20".
       "\x75\x96\x94\x92\x84\xec\xf5\x22\x25\x78\x67\xcd\xbe\x01\xfe".
       "\x53\xa5\xcc\x6a\x40\x33\x83\xa4\x7a\x44\x93\x0b\xf9\x4c\xb2".
       "\x95\xb6\x7e\x4b\xa4\xc8\x86\xfe\x8a\xf1\x77\x40\x56\x13\xc1".
       "\x31\x2c\x8c\x4a\xa8\x89\x61\x0c\x39\x33\x78\x8c\xd5\x50\x3b".
       "\x89\xc3\xd3\x80\x1c\xa7\xb6\x36\xc2\x00\x8d\x0a\x7f\xcc\xd3".
       "\x20\x74\x60\x70\x36\x7d\xda\xdc\xc4\x49\x04\xf0\xe6\x6c\xd1".
       "\xbe\xcb\xfb\xf1\xa2\xd6\xd4\xe4\x97\x3f\x35\x09\x5b\xda\x06".
       "\x6b\x6d\x86\x53\x23\x0c\x26\x51\x2a\x15\xaa\xe2\x73\xfb\xc7".
       "\x41\x54\xdc\x5d\x99\x0b\x0a\x1e\xd4\xdb\x70\xa3\x8e\xfd\x5b".
       "\xf0\xa8\x3e\x9b\xff\x57\x98\xbc\xd9\x2a\x56\xd3\x19\xf9\x0b".
       "\xd9\x67\x0f\x10\x9c\x23\xe5\x6b\x12\xc6\xb6\x4b\xd1\x0c\xe9".
       "\x45\x36\xdf\x54\x6f\xcc\xfe\xb5\xcc\xb9\xfe\xde\xc8\xb5\xc9".
       "\x04\x59\x61\x75\x1e\x72\x37\x54\xfd\xc6\xc3\x7e\x74\xae\x55".
       "\x31\x6a\xbc\x8a\xd8\x45\x91\xe2\x8d\x20\x97\x71\xe7\x55\xd6".
       "\x8a\xb8\x82\x2a\x27\x4f\xdc\x53\x89\x28\xf7\x3a\xfe\x07\xef".
       "\x60\xb2\x32\x7c\xbc\x13\xc4\x3d\xda\xd7\xfb\xb8\x61\x7d\x69".
       "\xae\x0e\x9a\x71\xd6\x00\x26\x97\xff\xdb\xe6\xbe\x45\x7a\xb5".
       "\x00\x31\xfd\x70\xcc\xd7\x34\x88\xe4\x05\x61\xf5\x72\x1d\x14".
       "\xf0\x7e\x90\xdb\x0e\xc7\xda\xd4\xf3\x99\xd4\x60\xd9\xa7\xc8".
       "\x5b\x33\x34\xb5\x23\x74\x2c\x5f\x6b\x56\x95\x9c\x1b\x2a\xac".
       "\xf9\xfe\x46\xc3\xf1\x9b\x24\x7e\x4b\xca\x25\x58\x41\x10\x63".
       "\xe8\xe7\x68\xda\xcc\xb6\x4d\x5b\x8f\xc9\xa9\x31\xeb\x5c\x2a".
       "\xcf\x9d\x89\xd5\x51\x93\x80\x30\xf4\xc9\x2c\x8c\xb8\x8c\x62".
       "\xd6\x33\xbd\x95\x9f\xfa\x19\xf2\x48\x28\x09\x73\xc9\x53\x61".
       "\x94\x3a\x62\x68\x6c\xc6\xd6\x0a\xb4\xae\x27\x96\xfb\x29\xd7".
       "\x46\x67\x11\x7a\xe8\x3a\x9a\x3f\xf4\x9a\x75\xed\x24\x67\x45".
       "\x79\xdc\x8b\x19\xf2\xef\x57\xaa\xc7\x84\xff\x9d\x2d\xc3\xa8".
       "\x85\x54\xb7\x9d\xe1\xd6\x2b\xe9\x31\x9d\x6c\xb8\x4e\x76\x50".
       "\x80\x44\x46\x8f\x5e\x7e\x20\xaa\xa0\x8a\x36\x6b\xef\xd1\x75".
       "\xf8\x3f\x20\xdd\x09\x73\xbf\xa5\xf7\xb4\x87\xb2\x44\xc0\x0f".
       "\x10\xc0\x95\x2e\x8a\x42\xfa\xc3\x49\x17\xb9\xb5\x1a\xc3\x80".
       "\x93\x0c\xd8\xe3\xcd\xa4\x38\x61\x7a\x22\x73\x8e\x32\x8f\x55".
       "\x9c\x91\x08\xd9\x65\xa9\x02\x28\xc6\x59\xc8\x51\x32\x20\x48".
       "\xea\x2c\xae\x0e\xa6\x35\x5b\xe2\x63\xf9\xf2\x9d\x5f\xe3\x45".
       "\xdc\x41\xba\xfb\x40\xcc\x8d\xde\x6c\x3d\x50\x97\x9d\x83\xa0".
       "\xda\x41\x61\xba\xaf\xf8\x74\xd2\x21\x7b\x09\xcc\x83\xe1\x08".
       "\x01\x04\x42\xce\xcb\xec\x1d\x6b\xb7\x6f\x0f\x4b\xd4\x53\x90".
       "\x55\x3b\xcf\x9f\x93\xb8\xad\xce\x5f\x13\x83\xb3\x89\x6f\x5a".
       "\x1b\xa4\xf5\x95\x4b\xb4\x22\x22\x1d\x35\xaa\xfa\xc7\x14\x8c".
       "\xcd\x50\x66\x14\x47\xff\x67\xb2\xf8\x12\x09\xb3\x8a\xe5\x7d".
       "\xb8\xc9\xe4\x89\xf7\xa4\xb5\x70\xfa\x2d\xeb\x95\x89\xec\xbb".
       "\x49\x59\xd2\xc1\x6d\x0e\x06\xe4\x5e\xd5\x13\x13\x0d\x72\x6e".
       "\xf0\x6d\xa9\xd5\xe7\x54\x68\x35\xcd\xd0\xd5\xa6\xe5\xb2\xe4".
       "\xb1\x19\xe4\xf1\xe3\x8a\x56\x4c\x3b\x3d\xb8\x03\xfe\x22\x2f".
       "\xc6\xdc\x88\x7b\xca\x5c\xc6\xdd\x17\x34\x08\x22\xf0\x17\x61".
       "\x0e\x60\x9c\xb4\x27\x57\x30\x6e\xb8\x4f\xdd\x25\x7b\xef\x9e".
       "\x8e\x88\x6b\xd8\x10\x23\xc2\x44\x53\x73\x64\x8f\x40\x22\xe1".
       "\xe8\xa2\xb0\x3f\x8a\x07\x66\xcd\x64\x4f\x9c\x1e\x89\x76\x04".
       "\x6d\xab\xc2\xbb\x16\x85\x80\x01\xa5\xb1\xe2\x12\x04\x2e\x39".
       "\x87\x8c\xee\xbc\xfb\x07\x6d\x03\x4c\x3a\xa5\x7b\x95\xd9\xd7".
       "\xd6\xee\x2b\xe9\xcb\xe6\xec\xa8\x84\x6a\x42\xf9\xb2\x25\xc8".
       "\xf3\x6a\xaa\x34\x3b\xd9\x72\xd9\x70\x81\x3b\xd4\x5e\x66\x97".
       "\x1b\xe6\x2b\x88\x71\x82\xa3\x8a\x98\xb0\x16\xd9\xbb\x97\x8b".
       "\x57\x79\x41\x56\x6e\xc2\x8f\xdf\xfa\x5b\xc7\x68\x5b\xb8\x09".
       "\x41\x31\x7c\x19\xe1\x95\x2e\x05\x4c\xac\x38\x81\xda\xb3\x8b".
       "\x3e\x1c\x79\x9a\x31\xac\x3e\x3d\x6d\xab\xf3\x5a\x5e\xc7\x6e".
       "\x8e\x39\xcd\x7b\x6f\x62\xee\xb9\x73\xdd\x82\x42\x6f\x09\xe4".
       "\xc3\xae\x92\xe8\x18\x99\xa0\x5e\xa2\x12\xf4\xe2\xe0\xe6\x95".
       "\x58\x3a\x45\xad\xfe\x23\x79\x5f\x82\xce\x95\x88\x73\xeb\x46".
       "\xc8\x00\xac\xc3\x2a\xdc\x7e\xab\x9b\xf8\xbb\x46\x5c\xa8\x46".
       "\xbc\xfd\x99\xae\x4c\xa7\x77\xeb\x7c\x58\xbf\xbb\x52\x68\x62".
       "\x3d\x0b\x79\x64\x38\x65\xa7\xcb\x7b\xe9\xb2\x33\xb5\x59\x52".
       "\x7b\x17\xb4\x02\x2b\x07\x0d\x3a\x11\x57\x92\xa5\x22\x2b\xbc".
       "\xe6\x97\x05\x12\x05\xe7\x91\xe3\xfa\xae\x15\xbe\x20\xe5\x5c".
       "\x71\x24\x80\x85\xc9\x66\xc1\x53\x5c\x8f\x08\xd4\x52\xe1\x10".
       "\xb6\xd6\x20\x08\x01\x79\x33\x9f\x1b\xbd\xa0\xab\x7c\xb1\xd9".
       "\xdc\xca\x44\x22\x49\xb7\xb7\x3d\x84\xac\x92\xf4\xfa\x0a\xc9".
       "\xc5\xb2\x42\x2b\x9a\x63\xbb\x8a\x82\x04\x2f\xf7\xe9\x30\x05".
       "\x67\x32\xd1\x41\x1a\x69\x6e\xb9\xf8\x5f\x6d\xb7\xe5\x4e\x85".
       "\x21\xfa\x16\x8a\x44\xfd\xf6\xd9\xa2\x5f\x68\x2b\xf3\xe2\x3c".
       "\x8a\x69\xd2\xc1\x38\xed\x83\xef\x0d\x53\x86\x93\x32\x23\xc6".
       "\x14\x0c\xb0\xb6\x6e\x77\xa4\x20\x0f\xb1\x6e\xe2\xce\xca\x6f".
       "\x93\x1c\x3a\x8f\xd0\xd2\x5a\x6e\x30\xd6\x8e\x5f\x4b\xa5\xef".
       "\xa9\x62\xeb\x28\xa0\x5e\x3f\xc1\xbc\x0a\x68\xab\xd7\xfa\xa2".
       "\xb7\x8f\x12\xb0\x99\xbc\x93\x20\xb8\x95\x8d\xca\xc7\xa7\xd9".
       "\x2e\x19\xac\x06\xb9\x4e\x56\x8e\x74\xef\x2a\x04\xd8\x75\x04".
       "\x38\x2a\xc7\xa0\xa4\x89\xf3\xa4\x8a\xd4\x2c\x2c\x58\x6f\x00".
       "\x03\x23\xb8\xaf\x02\x48\x7d\x50\x46\x6f\x5a\x08\x41\xe3\x56".
       "\x6d\xcb\xe2\x4f\xea\x8e\xab\x74\xcd\xf9\xef\xcf\xf9\x1e\xf1".
       "\xf8\xb9\x6c\xaa\x3b\x37\xd1\x21\x42\x67\xec\xd6\x44\x55\x33".
       "\xe8\x1d\xa4\x18\xf3\x73\x82\xb4\x50\x59\xc2\x34\x36\x05\xeb";
 
     $expect = Filesystem::readFile(dirname(__FILE__).'/base85/expect2.txt');
-    $expect = trim($expect);
 
-    $this->assertEqual(
-      $expect,
-      ArcanistBundle::encodeBase85($data));
+    $this->assertBase85($expect, $data, pht('Random Data'));
+  }
+
+  private function assertBase85($expect, $data, $label) {
+    $modes = array(
+      '32bit',
+    );
+
+    // If this is a 64-bit machine, we can also test 64-bit mode.
+    $has_64bit = (PHP_INT_SIZE >= 8);
+    if ($has_64bit) {
+      $modes[] = '64bit';
+    }
+
+    foreach ($modes as $mode) {
+      $this->assertEqual(
+        $expect,
+        ArcanistBundle::newBase85Data($data, "\n", $mode),
+        pht('base85/%s: %s', $mode, $label));
+    }
   }
 
 }
diff --git a/src/parser/__tests__/base85/expect1.txt b/src/parser/__tests__/base85/expect1.txt
index 67fc430a..0844e377 100644
--- a/src/parser/__tests__/base85/expect1.txt
+++ b/src/parser/__tests__/base85/expect1.txt
@@ -1 +1,10 @@
-009C61O)~M2nh-c3=Iws5D^j+6crX17#SKH9337XAR!_nBqb&%C@Cr{EG;fCFflSSG&MFiI5|2yJUu=?KtV!7L`6nNNJ&adOifNtP*GA-R8>}2SXo+ITwPvYU}0ioWMyV&XlZI|Y;A6DaB*^Tbai%jczJqze0_d@fPsR8goTEOh>41ejE#<ukdcy;l$Dm3n3<ZJoSmMZprN9pq@|{(sHv)}tgWuEu(7hUw6(UkxVgH!yuH4^z`?@9#Kp$P$jQpf%+1cv(9zP<)YaD4*xB0K+}+;a;Njxq<mKk)=;`X~?CtLF@bU8V^!4`l`1$(#{Qds_|Ni~_`}+C#_xAPl^YZcV@9ypF>+0#~=jP?)<Kp4q-`?Ha+uGUK*Vfh4)6&t<&(6)v%gV{f$Hv9P!@|M9zrMY^ySll!x3;ykv$C<Uudc1EtE#D}r>3Q(qoSdppPrqZo0^%JmzI^3lai5;kB*Iui;9VehlYiOgMxv8e|~*@dwO|zcXoAjb8>NTZ*FaDYiem|XJ%z&V`5=oUtV2YTUuFIS5{S2Q&Le-PfkrtOG-&dM@B_NLqb77KR!J?J32WyH#RjiGcqwSFD@-CD=H}{CnhB%BO)OnA08bX8yXoH7Zw#16A}>+4-O3s3knGc2L=TM0|Eg6
+z009C61O)~M2nh-c3=Iws5D^j+6crX17#SKH9337XAR!_nBqb&%C@Cr{EG;fCFflSS
+zG&MFiI5|2yJUu=?KtV!7L`6nNNJ&adOifNtP*GA-R8>}2SXo+ITwPvYU}0ioWMyV&
+zXlZI|Y;A6DaB*^Tbai%jczJqze0_d@fPsR8goTEOh>41ejE#<ukdcy;l$Dm3n3<ZJ
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+z(9zP<)YaD4*xB0K+}+;a;Njxq<mKk)=;`X~?CtLF@bU8V^!4`l`1$(#{Qds_|Ni~_
+z`}+C#_xAPl^YZcV@9ypF>+0#~=jP?)<Kp4q-`?Ha+uGUK*Vfh4)6&t<&(6)v%gV{f
+z$Hv9P!@|M9zrMY^ySll!x3;ykv$C<Uudc1EtE#D}r>3Q(qoSdppPrqZo0^%JmzI^3
+zlai5;kB*Iui;9VehlYiOgMxv8e|~*@dwO|zcXoAjb8>NTZ*FaDYiem|XJ%z&V`5=o
+zUtV2YTUuFIS5{S2Q&Le-PfkrtOG-&dM@B_NLqb77KR!J?J32WyH#RjiGcqwSFD@-C
+rD=H}{CnhB%BO)OnA08bX8yXoH7Zw#16A}>+4-O3s3knGc2L=TM0|Eg6
diff --git a/src/parser/__tests__/base85/expect2.txt b/src/parser/__tests__/base85/expect2.txt
index 1f47b081..be01a9f0 100644
--- a/src/parser/__tests__/base85/expect2.txt
+++ b/src/parser/__tests__/base85/expect2.txt
@@ -1 +1,79 @@
-R!p;F<w~CeqfFghg@zC?Kfx$b*s>bKc@>2*X8DfcAdeEEln%ePoVCCeLp`nS06Z4@b}#LjI(R<Ok@&F6xhekC4;FA4t=U2qw2#)0fMV%Lcb_<IKh_RFXlRqJb!~rjoPcSRB8RrXVr#2OxRL3WzXZZiFs|ysaE_7Cw(M3Ec-4xGQqer#Wg+a7tIvM*{cSC2xh|tZdrhVLC~b73dpgB5d}FEkjx-cPu<;J!(9#5f|6<kIMmsi$ij!3WEdQTK)_TjoYBQ>92uzlkiBndzvzrF7pc85OYN!or+OltA3#j&4DMoz+MC*`m*T=TX#p~V>o4xX8j?fF*jO&ndb2H~}CRa}UmEinhlcy-=3`TR^0nS64P8M`qHj-LqOyi!AEt(oVX*p*E*7#pV?z_}u&y1TfX_y+AS4*i$_8WF6*W-_4m0JelsAgdKNlrjhGMjWZz*h7#?1R!QX<$_mJ5SaM_5?U}w!(r<`h!-wHA2J7+$i*ENU7jaL3w8WVbSuRd)~x8kB_#T3Uv5!12;D?jVfx%QK8~A<wDy}VNMqOBXSZ(QxbwcL}Md@s;hpDaAxt8h62StoOu@>pA(5aB}K_Q9-tZnARK{f{I$vA+OdZ;pt5o{Xc7fed}wPPDpo3ff6$y0sj^Jwie=Ylt@HCMoahh-isB$=<WWb#B9R3mIU4U&(u#;xKZCk+)Ro7$qWw)yUH{#$8p3|H`i5VVI9<w`T7I`j)m&@yG6NAr=}8hmf@ggyT48~`B&yeZ$<ME_KCna0&LQL*TGl}I4kPby^v2THHrF89jX6f@{CHKO0@imS$d?}9Mc$LAbl6!CB#P+G=>WA(=1H*L6dGOKI7hI@9_)N}$ss&Cg->yp?Mjp^QAnIakZ|b^gjLd{Nc#O$5)rvF{2gZJLgQX#^gZetQ{#I}?%Q<EFw+Ff+N9mBm^yaox*G#i?M7Yi)HK44@2*ib4^2R-I@?ehzF&*DBtRLDifcqqo8a`EOT;5L@U!7qoetTl_dbS0n_G}Pz#yQ-hEK-Jwae6q#&TDuS1dFpkwg`!^oYuIR-O`U-%{_uv|JYGs`s|@eA>-I`5ZuqL}*VNT6>SfM@ZB2<@IJYNWNs>{x$K#<f#0H`)MG_^cI%EdQlX2q;3=FSv4f_<^JiI4bkY%oPYQ`c{w^Aqj&F5OIdRRv;MAdDmw6aoqn6Du^9P7Y4cS^tvI6b%g#5ch#)xX87Y;Fbq1Xsp7OV3m?1WhlK8lZ9$Z}sJ5t4Jhki!NjNj+Vse2J)51vArKH!Uho{@HlnxW#BuKO4{+>)6z{g@!AiD4`z;JAaQ=TJhA{5EE5CB<#DG2u-QF8D;^wrXwugPtr0FBL)a=cX7dgnsKo%)8sER9w7SYTPC&^jW8Mq^#|8j}}7>mk=y)@1C;B-{z;A2zjITne|!Z)rk=0$@k|eat6j!!_CnDY53n6@@5=qK)jdnNnUtjQbvEzL{N)g=cwz|gd~B$EM@nVz4DGj`)Wx%YUL_9@cM~aUpaNOZv^q+EX{W`>}y39;}|3bxoE*oaZCS*80rmHNmbwFuvy!5o(nhwpAc`^GzUZ}2(i?6#)J*Kwbcm)83AG`MN%EcPbGMMysihc)ZiJB1J;c%0LijuJ5D`y_amA<q}6|QN6@^($ST~032Y3IIN0yc^m-e|cHrBAs2eMd)HaZI-inaOTLl2?vmnlHT)8zpl{$G!VCy3h`;aa6w*^W=L3vTC=8y_;hk(AYi4W6+8P06^yBifv4>M)=o;ul#0z=Q=vS7hX>7_ic`avzZA4M|DIWLs1L~Uuo$ybc!^rSkraAEnoLEL!o_rIu)<9AWcB`@D6YX>l&&f8g7s<JNJkdlH`{v|d^e{C%}QSUv-qlXLU@~n`c9oWa}lT$k(gf3ES`%f|2(dtD$-0M<-j4SjiyaB}LXf~YHEx}>SnqL?IYRH;S{V`k4kWNMaf9kR(t-(4WspxzZu7MuDqix!f8|(6Ec0Tbd_Zmgjvw^X`fPW;q4%KKhKN=|&4#Fm4463OhOkrh72fk_a$?Pv2`dKb=z!$|#`noS<tEsfh+{-0j&kTpm@HQ*Xfm$Mkpioekj@mYWbhRD=Ki9}95$hd2be|>~q&@i#@GV@aL%&gMjplgZXIJpZ4wsx)BQUIE-$t0EuTH1stTDaoYM`*>lzvh6iGe<=Ph_{nQE|<50;vL-T&oTgM>_<;n^_u@l1y<RUvAU$r$-w(K67c}?8{QKTzZuyKNgr^sG?oOT4&@D1_t?hv=rdHdlMZG^2!U;s&O?w)-Enxdlkte8mS~PNYu|t^fDKl9ZUX6Y1Y7xx!ZD5Ea>yZ{6_V-8wCc>%p)|vC2HzC$7IyivuEujC(~!ay`Ou183bI>mVTwjyRw96m^cxT`(hRS=C>qwvUtaHk;z~kk!=JkLFvi*<d{^0nr?QCA^DLwAKd;E2{6}FV`94FEO6EQcr`Y8UA7K2Jw}K7^<*DD{VyE5?UgOoW89}|Igh=|d6nr!zvMmzRRG&FC^~H7HM^{EQY)-Z5ky!PA+)XyYPsBnU62tbh1<jMIB$yo67b2M@cgcn5lzmPDG6-!Ds0*wOiH4bTJOd<TwtOo6IgSW-dQSFWNZ|aiY|^JKcYk4_AMiHT)lb_+ZU*l&~%2KGY3fStQc)%VS8aKq@t^tS-u(989^Rlhpj+cX^b-Uwn@Gpt=JDf*<!3ZcHT0hvO$%t7bB~oH=L_;d2rTd4Q@?~pseFW9t!U8bY$2>(QKyGHZIv!ZjfWQ_m0LWqd)*)nmqph127R7k}q2$;ZB+4g2_?h6>4@|XRf27oP|-~M2Taiahbd=oU5AqAU9anEsK3Z6E#Fk5tn8s7pz3+Y6Ezph{iT?T3T9iqv>)Ckum(Pd!Th83c*X2%j3fC0}r^eQOC%fjcq#TPAsbHUP+VSkD*kP=X_l;#{~c=6jw*H1uYknC`ImtI$5@+1i)MeALd&&Q(}T-)wc5WXBiRh(s0ETW5IRdB;^5FQhbOPwBQx#5(UkOde!Ph!@FhF-3{J0l$Z@H`#djc&?w@C*(dXQtx#x|R9@@6Ds<lSPKzfB&rD!I=*4oYjQ#1W|54@E>Yg-n;pX^Tu@Lb2Eh7&8<@AlVZ8sF{RF{%mXh4YZLn-fGmUp7)Jg$GSnHQ%FZ{kBTn-oLx6>Ad^XjTiV1}?z(-kwyQy8m`2ZC;*;IxCwXL%A9bSY_<no|m}$18lH=qVe=6Bq2vpAwWeaardEXz7EJgo7!TXbN63xY`Pxn7F;ew3L*k*zPV|W{iQP|WF&0DJumaom)>AQ91R<kvq(jJ)zEQGt-quSA}0hmgc)XI@bmnz^BwBCx#Z=5?c?!yB*P^qae>0@RPD@T_c_gj-!h26JJe#h>NMETygG?EWMD+zwsu*um1-sk@bqydi}-=v4KIx1aKe_t*qh`(?2G-q$u={$yjeFH2{2yoXRc>Ratrh-g8$3c*_~~CrXWI4D+(_~nOk;knK`MpG6oU&8PPw$)*om3)vkJRjJ!RxUtEEFp*e607bLeLhEUia$ZT1f-0*P$+SpT=9CJ4D35Ln1CMCcFJ`+wU>+p@^I0IDfH~Ud8wDuAovW#YR05DtcS@~nBbO({-oVUq|*{M;J%dw|q2zigRZ3)-KzY5z>;2eX>_|K<-y9?&e8x9KK&1mA@#4Wm2$HyLQUdo#wb(WNpgzWVqC3t7ez5)JIrOawTGlQghM3W2oOtO`>eoLgthW?82cR*GX!7(h1N~nop3^_A+jMY#(iNn)?9H+K6!T^m5f6UV$bYO5cecIf_Nd)lbY|*~U`|+aI)Z~{xH3?hV25W7GQzHx}Q7RRx;&c1QK~&sbnF|UY)Z1{Qj{RHks6LzjSD3unDpu1O`3u=+4-lLq<!chgwoB0r=|wi*RBz1wwamHx-pIAd1X*Eq9&$HS{l>$7bgoq~YP^crMUmo-AeV9HRo05Qf+{CZ+*64t_d5Ou?_jbre7qCHJ=)j%xM6*1t`3@U)&M4#|J&xiMS8UWG5v7N*EERa1!47a9Tf0>klPN&+SK!z)L_}C$XhcswIg&aUu#yCoEs{v`Tj=3@tY)mOUfl!K@el;=V;o@woO})$*D2xTq@6<iPce)fH3sQER48}V%9Ugm7n?<@<=ENbIDU-lsaN)Y{u3Kw5}(X`zhB(XAyenI+{Q9nsx0YXGMA3iy89oSE|Q^|D7$vsD)Iwo#ECi=`o#bxK4IZfJ8=*UVb2|po%tY@6mPmKOo%+bHAncw1=`pzz-0>l`e`x`ol>VxwRU@fRhZ^<ISWvVR|BSjxvu`oRJ9GWvK!v##zWwG9XCmEUpfwHCy6i`SP7#<3-#-y8A%PjoxfMP?w#9pxQxUy07?j(jj{Z%!A<w0R%$M%j_L%w{H(i)KidEJI|k!xUJ4#6N9sfZ(19q^_5GsA|f3%s`|$ijLlGH6i5GOviK4Svx?<?xXI*+_oTIO`Yr2~iR`;cS<=C64hH02)e{p9a&GW#snzFHXf@5y)u!dL<gpp#@#BhCOglZe1O6f}#@vW|%3Q|X7c>YW@E2hYV4SokS1@k4Pu(SZ@1Bl`YuFGY!bDSZWRE~1;pn2UKZ*xt&16rU9*K4YZL7k&7KMNTrLp1?1THy;jPAVq2W<mPI;DG++1J+YE9uMT?5KolLiw^K$n$EdG&|XH*>Hh7)Lv$n8|EvBae||Yn6MVvyO)bsc|lfg!jIqjTgPZyxCucqd>P@DE(J`iIDy);i#{BAnlY?CJ#DM=T3*L)jycVHZ({DbbKQbMZwchXu9D~&nV?>x67=HW=9O4FMXmlLd0&Fgm56ieM#uoH!z$c<tDE?{MqH>yy#1N3Os9A2d|1D`QfOj53wdNXWv9z~>9RAmSyFo!v;r#!4LT85lBFUmyylk$5(Vdx<NB@@z98jXaU_6+$!5V*T#pFUQsEG`)*uK0c{86Iy`ZanvDw_pL?TJIw>^ZclJxot$;GllE1F}wih=|$_vtVNXEM=28fk91_+M?e<xYhm`WA{r{r1_SUuY}y;yj9J(!n_GgYOMfhLbWQ#uN;&wr+Q%AP=!_;?Bx%lN>sa(9&9NFxHM=OQr9rV(TcNUO&OS3TUg>`l7dw60n)PlOVX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diff --git a/src/repository/api/ArcanistGitAPI.php b/src/repository/api/ArcanistGitAPI.php
index cfc92c36..6a011f44 100644
--- a/src/repository/api/ArcanistGitAPI.php
+++ b/src/repository/api/ArcanistGitAPI.php
@@ -1,1574 +1,1578 @@
 <?php
 
 /**
  * Interfaces with Git working copies.
  */
 final class ArcanistGitAPI extends ArcanistRepositoryAPI {
 
   private $repositoryHasNoCommits = false;
   const SEARCH_LENGTH_FOR_PARENT_REVISIONS = 16;
 
   /**
    * For the repository's initial commit, 'git diff HEAD^' and similar do
    * not work. Using this instead does work; it is the hash of the empty tree.
    */
   const GIT_MAGIC_ROOT_COMMIT = '4b825dc642cb6eb9a060e54bf8d69288fbee4904';
 
   private $symbolicHeadCommit;
   private $resolvedHeadCommit;
 
   protected function buildLocalFuture(array $argv) {
     $argv[0] = 'git '.$argv[0];
 
     $future = newv('ExecFuture', $argv);
     $future->setCWD($this->getPath());
     return $future;
   }
 
   public function execPassthru($pattern /* , ... */) {
     $args = func_get_args();
 
     static $git = null;
     if ($git === null) {
       if (phutil_is_windows()) {
         // NOTE: On Windows, phutil_passthru() uses 'bypass_shell' because
         // everything goes to hell if we don't. We must provide an absolute
         // path to Git for this to work properly.
         $git = Filesystem::resolveBinary('git');
         $git = csprintf('%s', $git);
       } else {
         $git = 'git';
       }
     }
 
     $args[0] = $git.' '.$args[0];
 
     return call_user_func_array('phutil_passthru', $args);
   }
 
 
   public function getSourceControlSystemName() {
     return 'git';
   }
 
   public function getGitVersion() {
     static $version = null;
     if ($version === null) {
       list($stdout) = $this->execxLocal('--version');
       $version = rtrim(str_replace('git version ', '', $stdout));
     }
     return $version;
   }
 
   public function getMetadataPath() {
     static $path = null;
     if ($path === null) {
       list($stdout) = $this->execxLocal('rev-parse --git-dir');
       $path = rtrim($stdout, "\n");
       // the output of git rev-parse --git-dir is an absolute path, unless
       // the cwd is the root of the repository, in which case it uses the
       // relative path of .git. If we get this relative path, turn it into
       // an absolute path.
       if ($path === '.git') {
         $path = $this->getPath('.git');
       }
     }
     return $path;
   }
 
   public function getHasCommits() {
     return !$this->repositoryHasNoCommits;
   }
 
   /**
    * Tests if a child commit is descendant of a parent commit.
    * If child and parent are the same, it returns false.
    * @param Child commit SHA.
    * @param Parent commit SHA.
    * @return bool True if the child is a descendant of the parent.
    */
   private function isDescendant($child, $parent) {
     list($common_ancestor) = $this->execxLocal(
       'merge-base %s %s',
       $child,
       $parent);
     $common_ancestor = trim($common_ancestor);
 
     return ($common_ancestor == $parent) && ($common_ancestor != $child);
   }
 
   public function getLocalCommitInformation() {
     if ($this->repositoryHasNoCommits) {
       // Zero commits.
       throw new Exception(
         pht(
           "You can't get local commit information for a repository with no ".
           "commits."));
     } else if ($this->getBaseCommit() == self::GIT_MAGIC_ROOT_COMMIT) {
       // One commit.
       $against = 'HEAD';
     } else {
 
       // 2..N commits. We include commits reachable from HEAD which are
       // not reachable from the base commit; this is consistent with user
       // expectations even though it is not actually the diff range.
       // Particularly:
       //
       //    |
       //    D <----- master branch
       //    |
       //    C  Y <- feature branch
       //    | /|
       //    B  X
       //    | /
       //    A
       //    |
       //
       // If "A, B, C, D" are master, and the user is at Y, when they run
       // "arc diff B" they want (and get) a diff of B vs Y, but they think about
       // this as being the commits X and Y. If we log "B..Y", we only show
       // Y. With "Y --not B", we show X and Y.
 
 
       if ($this->symbolicHeadCommit !== null) {
         $base_commit = $this->getBaseCommit();
         $resolved_base = $this->resolveCommit($base_commit);
 
         $head_commit = $this->symbolicHeadCommit;
         $resolved_head = $this->getHeadCommit();
 
         if (!$this->isDescendant($resolved_head, $resolved_base)) {
           // NOTE: Since the base commit will have been resolved as the
           // merge-base of the specified base and the specified HEAD, we can't
           // easily tell exactly what's wrong with the range.
 
           // For example, `arc diff HEAD --head HEAD^^^` is invalid because it
           // is reversed, but resolving the commit "HEAD" will compute its
           // merge-base with "HEAD^^^", which is "HEAD^^^", so the range will
           // appear empty.
 
           throw new ArcanistUsageException(
             pht(
               'The specified commit range is empty, backward or invalid: the '.
               'base (%s) is not an ancestor of the head (%s). You can not '.
               'diff an empty or reversed commit range.',
               $base_commit,
               $head_commit));
         }
       }
 
       $against = csprintf(
         '%s --not %s',
         $this->getHeadCommit(),
         $this->getBaseCommit());
     }
 
     // NOTE: Windows escaping of "%" symbols apparently is inherently broken;
     // when passed through escapeshellarg() they are replaced with spaces.
 
     // TODO: Learn how cmd.exe works and find some clever workaround?
 
     // NOTE: If we use "%x00", output is truncated in Windows.
 
     list($info) = $this->execxLocal(
       phutil_is_windows()
         ? 'log %C --format=%C --'
         : 'log %C --format=%s --',
       $against,
       // NOTE: "%B" is somewhat new, use "%s%n%n%b" instead.
       '%H%x01%T%x01%P%x01%at%x01%an%x01%aE%x01%s%x01%s%n%n%b%x02');
 
     $commits = array();
 
     $info = trim($info, " \n\2");
     if (!strlen($info)) {
       return array();
     }
 
     $info = explode("\2", $info);
     foreach ($info as $line) {
       list($commit, $tree, $parents, $time, $author, $author_email,
         $title, $message) = explode("\1", trim($line), 8);
       $message = rtrim($message);
 
       $commits[$commit] = array(
         'commit'  => $commit,
         'tree'    => $tree,
         'parents' => array_filter(explode(' ', $parents)),
         'time'    => $time,
         'author'  => $author,
         'summary' => $title,
         'message' => $message,
         'authorEmail' => $author_email,
       );
     }
 
     return $commits;
   }
 
   protected function buildBaseCommit($symbolic_commit) {
     if ($symbolic_commit !== null) {
       if ($symbolic_commit == self::GIT_MAGIC_ROOT_COMMIT) {
         $this->setBaseCommitExplanation(
           pht('you explicitly specified the empty tree.'));
         return $symbolic_commit;
       }
 
       list($err, $merge_base) = $this->execManualLocal(
         'merge-base %s %s',
         $symbolic_commit,
         $this->getHeadCommit());
       if ($err) {
         throw new ArcanistUsageException(
           pht(
             "Unable to find any git commit named '%s' in this repository.",
             $symbolic_commit));
       }
 
       if ($this->symbolicHeadCommit === null) {
         $this->setBaseCommitExplanation(
           pht(
             "it is the merge-base of the explicitly specified base commit ".
             "'%s' and HEAD.",
             $symbolic_commit));
       } else {
         $this->setBaseCommitExplanation(
           pht(
             "it is the merge-base of the explicitly specified base commit ".
             "'%s' and the explicitly specified head commit '%s'.",
             $symbolic_commit,
             $this->symbolicHeadCommit));
       }
 
       return trim($merge_base);
     }
 
     // Detect zero-commit or one-commit repositories. There is only one
     // relative-commit value that makes any sense in these repositories: the
     // empty tree.
     list($err) = $this->execManualLocal('rev-parse --verify HEAD^');
     if ($err) {
       list($err) = $this->execManualLocal('rev-parse --verify HEAD');
       if ($err) {
         $this->repositoryHasNoCommits = true;
       }
 
       if ($this->repositoryHasNoCommits) {
         $this->setBaseCommitExplanation(pht('the repository has no commits.'));
       } else {
         $this->setBaseCommitExplanation(
           pht('the repository has only one commit.'));
       }
 
       return self::GIT_MAGIC_ROOT_COMMIT;
     }
 
     if ($this->getBaseCommitArgumentRules() ||
         $this->getConfigurationManager()->getConfigFromAnySource('base')) {
       $base = $this->resolveBaseCommit();
       if (!$base) {
         throw new ArcanistUsageException(
           pht(
             "None of the rules in your 'base' configuration matched a valid ".
             "commit. Adjust rules or specify which commit you want to use ".
             "explicitly."));
       }
       return $base;
     }
 
     $do_write = false;
     $default_relative = null;
     $working_copy = $this->getWorkingCopyIdentity();
     if ($working_copy) {
       $default_relative = $working_copy->getProjectConfig(
         'git.default-relative-commit');
       $this->setBaseCommitExplanation(
         pht(
           "it is the merge-base of '%s' and HEAD, as specified in '%s' in ".
           "'%s'. This setting overrides other settings.",
           $default_relative,
           'git.default-relative-commit',
           '.arcconfig'));
     }
 
     if (!$default_relative) {
       list($err, $upstream) = $this->execManualLocal(
         'rev-parse --abbrev-ref --symbolic-full-name %s',
         '@{upstream}');
 
       if (!$err) {
         $default_relative = trim($upstream);
         $this->setBaseCommitExplanation(
           pht(
             "it is the merge-base of '%s' (the Git upstream ".
             "of the current branch) HEAD.",
             $default_relative));
       }
     }
 
     if (!$default_relative) {
       $default_relative = $this->readScratchFile('default-relative-commit');
       $default_relative = trim($default_relative);
       if ($default_relative) {
         $this->setBaseCommitExplanation(
           pht(
             "it is the merge-base of '%s' and HEAD, as specified in '%s'.",
             $default_relative,
             '.git/arc/default-relative-commit'));
       }
     }
 
     if (!$default_relative) {
 
       // TODO: Remove the history lesson soon.
 
       echo phutil_console_format(
         "<bg:green>** %s **</bg>\n\n",
         pht('Select a Default Commit Range'));
       echo phutil_console_wrap(
         pht(
           "You're running a command which operates on a range of revisions ".
           "(usually, from some revision to HEAD) but have not specified the ".
           "revision that should determine the start of the range.\n\n".
           "Previously, arc assumed you meant '%s' when you did not specify ".
           "a start revision, but this behavior does not make much sense in ".
           "most workflows outside of Facebook's historic %s workflow.\n\n".
           "arc no longer assumes '%s'. You must specify a relative commit ".
           "explicitly when you invoke a command (e.g., `%s`, not just `%s`) ".
           "or select a default for this working copy.\n\nIn most cases, the ".
           "best default is '%s'. You can also select '%s' to preserve the ".
           "old behavior, or some other remote or branch. But you almost ".
           "certainly want to select 'origin/master'.\n\n".
           "(Technically: the merge-base of the selected revision and HEAD is ".
           "used to determine the start of the commit range.)",
           'HEAD^',
           'git-svn',
           'HEAD^',
           'arc diff HEAD^',
           'arc diff',
           'origin/master',
           'HEAD^'));
 
       $prompt = pht('What default do you want to use? [origin/master]');
       $default = phutil_console_prompt($prompt);
 
       if (!strlen(trim($default))) {
         $default = 'origin/master';
       }
 
       $default_relative = $default;
       $do_write = true;
     }
 
     list($object_type) = $this->execxLocal(
       'cat-file -t %s',
       $default_relative);
 
     if (trim($object_type) !== 'commit') {
       throw new Exception(
         pht(
           "Relative commit '%s' is not the name of a commit!",
           $default_relative));
     }
 
     if ($do_write) {
       // Don't perform this write until we've verified that the object is a
       // valid commit name.
       $this->writeScratchFile('default-relative-commit', $default_relative);
       $this->setBaseCommitExplanation(
         pht(
           "it is the merge-base of '%s' and HEAD, as you just specified.",
           $default_relative));
     }
 
     list($merge_base) = $this->execxLocal(
       'merge-base %s HEAD',
       $default_relative);
 
     return trim($merge_base);
   }
 
   public function getHeadCommit() {
     if ($this->resolvedHeadCommit === null) {
       $this->resolvedHeadCommit = $this->resolveCommit(
         coalesce($this->symbolicHeadCommit, 'HEAD'));
     }
 
     return $this->resolvedHeadCommit;
   }
 
   public function setHeadCommit($symbolic_commit) {
     $this->symbolicHeadCommit = $symbolic_commit;
     $this->reloadCommitRange();
     return $this;
   }
 
   /**
    * Translates a symbolic commit (like "HEAD^") to a commit identifier.
    * @param string_symbol commit.
    * @return string the commit SHA.
    */
   private function resolveCommit($symbolic_commit) {
     list($err, $commit_hash) = $this->execManualLocal(
       'rev-parse %s',
       $symbolic_commit);
 
     if ($err) {
       throw new ArcanistUsageException(
         pht(
           "Unable to find any git commit named '%s' in this repository.",
           $symbolic_commit));
     }
 
     return trim($commit_hash);
   }
 
   private function getDiffFullOptions($detect_moves_and_renames = true) {
     $options = array(
       self::getDiffBaseOptions(),
       '--no-color',
       '--src-prefix=a/',
       '--dst-prefix=b/',
       '-U'.$this->getDiffLinesOfContext(),
     );
 
     if ($detect_moves_and_renames) {
       $options[] = '-M';
       $options[] = '-C';
     }
 
     return implode(' ', $options);
   }
 
   private function getDiffBaseOptions() {
     $options = array(
       // Disable external diff drivers, like graphical differs, since Arcanist
       // needs to capture the diff text.
       '--no-ext-diff',
       // Disable textconv so we treat binary files as binary, even if they have
       // an alternative textual representation. TODO: Ideally, Differential
       // would ship up the binaries for 'arc patch' but display the textconv
       // output in the visual diff.
       '--no-textconv',
       // Provide a standard view of submodule changes; the 'log' and 'diff'
       // values do not parse by the diff parser.
       '--submodule=short',
     );
     return implode(' ', $options);
   }
 
   /**
    * @param the base revision
    * @param head revision. If this is null, the generated diff will include the
    * working copy
    */
   public function getFullGitDiff($base, $head = null) {
     $options = $this->getDiffFullOptions();
 
     if ($head !== null) {
       list($stdout) = $this->execxLocal(
         "diff {$options} %s %s --",
         $base,
         $head);
     } else {
       list($stdout) = $this->execxLocal(
         "diff {$options} %s --",
         $base);
     }
 
     return $stdout;
   }
 
   /**
    * @param string Path to generate a diff for.
    * @param bool   If true, detect moves and renames. Otherwise, ignore
    *               moves/renames; this is useful because it prompts git to
    *               generate real diff text.
    */
   public function getRawDiffText($path, $detect_moves_and_renames = true) {
     $options = $this->getDiffFullOptions($detect_moves_and_renames);
     list($stdout) = $this->execxLocal(
       "diff {$options} %s -- %s",
       $this->getBaseCommit(),
       $path);
     return $stdout;
   }
 
   private function getBranchNameFromRef($ref) {
     $count = 0;
     $branch = preg_replace('/^refs\/heads\//', '', $ref, 1, $count);
     if ($count !== 1) {
       return null;
     }
 
     if (!strlen($branch)) {
       return null;
     }
 
     return $branch;
   }
 
   public function getBranchName() {
     list($err, $stdout, $stderr) = $this->execManualLocal(
       'symbolic-ref --quiet HEAD');
 
     if ($err === 0) {
       // We expect the branch name to come qualified with a refs/heads/ prefix.
       // Verify this, and strip it.
       $ref = rtrim($stdout);
       $branch = $this->getBranchNameFromRef($ref);
       if ($branch === null) {
         throw new Exception(
           pht('Failed to parse %s output!', 'git symbolic-ref'));
       }
       return $branch;
     } else if ($err === 1) {
       // Exit status 1 with --quiet indicates that HEAD is detached.
       return null;
     } else {
       throw new Exception(
         pht('Command %s failed: %s', 'git symbolic-ref', $stderr));
     }
   }
 
   public function getRemoteURI() {
     // Determine which remote to examine; default to 'origin'
     $remote = 'origin';
     $branch = $this->getBranchName();
     if ($branch) {
       $path = $this->getPathToUpstream($branch);
       if ($path->isConnectedToRemote()) {
         $remote = $path->getRemoteRemoteName();
       }
     }
 
     // "git ls-remote --get-url" is the appropriate plumbing to get the remote
     // URI. "git config remote.origin.url", on the other hand, may not be as
     // accurate (for example, it does not take into account possible URL
     // rewriting rules set by the user through "url.<base>.insteadOf"). However,
     // the --get-url flag requires git 1.7.5.
     $version = $this->getGitVersion();
     if (version_compare($version, '1.7.5', '>=')) {
       list($stdout) = $this->execxLocal('ls-remote --get-url %s', $remote);
     } else {
       list($stdout) = $this->execxLocal('config %s', "remote.{$remote}.url");
     }
 
     $uri = rtrim($stdout);
     // ls-remote echos the remote name (ie 'origin') if no remote URI is found
     // TODO: In 2.7.0 (circa 2016) git introduced `git remote get-url`
     // with saner error handling.
     if (!$uri || $uri === $remote) {
       return null;
     }
 
     return $uri;
   }
 
   public function getSourceControlPath() {
     // TODO: Try to get something useful here.
     return null;
   }
 
   public function getGitCommitLog() {
     $relative = $this->getBaseCommit();
     if ($this->repositoryHasNoCommits) {
       // No commits yet.
       return '';
     } else if ($relative == self::GIT_MAGIC_ROOT_COMMIT) {
       // First commit.
       list($stdout) = $this->execxLocal(
         'log --format=medium HEAD');
     } else {
       // 2..N commits.
       list($stdout) = $this->execxLocal(
         'log --first-parent --format=medium %s..%s',
         $this->getBaseCommit(),
         $this->getHeadCommit());
     }
     return $stdout;
   }
 
   public function getGitHistoryLog() {
     list($stdout) = $this->execxLocal(
       'log --format=medium -n%d %s',
       self::SEARCH_LENGTH_FOR_PARENT_REVISIONS,
       $this->getBaseCommit());
     return $stdout;
   }
 
   public function getSourceControlBaseRevision() {
     list($stdout) = $this->execxLocal(
       'rev-parse %s',
       $this->getBaseCommit());
     return rtrim($stdout, "\n");
   }
 
   public function getCanonicalRevisionName($string) {
     $match = null;
     if (preg_match('/@([0-9]+)$/', $string, $match)) {
       $stdout = $this->getHashFromFromSVNRevisionNumber($match[1]);
     } else {
       list($stdout) = $this->execxLocal(
         phutil_is_windows()
         ? 'show -s --format=%C %s --'
         : 'show -s --format=%s %s --',
         '%H',
         $string);
     }
     return rtrim($stdout);
   }
 
   private function executeSVNFindRev($input, $vcs) {
     $match = array();
     list($stdout) = $this->execxLocal(
       'svn find-rev %s',
       $input);
     if (!$stdout) {
       throw new ArcanistUsageException(
         pht(
           'Cannot find the %s equivalent of %s.',
           $vcs,
           $input));
     }
     // When git performs a partial-rebuild during svn
     // look-up, we need to parse the final line
     $lines = explode("\n", $stdout);
     $stdout = $lines[count($lines) - 2];
     return rtrim($stdout);
   }
 
   // Convert svn revision number to git hash
   public function getHashFromFromSVNRevisionNumber($revision_id) {
     return $this->executeSVNFindRev('r'.$revision_id, 'Git');
   }
 
 
   // Convert a git hash to svn revision number
   public function getSVNRevisionNumberFromHash($hash) {
     return $this->executeSVNFindRev($hash, 'SVN');
   }
 
   private function buildUncommittedStatusViaStatus() {
     $status = $this->buildLocalFuture(
       array(
         'status --porcelain=2 -z',
       ));
     list($stdout) = $status->resolvex();
 
     $result = new PhutilArrayWithDefaultValue();
     $parts = explode("\0", $stdout);
     while (count($parts) > 1) {
       $entry = array_shift($parts);
-      $entry_parts = explode(' ', $entry);
+      $entry_parts = explode(' ', $entry, 2);
       if ($entry_parts[0] == '1') {
+        $entry_parts = explode(' ', $entry, 9);
         $path = $entry_parts[8];
       } else if ($entry_parts[0] == '2') {
+        $entry_parts = explode(' ', $entry, 10);
         $path = $entry_parts[9];
       } else if ($entry_parts[0] == 'u') {
+        $entry_parts = explode(' ', $entry, 11);
         $path = $entry_parts[10];
       } else if ($entry_parts[0] == '?') {
+        $entry_parts = explode(' ', $entry, 2);
         $result[$entry_parts[1]] = self::FLAG_UNTRACKED;
         continue;
       }
 
       $result[$path] |= self::FLAG_UNCOMMITTED;
       $index_state = substr($entry_parts[1], 0, 1);
       $working_state = substr($entry_parts[1], 1, 1);
       if ($index_state == 'A') {
         $result[$path] |= self::FLAG_ADDED;
       } else if ($index_state == 'M') {
         $result[$path] |= self::FLAG_MODIFIED;
       } else if ($index_state == 'D') {
         $result[$path] |= self::FLAG_DELETED;
       }
       if ($working_state != '.') {
         $result[$path] |= self::FLAG_UNSTAGED;
         if ($index_state == '.') {
           if ($working_state == 'A') {
             $result[$path] |= self::FLAG_ADDED;
           } else if ($working_state == 'M') {
             $result[$path] |= self::FLAG_MODIFIED;
           } else if ($working_state == 'D') {
             $result[$path] |= self::FLAG_DELETED;
           }
         }
       }
       $submodule_tracked = substr($entry_parts[2], 2, 1);
       $submodule_untracked = substr($entry_parts[2], 3, 1);
       if ($submodule_tracked == 'M' || $submodule_untracked == 'U') {
         $result[$path] |= self::FLAG_EXTERNALS;
       }
 
       if ($entry_parts[0] == '2') {
         $result[array_shift($parts)] = $result[$path] | self::FLAG_DELETED;
         $result[$path] |= self::FLAG_ADDED;
       }
     }
     return $result->toArray();
   }
 
   protected function buildUncommittedStatus() {
     if (version_compare($this->getGitVersion(), '2.11.0', '>=')) {
       return $this->buildUncommittedStatusViaStatus();
     }
 
     $diff_options = $this->getDiffBaseOptions();
 
     if ($this->repositoryHasNoCommits) {
       $diff_base = self::GIT_MAGIC_ROOT_COMMIT;
     } else {
       $diff_base = 'HEAD';
     }
 
     // Find uncommitted changes.
     $uncommitted_future = $this->buildLocalFuture(
       array(
         'diff %C --raw %s --',
         $diff_options,
         $diff_base,
       ));
 
     $untracked_future = $this->buildLocalFuture(
       array(
         'ls-files --others --exclude-standard',
       ));
 
     // Unstaged changes
     $unstaged_future = $this->buildLocalFuture(
       array(
         'diff-files --name-only',
       ));
 
     $futures = array(
       $uncommitted_future,
       $untracked_future,
       // NOTE: `git diff-files` races with each of these other commands
       // internally, and resolves with inconsistent results if executed
       // in parallel. To work around this, DO NOT run it at the same time.
       // After the other commands exit, we can start the `diff-files` command.
     );
 
     id(new FutureIterator($futures))->resolveAll();
 
     // We're clear to start the `git diff-files` now.
     $unstaged_future->start();
 
     $result = new PhutilArrayWithDefaultValue();
 
     list($stdout) = $uncommitted_future->resolvex();
     $uncommitted_files = $this->parseGitRawDiff($stdout);
     foreach ($uncommitted_files as $path => $mask) {
       $result[$path] |= ($mask | self::FLAG_UNCOMMITTED);
     }
 
     list($stdout) = $untracked_future->resolvex();
     $stdout = rtrim($stdout, "\n");
     if (strlen($stdout)) {
       $stdout = explode("\n", $stdout);
       foreach ($stdout as $path) {
         $result[$path] |= self::FLAG_UNTRACKED;
       }
     }
 
     list($stdout, $stderr) = $unstaged_future->resolvex();
     $stdout = rtrim($stdout, "\n");
     if (strlen($stdout)) {
       $stdout = explode("\n", $stdout);
       foreach ($stdout as $path) {
         $result[$path] |= self::FLAG_UNSTAGED;
       }
     }
 
     return $result->toArray();
   }
 
   protected function buildCommitRangeStatus() {
     list($stdout, $stderr) = $this->execxLocal(
       'diff %C --raw %s HEAD --',
       $this->getDiffBaseOptions(),
       $this->getBaseCommit());
 
     return $this->parseGitRawDiff($stdout);
   }
 
   public function getGitConfig($key, $default = null) {
     list($err, $stdout) = $this->execManualLocal('config %s', $key);
     if ($err) {
       return $default;
     }
     return rtrim($stdout);
   }
 
   public function getAuthor() {
     list($stdout) = $this->execxLocal('var GIT_AUTHOR_IDENT');
     return preg_replace('/\s+<.*/', '', rtrim($stdout, "\n"));
   }
 
   public function addToCommit(array $paths) {
     $this->execxLocal(
       'add -A -- %Ls',
       $paths);
     $this->reloadWorkingCopy();
     return $this;
   }
 
   public function doCommit($message) {
     $tmp_file = new TempFile();
     Filesystem::writeFile($tmp_file, $message);
 
     // NOTE: "--allow-empty-message" was introduced some time after 1.7.0.4,
     // so we do not provide it and thus require a message.
 
     $this->execxLocal(
       'commit -F %s',
       $tmp_file);
 
     $this->reloadWorkingCopy();
 
     return $this;
   }
 
   public function amendCommit($message = null) {
     if ($message === null) {
       $this->execxLocal('commit --amend --allow-empty -C HEAD');
     } else {
       $tmp_file = new TempFile();
       Filesystem::writeFile($tmp_file, $message);
       $this->execxLocal(
         'commit --amend --allow-empty -F %s',
         $tmp_file);
     }
 
     $this->reloadWorkingCopy();
     return $this;
   }
 
   private function parseGitRawDiff($status, $full = false) {
     static $flags = array(
       'A' => self::FLAG_ADDED,
       'M' => self::FLAG_MODIFIED,
       'D' => self::FLAG_DELETED,
     );
 
     $status = trim($status);
     $lines = array();
     foreach (explode("\n", $status) as $line) {
       if ($line) {
         $lines[] = preg_split("/[ \t]/", $line, 6);
       }
     }
 
     $files = array();
     foreach ($lines as $line) {
       $mask = 0;
 
       // "git diff --raw" lines begin with a ":" character.
       $old_mode = ltrim($line[0], ':');
       $new_mode = $line[1];
 
       // The hashes may be padded with "." characters for alignment. Discard
       // them.
       $old_hash = rtrim($line[2], '.');
       $new_hash = rtrim($line[3], '.');
 
       $flag = $line[4];
       $file = $line[5];
 
       $new_value = intval($new_mode, 8);
       $is_submodule = (($new_value & 0160000) === 0160000);
 
       if (($is_submodule) &&
           ($flag == 'M') &&
           ($old_hash === $new_hash) &&
           ($old_mode === $new_mode)) {
         // See T9455. We see this submodule as "modified", but the old and new
         // hashes are the same and the old and new modes are the same, so we
         // don't directly see a modification.
 
         // We can end up here if we have a submodule which has uncommitted
         // changes inside of it (for example, the user has added untracked
         // files or made uncommitted changes to files in the submodule). In
         // this case, we set a different flag because we can't meaningfully
         // give users the same prompt.
 
         // Note that if the submodule has real changes from the parent
         // perspective (the base commit has changed) and also has uncommitted
         // changes, we'll only see the real changes and miss the uncommitted
         // changes. At the time of writing, there is no reasonable porcelain
         // for finding those changes, and the impact of this error seems small.
 
         $mask |= self::FLAG_EXTERNALS;
       } else if (isset($flags[$flag])) {
         $mask |= $flags[$flag];
       } else if ($flag[0] == 'R') {
         $both = explode("\t", $file);
         if ($full) {
           $files[$both[0]] = array(
             'mask' => $mask | self::FLAG_DELETED,
             'ref'  => str_repeat('0', 40),
           );
         } else {
           $files[$both[0]] = $mask | self::FLAG_DELETED;
         }
         $file = $both[1];
         $mask |= self::FLAG_ADDED;
       } else if ($flag[0] == 'C') {
         $both = explode("\t", $file);
         $file = $both[1];
         $mask |= self::FLAG_ADDED;
       }
 
       if ($full) {
         $files[$file] = array(
           'mask' => $mask,
           'ref'  => $new_hash,
         );
       } else {
         $files[$file] = $mask;
       }
     }
 
     return $files;
   }
 
   public function getAllFiles() {
     $future = $this->buildLocalFuture(array('ls-files -z'));
     return id(new LinesOfALargeExecFuture($future))
       ->setDelimiter("\0");
   }
 
   public function getChangedFiles($since_commit) {
     list($stdout) = $this->execxLocal(
       'diff --raw %s',
       $since_commit);
     return $this->parseGitRawDiff($stdout);
   }
 
   public function getBlame($path) {
     list($stdout) = $this->execxLocal(
       'blame --porcelain -w -M %s -- %s',
       $this->getBaseCommit(),
       $path);
 
     // the --porcelain format prints at least one header line per source line,
     // then the source line prefixed by a tab character
     $blame_info = preg_split('/^\t.*\n/m', rtrim($stdout));
 
     // commit info is not repeated in these headers, so cache it
     $revision_data = array();
 
     $blame = array();
     foreach ($blame_info as $line_info) {
       $revision = substr($line_info, 0, 40);
       $data = idx($revision_data, $revision, array());
 
       if (empty($data)) {
         $matches = array();
         if (!preg_match('/^author (.*)$/m', $line_info, $matches)) {
           throw new Exception(
             pht(
               'Unexpected output from %s: no author for commit %s',
               'git blame',
               $revision));
         }
         $data['author'] = $matches[1];
         $data['from_first_commit'] = preg_match('/^boundary$/m', $line_info);
         $revision_data[$revision] = $data;
       }
 
       // Ignore lines predating the git repository (on a boundary commit)
       // rather than blaming them on the oldest diff's unfortunate author
       if (!$data['from_first_commit']) {
         $blame[] = array($data['author'], $revision);
       }
     }
 
     return $blame;
   }
 
   public function getOriginalFileData($path) {
     return $this->getFileDataAtRevision($path, $this->getBaseCommit());
   }
 
   public function getCurrentFileData($path) {
     return $this->getFileDataAtRevision($path, 'HEAD');
   }
 
   private function parseGitTree($stdout) {
     $result = array();
 
     $stdout = trim($stdout);
     if (!strlen($stdout)) {
       return $result;
     }
 
     $lines = explode("\n", $stdout);
     foreach ($lines as $line) {
       $matches = array();
       $ok = preg_match(
         '/^(\d{6}) (blob|tree|commit) ([a-z0-9]{40})[\t](.*)$/',
         $line,
         $matches);
       if (!$ok) {
         throw new Exception(pht('Failed to parse %s output!', 'git ls-tree'));
       }
       $result[$matches[4]] = array(
         'mode' => $matches[1],
         'type' => $matches[2],
         'ref'  => $matches[3],
       );
     }
     return $result;
   }
 
   private function getFileDataAtRevision($path, $revision) {
     // NOTE: We don't want to just "git show {$revision}:{$path}" since if the
     // path was a directory at the given revision we'll get a list of its files
     // and treat it as though it as a file containing a list of other files,
     // which is silly.
 
     list($stdout) = $this->execxLocal(
       'ls-tree %s -- %s',
       $revision,
       $path);
 
     $info = $this->parseGitTree($stdout);
     if (empty($info[$path])) {
       // No such path, or the path is a directory and we executed 'ls-tree dir/'
       // and got a list of its contents back.
       return null;
     }
 
     if ($info[$path]['type'] != 'blob') {
       // Path is or was a directory, not a file.
       return null;
     }
 
     list($stdout) = $this->execxLocal(
       'cat-file blob %s',
        $info[$path]['ref']);
     return $stdout;
   }
 
   /**
    * Returns names of all the branches in the current repository.
    *
    * @return list<dict<string, string>> Dictionary of branch information.
    */
   public function getAllBranches() {
     $field_list = array(
       '%(refname)',
       '%(objectname)',
       '%(committerdate:raw)',
       '%(tree)',
       '%(subject)',
       '%(subject)%0a%0a%(body)',
       '%02',
     );
 
     list($stdout) = $this->execxLocal(
       'for-each-ref --format=%s -- refs/heads',
       implode('%01', $field_list));
 
     $current = $this->getBranchName();
     $result = array();
 
     $lines = explode("\2", $stdout);
     foreach ($lines as $line) {
       $line = trim($line);
       if (!strlen($line)) {
         continue;
       }
 
       $fields = explode("\1", $line, 6);
       list($ref, $hash, $epoch, $tree, $desc, $text) = $fields;
 
       $branch = $this->getBranchNameFromRef($ref);
       if ($branch !== null) {
         $result[] = array(
           'current' => ($branch === $current),
           'name' => $branch,
           'ref' => $ref,
           'hash' => $hash,
           'tree' => $tree,
           'epoch' => (int)$epoch,
           'desc' => $desc,
           'text' => $text,
         );
       }
     }
 
     return $result;
   }
 
   public function getAllBranchRefs() {
     $branches = $this->getAllBranches();
 
     $refs = array();
     foreach ($branches as $branch) {
       $commit_ref = $this->newCommitRef()
         ->setCommitHash($branch['hash'])
         ->setTreeHash($branch['tree'])
         ->setCommitEpoch($branch['epoch'])
         ->attachMessage($branch['text']);
 
       $refs[] = $this->newBranchRef()
         ->setBranchName($branch['name'])
         ->setRefName($branch['ref'])
         ->setIsCurrentBranch($branch['current'])
         ->attachCommitRef($commit_ref);
     }
 
     return $refs;
   }
 
   public function getBaseCommitRef() {
     $base_commit = $this->getBaseCommit();
 
     if ($base_commit === self::GIT_MAGIC_ROOT_COMMIT) {
       return null;
     }
 
     $base_message = $this->getCommitMessage($base_commit);
 
     // TODO: We should also pull the tree hash.
 
     return $this->newCommitRef()
       ->setCommitHash($base_commit)
       ->attachMessage($base_message);
   }
 
   public function getWorkingCopyRevision() {
     list($stdout) = $this->execxLocal('rev-parse HEAD');
     return rtrim($stdout, "\n");
   }
 
   public function isHistoryDefaultImmutable() {
     return false;
   }
 
   public function supportsAmend() {
     return true;
   }
 
   public function supportsCommitRanges() {
     return true;
   }
 
   public function supportsLocalCommits() {
     return true;
   }
 
   public function hasLocalCommit($commit) {
     try {
       if (!$this->getCanonicalRevisionName($commit)) {
         return false;
       }
     } catch (CommandException $exception) {
       return false;
     }
     return true;
   }
 
   public function getAllLocalChanges() {
     $diff = $this->getFullGitDiff($this->getBaseCommit());
     if (!strlen(trim($diff))) {
       return array();
     }
     $parser = new ArcanistDiffParser();
     return $parser->parseDiff($diff);
   }
 
   public function supportsLocalBranchMerge() {
     return true;
   }
 
   public function performLocalBranchMerge($branch, $message) {
     if (!$branch) {
       throw new ArcanistUsageException(
         pht('Under git, you must specify the branch you want to merge.'));
     }
     $err = phutil_passthru(
       '(cd %s && git merge --no-ff -m %s %s)',
       $this->getPath(),
       $message,
       $branch);
 
     if ($err) {
       throw new ArcanistUsageException(pht('Merge failed!'));
     }
   }
 
   public function getFinalizedRevisionMessage() {
     return pht(
       "You may now push this commit upstream, as appropriate (e.g. with ".
       "'%s', or '%s', or by printing and faxing it).",
       'git push',
       'git svn dcommit');
   }
 
   public function getCommitMessage($commit) {
     list($message) = $this->execxLocal(
       'log -n1 --format=%C %s --',
       '%s%n%n%b',
       $commit);
     return $message;
   }
 
   public function loadWorkingCopyDifferentialRevisions(
     ConduitClient $conduit,
     array $query) {
 
     $messages = $this->getGitCommitLog();
     if (!strlen($messages)) {
       return array();
     }
 
     $parser = new ArcanistDiffParser();
     $messages = $parser->parseDiff($messages);
 
     // First, try to find revisions by explicit revision IDs in commit messages.
     $reason_map = array();
     $revision_ids = array();
     foreach ($messages as $message) {
       $object = ArcanistDifferentialCommitMessage::newFromRawCorpus(
         $message->getMetadata('message'));
       if ($object->getRevisionID()) {
         $revision_ids[] = $object->getRevisionID();
         $reason_map[$object->getRevisionID()] = $message->getCommitHash();
       }
     }
 
     if ($revision_ids) {
       $results = $conduit->callMethodSynchronous(
         'differential.query',
         $query + array(
           'ids' => $revision_ids,
         ));
 
       foreach ($results as $key => $result) {
         $hash = substr($reason_map[$result['id']], 0, 16);
         $results[$key]['why'] = pht(
           "Commit message for '%s' has explicit 'Differential Revision'.",
           $hash);
       }
 
       return $results;
     }
 
     // If we didn't succeed, try to find revisions by hash.
     $hashes = array();
     foreach ($this->getLocalCommitInformation() as $commit) {
       $hashes[] = array('gtcm', $commit['commit']);
       $hashes[] = array('gttr', $commit['tree']);
     }
 
     $results = $conduit->callMethodSynchronous(
       'differential.query',
       $query + array(
         'commitHashes' => $hashes,
       ));
 
     foreach ($results as $key => $result) {
       $results[$key]['why'] = pht(
         'A git commit or tree hash in the commit range is already attached '.
         'to the Differential revision.');
     }
 
     return $results;
   }
 
   public function updateWorkingCopy() {
     $this->execxLocal('pull');
     $this->reloadWorkingCopy();
   }
 
   public function getCommitSummary($commit) {
     if ($commit == self::GIT_MAGIC_ROOT_COMMIT) {
       return pht('(The Empty Tree)');
     }
 
     list($summary) = $this->execxLocal(
       'log -n 1 --format=%C %s',
       '%s',
       $commit);
 
     return trim($summary);
   }
 
   public function backoutCommit($commit_hash) {
     $this->execxLocal('revert %s -n --no-edit', $commit_hash);
     $this->reloadWorkingCopy();
     if (!$this->getUncommittedStatus()) {
       throw new ArcanistUsageException(
         pht('%s has already been reverted.', $commit_hash));
     }
   }
 
   public function getBackoutMessage($commit_hash) {
     return pht('This reverts commit %s.', $commit_hash);
   }
 
   public function isGitSubversionRepo() {
     return Filesystem::pathExists($this->getPath('.git/svn'));
   }
 
   public function resolveBaseCommitRule($rule, $source) {
     list($type, $name) = explode(':', $rule, 2);
 
     switch ($type) {
       case 'git':
         $matches = null;
         if (preg_match('/^merge-base\((.+)\)$/', $name, $matches)) {
           list($err, $merge_base) = $this->execManualLocal(
             'merge-base %s HEAD',
             $matches[1]);
           if (!$err) {
             $this->setBaseCommitExplanation(
               pht(
                 "it is the merge-base of '%s' and HEAD, as specified by ".
                 "'%s' in your %s 'base' configuration.",
                 $matches[1],
                 $rule,
                 $source));
             return trim($merge_base);
           }
         } else if (preg_match('/^branch-unique\((.+)\)$/', $name, $matches)) {
           list($err, $merge_base) = $this->execManualLocal(
             'merge-base %s HEAD',
             $matches[1]);
           if ($err) {
             return null;
           }
           $merge_base = trim($merge_base);
 
           list($commits) = $this->execxLocal(
             'log --format=%C %s..HEAD --',
             '%H',
             $merge_base);
           $commits = array_filter(explode("\n", $commits));
 
           if (!$commits) {
             return null;
           }
 
           $commits[] = $merge_base;
 
           $head_branch_count = null;
           $all_branch_names = ipull($this->getAllBranches(), 'name');
           foreach ($commits as $commit) {
             // Ideally, we would use something like "for-each-ref --contains"
             // to get a filtered list of branches ready for script consumption.
             // Instead, try to get predictable output from "branch --contains".
 
             $flags = array();
             $flags[] = '--no-color';
 
             // NOTE: The "--no-column" flag was introduced in Git 1.7.11, so
             // don't pass it if we're running an older version. See T9953.
             $version = $this->getGitVersion();
             if (version_compare($version, '1.7.11', '>=')) {
               $flags[] = '--no-column';
             }
 
             list($branches) = $this->execxLocal(
               'branch %Ls --contains %s',
               $flags,
               $commit);
             $branches = array_filter(explode("\n", $branches));
 
             // Filter the list, removing the "current" marker (*) and ignoring
             // anything other than known branch names (mainly, any possible
             // "detached HEAD" or "no branch" line).
             foreach ($branches as $key => $branch) {
               $branch = trim($branch, ' *');
               if (in_array($branch, $all_branch_names)) {
                 $branches[$key] = $branch;
               } else {
                 unset($branches[$key]);
               }
             }
 
             if ($head_branch_count === null) {
               // If this is the first commit, it's HEAD. Count how many
               // branches it is on; we want to include commits on the same
               // number of branches. This covers a case where this branch
               // has sub-branches and we're running "arc diff" here again
               // for whatever reason.
               $head_branch_count = count($branches);
             } else if (count($branches) > $head_branch_count) {
               $branches = implode(', ', $branches);
               $this->setBaseCommitExplanation(
                 pht(
                   "it is the first commit between '%s' (the merge-base of ".
                   "'%s' and HEAD) which is also contained by another branch ".
                   "(%s).",
                   $merge_base,
                   $matches[1],
                   $branches));
               return $commit;
             }
           }
         } else {
           list($err) = $this->execManualLocal(
             'cat-file -t %s',
             $name);
           if (!$err) {
             $this->setBaseCommitExplanation(
               pht(
                 "it is specified by '%s' in your %s 'base' configuration.",
                 $rule,
                 $source));
             return $name;
           }
         }
         break;
       case 'arc':
         switch ($name) {
           case 'empty':
             $this->setBaseCommitExplanation(
               pht(
                 "you specified '%s' in your %s 'base' configuration.",
                 $rule,
                 $source));
             return self::GIT_MAGIC_ROOT_COMMIT;
           case 'amended':
             $text = $this->getCommitMessage('HEAD');
             $message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
               $text);
             if ($message->getRevisionID()) {
               $this->setBaseCommitExplanation(
                 pht(
                   "HEAD has been amended with 'Differential Revision:', ".
                   "as specified by '%s' in your %s 'base' configuration.",
                   $rule,
                   $source));
               return 'HEAD^';
             }
             break;
           case 'upstream':
             list($err, $upstream) = $this->execManualLocal(
               'rev-parse --abbrev-ref --symbolic-full-name %s',
               '@{upstream}');
             if (!$err) {
               $upstream = rtrim($upstream);
               list($upstream_merge_base) = $this->execxLocal(
                 'merge-base %s HEAD',
                 $upstream);
               $upstream_merge_base = rtrim($upstream_merge_base);
               $this->setBaseCommitExplanation(
                 pht(
                   "it is the merge-base of the upstream of the current branch ".
                   "and HEAD, and matched the rule '%s' in your %s ".
                   "'base' configuration.",
                   $rule,
                   $source));
               return $upstream_merge_base;
             }
             break;
           case 'this':
             $this->setBaseCommitExplanation(
               pht(
                 "you specified '%s' in your %s 'base' configuration.",
                 $rule,
                 $source));
             return 'HEAD^';
         }
       default:
         return null;
     }
 
     return null;
   }
 
   public function canStashChanges() {
     return true;
   }
 
   public function stashChanges() {
     $this->execxLocal('stash');
     $this->reloadWorkingCopy();
   }
 
   public function unstashChanges() {
     $this->execxLocal('stash pop');
   }
 
   protected function didReloadCommitRange() {
     // After an amend, the symbolic head may resolve to a different commit.
     $this->resolvedHeadCommit = null;
   }
 
   /**
    * Follow the chain of tracking branches upstream until we reach a remote
    * or cycle locally.
    *
    * @param string Ref to start from.
    * @return ArcanistGitUpstreamPath Path to an upstream.
    */
   public function getPathToUpstream($start) {
     $cursor = $start;
     $path = new ArcanistGitUpstreamPath();
     while (true) {
       list($err, $upstream) = $this->execManualLocal(
         'rev-parse --symbolic-full-name %s@{upstream}',
         $cursor);
 
       if ($err) {
         // We ended up somewhere with no tracking branch, so we're done.
         break;
       }
 
       $upstream = trim($upstream);
 
       if (preg_match('(^refs/heads/)', $upstream)) {
         $upstream = preg_replace('(^refs/heads/)', '', $upstream);
 
         $is_cycle = $path->getUpstream($upstream);
 
         $path->addUpstream(
           $cursor,
           array(
             'type' => ArcanistGitUpstreamPath::TYPE_LOCAL,
             'name' => $upstream,
             'cycle' => $is_cycle,
           ));
 
         if ($is_cycle) {
           // We ran into a local cycle, so we're done.
           break;
         }
 
         // We found another local branch, so follow that one upriver.
         $cursor = $upstream;
         continue;
       }
 
       if (preg_match('(^refs/remotes/)', $upstream)) {
         $upstream = preg_replace('(^refs/remotes/)', '', $upstream);
         list($remote, $branch) = explode('/', $upstream, 2);
 
         $path->addUpstream(
           $cursor,
           array(
             'type' => ArcanistGitUpstreamPath::TYPE_REMOTE,
             'name' => $branch,
             'remote' => $remote,
           ));
 
         // We found a remote, so we're done.
         break;
       }
 
       throw new Exception(
         pht(
           'Got unrecognized upstream format ("%s") from Git, expected '.
           '"refs/heads/..." or "refs/remotes/...".',
           $upstream));
     }
 
     return $path;
   }
 
 }
diff --git a/src/repository/api/__tests__/ArcanistRepositoryAPIStateTestCase.php b/src/repository/api/__tests__/ArcanistRepositoryAPIStateTestCase.php
index b6b4c596..ddf703e8 100644
--- a/src/repository/api/__tests__/ArcanistRepositoryAPIStateTestCase.php
+++ b/src/repository/api/__tests__/ArcanistRepositoryAPIStateTestCase.php
@@ -1,189 +1,201 @@
 <?php
 
 final class ArcanistRepositoryAPIStateTestCase extends PhutilTestCase {
 
   public function testGitStateParsing() {
     if (Filesystem::binaryExists('git')) {
       $this->parseState('git_basic.git.tgz');
       $this->parseState('git_submodules_dirty.git.tgz');
       $this->parseState('git_submodules_staged.git.tgz');
+      $this->parseState('git_spaces.git.tgz');
     } else {
       $this->assertSkipped(pht('Git is not installed'));
     }
   }
 
   public function testHgStateParsing() {
     if (Filesystem::binaryExists('hg')) {
       $this->parseState('hg_basic.hg.tgz');
     } else {
       $this->assertSkipped(pht('Mercurial is not installed'));
     }
   }
 
   public function testSvnStateParsing() {
     if (Filesystem::binaryExists('svn')) {
       $this->parseState('svn_basic.svn.tgz');
     } else {
       $this->assertSkipped(pht('Subversion is not installed'));
     }
   }
 
   private function parseState($test) {
     $dir = dirname(__FILE__).'/state/';
     $fixture = PhutilDirectoryFixture::newFromArchive($dir.'/'.$test);
 
     $fixture_path = $fixture->getPath();
     $working_copy = ArcanistWorkingCopyIdentity::newFromPath($fixture_path);
     $configuration_manager = new ArcanistConfigurationManager();
     $configuration_manager->setWorkingCopyIdentity($working_copy);
     $api = ArcanistRepositoryAPI::newAPIFromConfigurationManager(
       $configuration_manager);
 
     $api->setBaseCommitArgumentRules('arc:this');
 
     if ($api instanceof ArcanistSubversionAPI) {
       // Upgrade the repository so that the test will still pass if the local
       // `svn` is newer than the `svn` which created the repository.
 
       // NOTE: Some versions of Subversion (1.7.x?) exit with an error code on
       // a no-op upgrade, although newer versions do not. We just ignore the
       // error here; if it's because of an actual problem we'll hit an error
       // shortly anyway.
       $api->execManualLocal('upgrade');
     }
 
     $this->assertCorrectState($test, $api);
   }
 
   private function assertCorrectState($test, ArcanistRepositoryAPI $api) {
     if ($api instanceof ArcanistGitAPI) {
       $version = $api->getGitVersion();
       if (version_compare($version, '2.11.0', '<')) {
         // Behavior differs slightly on older versions of git; rather than code
         // both variants, skip the tests in the presence of such a git.
         $this->assertSkipped(pht('Behavior differs slightly on git < 2.11.0'));
         return;
       }
     }
 
     $f_mod = ArcanistRepositoryAPI::FLAG_MODIFIED;
     $f_add = ArcanistRepositoryAPI::FLAG_ADDED;
     $f_del = ArcanistRepositoryAPI::FLAG_DELETED;
     $f_unt = ArcanistRepositoryAPI::FLAG_UNTRACKED;
     $f_con = ArcanistRepositoryAPI::FLAG_CONFLICT;
     $f_mis = ArcanistRepositoryAPI::FLAG_MISSING;
     $f_uns = ArcanistRepositoryAPI::FLAG_UNSTAGED;
     $f_unc = ArcanistRepositoryAPI::FLAG_UNCOMMITTED;
     $f_ext = ArcanistRepositoryAPI::FLAG_EXTERNALS;
     $f_obs = ArcanistRepositoryAPI::FLAG_OBSTRUCTED;
     $f_inc = ArcanistRepositoryAPI::FLAG_INCOMPLETE;
 
     switch ($test) {
       case 'svn_basic.svn.tgz':
         $expect_uncommitted = array(
           'ADDED'       => $f_add,
           'COPIED_TO'   => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'MOVED'       => $f_del,
           'MOVED_TO'    => $f_add,
           'PROPCHANGE'  => $f_mod,
           'UNTRACKED'   => $f_unt,
         );
         $this->assertEqual($expect_uncommitted, $api->getUncommittedStatus());
 
         $expect_range = array();
         $this->assertEqual($expect_range, $api->getCommitRangeStatus());
 
         $expect_working = array(
           'ADDED'       => $f_add,
           'COPIED_TO'   => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'MOVED'       => $f_del,
           'MOVED_TO'    => $f_add,
           'PROPCHANGE'  => $f_mod,
           'UNTRACKED'   => $f_unt,
         );
         $this->assertEqual($expect_working, $api->getWorkingCopyStatus());
         break;
       case 'git_basic.git.tgz':
         $expect_uncommitted = array(
           'UNCOMMITTED' => $f_add | $f_unc,
           'UNSTAGED'    => $f_mod | $f_uns | $f_unc,
           'UNTRACKED'   => $f_unt,
         );
 
         $this->assertEqual($expect_uncommitted, $api->getUncommittedStatus());
 
         $expect_range = array(
           'ADDED'       => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'UNSTAGED'    => $f_add,
         );
         $this->assertEqual($expect_range, $api->getCommitRangeStatus());
 
         $expect_working = array(
           'ADDED'       => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'UNCOMMITTED' => $f_add | $f_unc,
           'UNSTAGED'    => $f_add | $f_mod | $f_uns | $f_unc,
           'UNTRACKED'   => $f_unt,
         );
         $this->assertEqual($expect_working, $api->getWorkingCopyStatus());
         break;
       case 'git_submodules_dirty.git.tgz':
         $expect_uncommitted = array(
           '.gitmodules'           => $f_mod | $f_uns | $f_unc,
           'added/'                => $f_unt,
           'deleted'               => $f_del | $f_uns | $f_unc,
           'modified-commit'       => $f_mod | $f_uns | $f_unc,
           'modified-commit-dirty' => $f_ext | $f_mod | $f_uns | $f_unc,
           'modified-dirty'        => $f_ext | $f_mod | $f_uns | $f_unc,
         );
         $this->assertEqual($expect_uncommitted, $api->getUncommittedStatus());
         break;
       case 'git_submodules_staged.git.tgz':
         $expect_uncommitted = array(
           '.gitmodules'           => $f_mod | $f_unc,
           'added'                 => $f_add | $f_unc,
           'deleted'               => $f_del | $f_unc,
           'modified-commit'       => $f_mod | $f_unc,
           'modified-commit-dirty' => $f_ext | $f_mod | $f_uns | $f_unc,
           'modified-dirty'        => $f_ext | $f_mod | $f_uns | $f_unc,
         );
         $this->assertEqual($expect_uncommitted, $api->getUncommittedStatus());
         break;
+      case 'git_spaces.git.tgz':
+        $expect_working = array(
+          'SPACES ADDED'       => $f_add,
+          'SPACES DELETED'     => $f_del,
+          'SPACES MODIFIED'    => $f_mod,
+          'SPACES UNCOMMITTED' => $f_add | $f_unc,
+          'SPACES UNSTAGED'    => $f_add | $f_mod | $f_uns | $f_unc,
+          'SPACES UNTRACKED'   => $f_unt,
+        );
+        $this->assertEqual($expect_working, $api->getWorkingCopyStatus());
+        break;
       case 'hg_basic.hg.tgz':
         $expect_uncommitted = array(
           'UNCOMMITTED' => $f_mod | $f_unc,
           'UNTRACKED'   => $f_unt,
         );
         $this->assertEqual($expect_uncommitted, $api->getUncommittedStatus());
 
         $expect_range = array(
           'ADDED'       => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'UNCOMMITTED' => $f_add,
         );
         $this->assertEqual($expect_range, $api->getCommitRangeStatus());
 
         $expect_working = array(
           'ADDED'       => $f_add,
           'DELETED'     => $f_del,
           'MODIFIED'    => $f_mod,
           'UNCOMMITTED' => $f_add | $f_mod | $f_unc,
           'UNTRACKED'   => $f_unt,
         );
         $this->assertEqual($expect_working, $api->getWorkingCopyStatus());
         break;
       default:
         throw new Exception(
           pht("No test cases for working copy '%s'!", $test));
     }
   }
 
 }
diff --git a/src/repository/api/__tests__/state/git_spaces.git.tgz b/src/repository/api/__tests__/state/git_spaces.git.tgz
new file mode 100644
index 00000000..056fe0d5
Binary files /dev/null and b/src/repository/api/__tests__/state/git_spaces.git.tgz differ
diff --git a/src/workflow/ArcanistDiffWorkflow.php b/src/workflow/ArcanistDiffWorkflow.php
index bae03cec..28b91a3f 100644
--- a/src/workflow/ArcanistDiffWorkflow.php
+++ b/src/workflow/ArcanistDiffWorkflow.php
@@ -1,3002 +1,2986 @@
 <?php
 
 /**
  * Sends changes from your working copy to Differential for code review.
  *
  * @task lintunit   Lint and Unit Tests
  * @task message    Commit and Update Messages
  * @task diffspec   Diff Specification
  * @task diffprop   Diff Properties
  */
 final class ArcanistDiffWorkflow extends ArcanistWorkflow {
 
   private $console;
   private $hasWarnedExternals = false;
   private $unresolvedLint;
   private $excuses = array('lint' => null, 'unit' => null);
   private $testResults;
   private $diffID;
   private $revisionID;
   private $haveUncommittedChanges = false;
   private $diffPropertyFutures = array();
   private $commitMessageFromRevision;
   private $hitAutotargets;
   private $revisionTransactions;
   private $revisionIsDraft;
 
   const STAGING_PUSHED = 'pushed';
   const STAGING_USER_SKIP = 'user.skip';
   const STAGING_DIFF_RAW = 'diff.raw';
   const STAGING_REPOSITORY_UNKNOWN = 'repository.unknown';
   const STAGING_REPOSITORY_UNAVAILABLE = 'repository.unavailable';
   const STAGING_REPOSITORY_UNSUPPORTED = 'repository.unsupported';
   const STAGING_REPOSITORY_UNCONFIGURED = 'repository.unconfigured';
   const STAGING_CLIENT_UNSUPPORTED = 'client.unsupported';
 
   public function getWorkflowName() {
     return 'diff';
   }
 
   public function getCommandSynopses() {
     return phutil_console_format(<<<EOTEXT
       **diff** [__paths__] (svn)
       **diff** [__commit__] (git, hg)
 EOTEXT
       );
   }
 
   public function getCommandHelp() {
     return phutil_console_format(<<<EOTEXT
           Supports: git, svn, hg
           Generate a Differential diff or revision from local changes.
 
           Under git and mercurial, you can specify a commit (like __HEAD^^^__
           or __master__) and Differential will generate a diff against the
           merge base of that commit and your current working directory parent.
 
           Under svn, you can choose to include only some of the modified files
           in the working copy in the diff by specifying their paths. If you
           omit paths, all changes are included in the diff.
 EOTEXT
       );
   }
 
   public function requiresWorkingCopy() {
     return !$this->isRawDiffSource();
   }
 
   public function requiresConduit() {
     return true;
   }
 
   public function requiresAuthentication() {
     return true;
   }
 
   public function requiresRepositoryAPI() {
     if (!$this->isRawDiffSource()) {
       return true;
     }
 
     if ($this->getArgument('use-commit-message')) {
       return true;
     }
 
     return false;
   }
 
   public function getDiffID() {
     return $this->diffID;
   }
 
   public function getArguments() {
     $arguments = array(
       'message' => array(
         'short'       => 'm',
         'param'       => 'message',
         'help' => pht(
           'When updating a revision, use the specified message instead of '.
           'prompting.'),
       ),
       'message-file' => array(
         'short' => 'F',
         'param' => 'file',
         'paramtype' => 'file',
         'help' => pht(
           'When creating a revision, read revision information '.
           'from this file.'),
       ),
       'use-commit-message' => array(
         'supports' => array(
           'git',
           // TODO: Support mercurial.
         ),
         'short' => 'C',
         'param' => 'commit',
         'help' => pht('Read revision information from a specific commit.'),
         'conflicts' => array(
           'only' => null,
           'update'  => null,
         ),
       ),
       'edit' => array(
         'supports'    => array(
           'git',
           'hg',
         ),
         'nosupport'   => array(
           'svn' => pht('Edit revisions via the web interface when using SVN.'),
         ),
         'help' => pht(
           'When updating a revision under git, edit revision information '.
           'before updating.'),
       ),
       'raw' => array(
         'help' => pht(
           'Read diff from stdin, not from the working copy. This disables '.
           'many Arcanist/Phabricator features which depend on having access '.
           'to the working copy.'),
         'conflicts' => array(
           'less-context'        => null,
           'apply-patches'       => pht('%s disables lint.', '--raw'),
           'never-apply-patches' => pht('%s disables lint.', '--raw'),
           'advice'              => pht('%s disables lint.', '--raw'),
           'lintall'             => pht('%s disables lint.', '--raw'),
 
           'create'              => pht(
             '%s and %s both need stdin. Use %s.',
             '--raw',
             '--create',
             '--raw-command'),
           'edit'                => pht(
             '%s and %s both need stdin. Use %s.',
             '--raw',
             '--edit',
             '--raw-command'),
           'raw-command'         => null,
         ),
       ),
       'raw-command' => array(
         'param' => 'command',
         'help' => pht(
           'Generate diff by executing a specified command, not from the '.
           'working copy. This disables many Arcanist/Phabricator features '.
           'which depend on having access to the working copy.'),
         'conflicts' => array(
           'less-context'        => null,
           'apply-patches'       => pht('%s disables lint.', '--raw-command'),
           'never-apply-patches' => pht('%s disables lint.', '--raw-command'),
           'advice'              => pht('%s disables lint.', '--raw-command'),
           'lintall'             => pht('%s disables lint.', '--raw-command'),
         ),
       ),
       'create' => array(
         'help' => pht('Always create a new revision.'),
         'conflicts' => array(
           'edit'    => pht(
             '%s can not be used with %s.',
             '--create',
             '--edit'),
           'only' => pht(
             '%s can not be used with %s.',
             '--create',
             '--only'),
           'update'  => pht(
             '%s can not be used with %s.',
             '--create',
             '--update'),
         ),
       ),
       'update' => array(
         'param' => 'revision_id',
         'help'  => pht('Always update a specific revision.'),
       ),
       'draft' => array(
         'help' => pht(
           'Create a draft revision so you can look over your changes before '.
           'involving anyone else. Other users will not be notified about the '.
           'revision until you later use "Request Review" to publish it. You '.
           'can still share the draft by giving someone the link.'),
         'conflicts' => array(
           'edit' => null,
           'only' => null,
           'update' => null,
         ),
       ),
       'nounit' => array(
         'help' => pht('Do not run unit tests.'),
       ),
       'nolint' => array(
         'help' => pht('Do not run lint.'),
         'conflicts' => array(
           'lintall'   => pht('%s suppresses lint.', '--nolint'),
           'advice'    => pht('%s suppresses lint.', '--nolint'),
           'apply-patches' => pht('%s suppresses lint.', '--nolint'),
           'never-apply-patches' => pht('%s suppresses lint.', '--nolint'),
         ),
       ),
       'only' => array(
         'help' => pht(
           'Instead of creating or updating a revision, only create a diff, '.
           'which you may later attach to a revision.'),
         'conflicts' => array(
           'edit'      => pht('%s does affect revisions.', '--only'),
           'message'   => pht('%s does not update any revision.', '--only'),
         ),
       ),
       'encoding' => array(
         'param' => 'encoding',
         'help' => pht(
           'Attempt to convert non UTF-8 hunks into specified encoding.'),
       ),
       'allow-untracked' => array(
         'help' => pht('Skip checks for untracked files in the working copy.'),
       ),
       'excuse' => array(
         'param' => 'excuse',
         'help' => pht(
           'Provide a prepared in advance excuse for any lints/tests '.
           'shall they fail.'),
       ),
       'less-context' => array(
         'help' => pht(
           "Normally, files are diffed with full context: the entire file is ".
           "sent to Differential so reviewers can 'show more' and see it. If ".
           "you are making changes to very large files with tens of thousands ".
           "of lines, this may not work well. With this flag, a diff will ".
           "be created that has only a few lines of context."),
       ),
       'lintall' => array(
         'help' => pht(
           'Raise all lint warnings, not just those on lines you changed.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'advice' => array(
         'help' => pht(
           'Require excuse for lint advice in addition to lint warnings and '.
           'errors.'),
       ),
       'only-new' => array(
         'param' => 'bool',
         'help' => pht(
           'Display only lint messages not present in the original code.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'apply-patches' => array(
         'help' => pht(
           'Apply patches suggested by lint to the working copy without '.
           'prompting.'),
         'conflicts' => array(
           'never-apply-patches' => true,
         ),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'never-apply-patches' => array(
         'help' => pht('Never apply patches suggested by lint.'),
         'conflicts' => array(
           'apply-patches' => true,
         ),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'amend-all' => array(
         'help' => pht(
           'When linting git repositories, amend HEAD with all patches '.
           'suggested by lint without prompting.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'amend-autofixes' => array(
         'help' => pht(
           'When linting git repositories, amend HEAD with autofix '.
           'patches suggested by lint without prompting.'),
         'passthru' => array(
           'lint' => true,
         ),
       ),
       'add-all' => array(
         'short' => 'a',
         'help' => pht(
           'Automatically add all unstaged and uncommitted '.
           'files to the commit.'),
       ),
       'json' => array(
         'help' => pht(
           'Emit machine-readable JSON. EXPERIMENTAL! Probably does not work!'),
       ),
       'no-amend' => array(
         'help' => pht(
           'Never amend commits in the working copy with lint patches.'),
       ),
       'uncommitted' => array(
         'help' => pht('Suppress warning about uncommitted changes.'),
         'supports' => array(
           'hg',
         ),
       ),
       'verbatim' => array(
         'help' => pht(
           'When creating a revision, try to use the working copy commit '.
           'message verbatim, without prompting to edit it. When updating a '.
           'revision, update some fields from the local commit message.'),
         'supports' => array(
           'hg',
           'git',
         ),
         'conflicts' => array(
           'use-commit-message'  => true,
           'update'              => true,
           'only' => true,
           'raw'                 => true,
           'raw-command'         => true,
           'message-file'        => true,
         ),
       ),
       'reviewers' => array(
         'param' => 'usernames',
         'help' => pht('When creating a revision, add reviewers.'),
         'conflicts' => array(
           'only' => true,
           'update'  => true,
         ),
       ),
       'cc' => array(
         'param' => 'usernames',
         'help' => pht('When creating a revision, add CCs.'),
         'conflicts' => array(
           'only' => true,
           'update'  => true,
         ),
       ),
       'skip-binaries' => array(
         'help'  => pht('Do not upload binaries (like images).'),
       ),
       'skip-staging' => array(
         'help' => pht('Do not copy changes to the staging area.'),
       ),
       'ignore-unsound-tests' => array(
         'help'  => pht('Ignore unsound test failures without prompting.'),
       ),
       'base' => array(
         'param' => 'rules',
         'help'  => pht('Additional rules for determining base revision.'),
         'nosupport' => array(
           'svn' => pht('Subversion does not use base commits.'),
         ),
         'supports' => array('git', 'hg'),
       ),
       'coverage' => array(
         'help' => pht('Always enable coverage information.'),
         'conflicts' => array(
           'no-coverage' => null,
         ),
         'passthru' => array(
           'unit' => true,
         ),
       ),
       'no-coverage' => array(
         'help' => pht('Always disable coverage information.'),
         'passthru' => array(
           'unit' => true,
         ),
       ),
       'browse' => array(
         'help' => pht(
           'After creating a diff or revision, open it in a web browser.'),
       ),
       '*' => 'paths',
       'head' => array(
         'param' => 'commit',
         'help' => pht(
           'Specify the end of the commit range. This disables many '.
           'Arcanist/Phabricator features which depend on having access to '.
           'the working copy.'),
         'supports' => array('git'),
         'nosupport' => array(
           'svn' => pht('Subversion does not support commit ranges.'),
           'hg' => pht('Mercurial does not support %s yet.', '--head'),
         ),
         'conflicts' => array(
           'lintall'   => pht('%s suppresses lint.', '--head'),
           'advice'    => pht('%s suppresses lint.', '--head'),
         ),
       ),
     );
 
     return $arguments;
   }
 
   public function isRawDiffSource() {
     return $this->getArgument('raw') || $this->getArgument('raw-command');
   }
 
   public function run() {
     $this->console = PhutilConsole::getConsole();
 
     $this->runRepositoryAPISetup();
     $this->runDiffSetupBasics();
 
     $commit_message = $this->buildCommitMessage();
 
     $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_DIDBUILDMESSAGE,
       array(
         'message' => $commit_message,
       ));
 
     if (!$this->shouldOnlyCreateDiff()) {
       $revision = $this->buildRevisionFromCommitMessage($commit_message);
     }
 
     $server = $this->console->getServer();
     $server->setHandler(array($this, 'handleServerMessage'));
     $data = $this->runLintUnit();
 
     $lint_result = $data['lintResult'];
     $this->unresolvedLint = $data['unresolvedLint'];
     $unit_result = $data['unitResult'];
     $this->testResults = $data['testResults'];
 
     if ($this->getArgument('nolint')) {
       $this->excuses['lint'] = $this->getSkipExcuse(
         pht('Provide explanation for skipping lint or press Enter to abort:'),
         'lint-excuses');
     }
 
     if ($this->getArgument('nounit')) {
       $this->excuses['unit'] = $this->getSkipExcuse(
         pht(
           'Provide explanation for skipping unit tests '.
           'or press Enter to abort:'),
         'unit-excuses');
     }
 
     $changes = $this->generateChanges();
     if (!$changes) {
       throw new ArcanistUsageException(
         pht('There are no changes to generate a diff from!'));
     }
 
     $diff_spec = array(
       'changes' => mpull($changes, 'toDictionary'),
       'lintStatus' => $this->getLintStatus($lint_result),
       'unitStatus' => $this->getUnitStatus($unit_result),
     ) + $this->buildDiffSpecification();
 
     $conduit = $this->getConduit();
     $diff_info = $conduit->callMethodSynchronous(
       'differential.creatediff',
       $diff_spec);
 
     $this->diffID = $diff_info['diffid'];
 
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_WASCREATED,
       array(
         'diffID' => $diff_info['diffid'],
         'lintResult' => $lint_result,
         'unitResult' => $unit_result,
       ));
 
     $this->submitChangesToStagingArea($this->diffID);
 
     $phid = idx($diff_info, 'phid');
     if ($phid) {
       $this->hitAutotargets = $this->updateAutotargets(
         $phid,
         $unit_result);
     }
 
     $this->updateLintDiffProperty();
     $this->updateUnitDiffProperty();
     $this->updateLocalDiffProperty();
     $this->updateOntoDiffProperty();
     $this->resolveDiffPropertyUpdates();
 
     $output_json = $this->getArgument('json');
 
     if ($this->shouldOnlyCreateDiff()) {
       if (!$output_json) {
         echo phutil_console_format(
           "%s\n        **%s** __%s__\n\n",
           pht('Created a new Differential diff:'),
           pht('Diff URI:'),
           $diff_info['uri']);
       } else {
         $human = ob_get_clean();
         echo json_encode(array(
           'diffURI' => $diff_info['uri'],
           'diffID'  => $this->getDiffID(),
           'human'   => $human,
         ))."\n";
         ob_start();
       }
 
       if ($this->shouldOpenCreatedObjectsInBrowser()) {
         $this->openURIsInBrowser(array($diff_info['uri']));
       }
     } else {
       $is_draft = $this->getArgument('draft');
       $revision['diffid'] = $this->getDiffID();
 
       if ($commit_message->getRevisionID()) {
         if ($is_draft) {
           // TODO: In at least some cases, we could raise this earlier in the
           // workflow to save users some time before the workflow aborts.
           if ($this->revisionIsDraft) {
             $this->writeWarn(
               pht('ALREADY A DRAFT'),
               pht(
                 'You are updating a revision ("%s") with the "--draft" flag, '.
                 'but this revision is already a draft. You only need to '.
                 'provide the "--draft" flag when creating a revision. Draft '.
                 'revisions are not published until you explicitly request '.
                 'review from the web UI.',
                 $commit_message->getRevisionMonogram()));
           } else {
             throw new ArcanistUsageException(
               pht(
                 'You are updating a revision ("%s") with the "--draft" flag, '.
                 'but this revision has already been published for review. '.
                 'You can not turn a revision back into a draft once it has '.
                 'been published.',
                 $commit_message->getRevisionMonogram()));
           }
         }
 
         $result = $conduit->callMethodSynchronous(
           'differential.updaterevision',
           $revision);
 
         foreach (array('edit-messages.json', 'update-messages.json') as $file) {
           $messages = $this->readScratchJSONFile($file);
           unset($messages[$revision['id']]);
           $this->writeScratchJSONFile($file, $messages);
         }
 
         $result_uri = $result['uri'];
         $result_id = $result['revisionid'];
 
         echo pht('Updated an existing Differential revision:')."\n";
       } else {
         // NOTE: We're either using "differential.revision.edit" (preferred)
         // if we can, or falling back to "differential.createrevision"
         // (the older way) if not.
 
         $xactions = $this->revisionTransactions;
         if ($xactions) {
           $xactions[] = array(
             'type' => 'update',
             'value' => $diff_info['phid'],
           );
 
           if ($is_draft) {
             $xactions[] = array(
               'type' => 'draft',
               'value' => true,
             );
           }
 
           $result = $conduit->callMethodSynchronous(
             'differential.revision.edit',
             array(
               'transactions' => $xactions,
             ));
 
           $result_id = idxv($result, array('object', 'id'));
           if (!$result_id) {
             throw new Exception(
               pht(
                 'Expected a revision ID to be returned by '.
                 '"differential.revision.edit".'));
           }
 
           // TODO: This is hacky, but we don't currently receive a URI back
           // from "differential.revision.edit".
           $result_uri = id(new PhutilURI($this->getConduitURI()))
             ->setPath('/D'.$result_id);
         } else {
           if ($is_draft) {
             throw new ArcanistUsageException(
               pht(
                 'You have specified "--draft", but the version of Phabricator '.
                 'on the server is too old to support draft revisions. Omit '.
                 'the flag or upgrade the server software.'));
           }
 
           $revision = $this->dispatchWillCreateRevisionEvent($revision);
 
           $result = $conduit->callMethodSynchronous(
             'differential.createrevision',
             $revision);
 
           $result_uri = $result['uri'];
           $result_id = $result['revisionid'];
         }
 
         $revised_message = $conduit->callMethodSynchronous(
           'differential.getcommitmessage',
           array(
             'revision_id' => $result_id,
           ));
 
         if ($this->shouldAmend()) {
           $repository_api = $this->getRepositoryAPI();
           if ($repository_api->supportsAmend()) {
             echo pht('Updating commit message...')."\n";
             $repository_api->amendCommit($revised_message);
           } else {
             echo pht(
               'Commit message was not amended. Amending commit message is '.
               'only supported in git and hg (version 2.2 or newer)');
           }
         }
 
         echo pht('Created a new Differential revision:')."\n";
       }
 
       $uri = $result_uri;
       echo phutil_console_format(
         "        **%s** __%s__\n\n",
         pht('Revision URI:'),
         $uri);
 
       if ($this->shouldOpenCreatedObjectsInBrowser()) {
         $this->openURIsInBrowser(array($uri));
       }
     }
 
     echo pht('Included changes:')."\n";
     foreach ($changes as $change) {
       echo '  '.$change->renderTextSummary()."\n";
     }
 
     if ($output_json) {
       ob_get_clean();
     }
 
     $this->removeScratchFile('create-message');
 
     return 0;
   }
 
   private function runRepositoryAPISetup() {
     if (!$this->requiresRepositoryAPI()) {
       return;
     }
 
     $repository_api = $this->getRepositoryAPI();
     if ($this->getArgument('less-context')) {
       $repository_api->setDiffLinesOfContext(3);
     }
 
     $repository_api->setBaseCommitArgumentRules(
       $this->getArgument('base', ''));
 
     if ($repository_api->supportsCommitRanges()) {
       $this->parseBaseCommitArgument($this->getArgument('paths'));
     }
 
     $head_commit = $this->getArgument('head');
     if ($head_commit !== null) {
       $repository_api->setHeadCommit($head_commit);
     }
 
   }
 
   private function runDiffSetupBasics() {
     $output_json = $this->getArgument('json');
     if ($output_json) {
       // TODO: We should move this to a higher-level and put an indirection
       // layer between echoing stuff and stdout.
       ob_start();
     }
 
     if ($this->requiresWorkingCopy()) {
       $repository_api = $this->getRepositoryAPI();
       if ($this->getArgument('add-all')) {
         $this->setCommitMode(self::COMMIT_ENABLE);
       } else if ($this->getArgument('uncommitted')) {
         $this->setCommitMode(self::COMMIT_DISABLE);
       } else {
         $this->setCommitMode(self::COMMIT_ALLOW);
       }
       if ($repository_api instanceof ArcanistSubversionAPI) {
         $repository_api->limitStatusToPaths($this->getArgument('paths'));
       }
       if (!$this->getArgument('head')) {
         $this->requireCleanWorkingCopy();
       }
     }
 
     $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_DIDCOLLECTCHANGES,
       array());
   }
 
   private function buildRevisionFromCommitMessage(
     ArcanistDifferentialCommitMessage $message) {
 
     $conduit = $this->getConduit();
 
     $revision_id = $message->getRevisionID();
     $revision = array(
       'fields' => $message->getFields(),
     );
     $xactions = $message->getTransactions();
 
     if ($revision_id) {
 
       // With '--verbatim', pass the (possibly modified) local fields. This
       // allows the user to edit some fields (like "title" and "summary")
       // locally without '--edit' and have changes automatically synchronized.
       // Without '--verbatim', we do not update the revision to reflect local
       // commit message changes.
       if ($this->getArgument('verbatim')) {
         $use_fields = $message->getFields();
       } else {
         $use_fields = array();
       }
 
       $should_edit = $this->getArgument('edit');
       $edit_messages = $this->readScratchJSONFile('edit-messages.json');
       $remote_corpus = idx($edit_messages, $revision_id);
 
       if (!$should_edit || !$remote_corpus || $use_fields) {
         if ($this->commitMessageFromRevision) {
           $remote_corpus = $this->commitMessageFromRevision;
         } else {
           $remote_corpus = $conduit->callMethodSynchronous(
             'differential.getcommitmessage',
             array(
               'revision_id' => $revision_id,
               'edit'        => 'edit',
               'fields'      => $use_fields,
             ));
         }
       }
 
       if ($should_edit) {
         $edited = $this->newInteractiveEditor($remote_corpus)
           ->setName('differential-edit-revision-info')
           ->editInteractively();
         if ($edited != $remote_corpus) {
           $remote_corpus = $edited;
           $edit_messages[$revision_id] = $remote_corpus;
           $this->writeScratchJSONFile('edit-messages.json', $edit_messages);
         }
       }
 
       if ($this->commitMessageFromRevision == $remote_corpus) {
         $new_message = $message;
       } else {
         $remote_corpus = ArcanistCommentRemover::removeComments(
           $remote_corpus);
         $new_message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $remote_corpus);
         $new_message->pullDataFromConduit($conduit);
       }
 
       $revision['fields'] = $new_message->getFields();
       $xactions = $new_message->getTransactions();
 
       $revision['id'] = $revision_id;
       $this->revisionID = $revision_id;
 
       $revision['message'] = $this->getArgument('message');
       if (!strlen($revision['message'])) {
         $update_messages = $this->readScratchJSONFile('update-messages.json');
 
         $update_messages[$revision_id] = $this->getUpdateMessage(
           $revision['fields'],
           idx($update_messages, $revision_id));
 
         $revision['message'] = ArcanistCommentRemover::removeComments(
           $update_messages[$revision_id]);
         if (!strlen(trim($revision['message']))) {
           throw new ArcanistUserAbortException();
         }
 
         $this->writeScratchJSONFile('update-messages.json', $update_messages);
       }
     }
 
     $this->revisionTransactions = $xactions;
 
     return $revision;
   }
 
   protected function shouldOnlyCreateDiff() {
     if ($this->getArgument('create')) {
       return false;
     }
 
     if ($this->getArgument('update')) {
       return false;
     }
 
     if ($this->getArgument('use-commit-message')) {
       return false;
     }
 
     if ($this->isRawDiffSource()) {
       return true;
     }
 
     return $this->getArgument('only');
   }
 
   private function generateAffectedPaths() {
     if ($this->isRawDiffSource()) {
       return array();
     }
 
     $repository_api = $this->getRepositoryAPI();
     if ($repository_api instanceof ArcanistSubversionAPI) {
       $file_list = new FileList($this->getArgument('paths', array()));
       $paths = $repository_api->getSVNStatus($externals = true);
       foreach ($paths as $path => $mask) {
         if (!$file_list->contains($repository_api->getPath($path), true)) {
           unset($paths[$path]);
         }
       }
 
       $warn_externals = array();
       foreach ($paths as $path => $mask) {
         $any_mod = ($mask & ArcanistRepositoryAPI::FLAG_ADDED) ||
                    ($mask & ArcanistRepositoryAPI::FLAG_MODIFIED) ||
                    ($mask & ArcanistRepositoryAPI::FLAG_DELETED);
         if ($mask & ArcanistRepositoryAPI::FLAG_EXTERNALS) {
           unset($paths[$path]);
           if ($any_mod) {
             $warn_externals[] = $path;
           }
         }
       }
 
       if ($warn_externals && !$this->hasWarnedExternals) {
         echo phutil_console_format(
           "%s\n\n%s\n\n",
           pht(
             "The working copy includes changes to '%s' paths. These ".
             "changes will not be included in the diff because SVN can not ".
             "commit 'svn:externals' changes alongside normal changes.",
             'svn:externals'),
           pht(
             "Modified '%s' files:",
             'svn:externals'),
           phutil_console_wrap(implode("\n", $warn_externals), 8));
         $prompt = pht('Generate a diff (with just local changes) anyway?');
         if (!phutil_console_confirm($prompt)) {
           throw new ArcanistUserAbortException();
         } else {
           $this->hasWarnedExternals = true;
         }
       }
 
     } else {
       $paths = $repository_api->getWorkingCopyStatus();
     }
 
     foreach ($paths as $path => $mask) {
       if ($mask & ArcanistRepositoryAPI::FLAG_UNTRACKED) {
         unset($paths[$path]);
       }
     }
 
     return $paths;
   }
 
 
   protected function generateChanges() {
     $parser = $this->newDiffParser();
 
     $is_raw = $this->isRawDiffSource();
     if ($is_raw) {
 
       if ($this->getArgument('raw')) {
         fwrite(STDERR, pht('Reading diff from stdin...')."\n");
         $raw_diff = file_get_contents('php://stdin');
       } else if ($this->getArgument('raw-command')) {
         list($raw_diff) = execx('%C', $this->getArgument('raw-command'));
       } else {
         throw new Exception(pht('Unknown raw diff source.'));
       }
 
       $changes = $parser->parseDiff($raw_diff);
       foreach ($changes as $key => $change) {
         // Remove "message" changes, e.g. from "git show".
         if ($change->getType() == ArcanistDiffChangeType::TYPE_MESSAGE) {
           unset($changes[$key]);
         }
       }
       return $changes;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     if ($repository_api instanceof ArcanistSubversionAPI) {
       $paths = $this->generateAffectedPaths();
       $this->primeSubversionWorkingCopyData($paths);
 
       // Check to make sure the user is diffing from a consistent base revision.
       // This is mostly just an abuse sanity check because it's silly to do this
       // and makes the code more difficult to effectively review, but it also
       // affects patches and makes them nonportable.
       $bases = $repository_api->getSVNBaseRevisions();
 
       // Remove all files with baserev "0"; these files are new.
       foreach ($bases as $path => $baserev) {
         if ($bases[$path] <= 0) {
           unset($bases[$path]);
         }
       }
 
       if ($bases) {
         $rev = reset($bases);
 
         $revlist = array();
         foreach ($bases as $path => $baserev) {
           $revlist[] = '    '.pht('Revision %s, %s', $baserev, $path);
         }
         $revlist = implode("\n", $revlist);
 
         foreach ($bases as $path => $baserev) {
           if ($baserev !== $rev) {
             throw new ArcanistUsageException(
               pht(
                 "Base revisions of changed paths are mismatched. Update all ".
                 "paths to the same base revision before creating a diff: ".
                 "\n\n%s",
                 $revlist));
           }
         }
 
         // If you have a change which affects several files, all of which are
         // at a consistent base revision, treat that revision as the effective
         // base revision. The use case here is that you made a change to some
         // file, which updates it to HEAD, but want to be able to change it
         // again without updating the entire working copy. This is a little
         // sketchy but it arises in Facebook Ops workflows with config files and
         // doesn't have any real material tradeoffs (e.g., these patches are
         // perfectly applyable).
         $repository_api->overrideSVNBaseRevisionNumber($rev);
       }
 
       $changes = $parser->parseSubversionDiff(
         $repository_api,
         $paths);
     } else if ($repository_api instanceof ArcanistGitAPI) {
       $diff = $repository_api->getFullGitDiff(
         $repository_api->getBaseCommit(),
         $repository_api->getHeadCommit());
       if (!strlen($diff)) {
         throw new ArcanistUsageException(
           pht('No changes found. (Did you specify the wrong commit range?)'));
       }
       $changes = $parser->parseDiff($diff);
     } else if ($repository_api instanceof ArcanistMercurialAPI) {
       $diff = $repository_api->getFullMercurialDiff();
       if (!strlen($diff)) {
         throw new ArcanistUsageException(
           pht('No changes found. (Did you specify the wrong commit range?)'));
       }
       $changes = $parser->parseDiff($diff);
     } else {
       throw new Exception(pht('Repository API is not supported.'));
     }
 
-    if (count($changes) > 250) {
-      $message = pht(
-        'This diff has a very large number of changes (%s). Differential '.
-        'works best for changes which will receive detailed human review, '.
-        'and not as well for large automated changes or bulk checkins. '.
-        'See %s for information about reviewing big checkins. Continue anyway?',
-        phutil_count($changes),
-        'https://secure.phabricator.com/book/phabricator/article/'.
-          'differential_large_changes/');
-
-      if (!phutil_console_confirm($message)) {
-        throw new ArcanistUsageException(
-          pht('Aborted generation of gigantic diff.'));
-      }
-    }
-
     $limit = 1024 * 1024 * 4;
     foreach ($changes as $change) {
       $size = 0;
       foreach ($change->getHunks() as $hunk) {
         $size += strlen($hunk->getCorpus());
       }
       if ($size > $limit) {
         $byte_warning = pht(
           "Diff for '%s' with context is %s bytes in length. ".
           "Generally, source changes should not be this large.",
           $change->getCurrentPath(),
           new PhutilNumber($size));
         if (!$this->getArgument('less-context')) {
           $byte_warning .= ' '.pht(
             "If this file is a huge text file, try using the '%s' flag.",
             '--less-context');
         }
         if ($repository_api instanceof ArcanistSubversionAPI) {
           throw new ArcanistUsageException(
             $byte_warning.' '.
             pht(
               "If the file is not a text file, mark it as binary with:".
               "\n\n  $ %s\n",
               'svn propset svn:mime-type application/octet-stream <filename>'));
         } else {
           $confirm = $byte_warning.' '.pht(
             "If the file is not a text file, you can mark it 'binary'. ".
             "Mark this file as 'binary' and continue?");
           if (phutil_console_confirm($confirm)) {
             $change->convertToBinaryChange($repository_api);
           } else {
             throw new ArcanistUsageException(
               pht('Aborted generation of gigantic diff.'));
           }
         }
       }
     }
 
     $try_encoding = nonempty($this->getArgument('encoding'), null);
 
     $utf8_problems = array();
     foreach ($changes as $change) {
       foreach ($change->getHunks() as $hunk) {
         $corpus = $hunk->getCorpus();
         if (!phutil_is_utf8($corpus)) {
 
           // If this corpus is heuristically binary, don't try to convert it.
           // mb_check_encoding() and mb_convert_encoding() are both very very
           // liberal about what they're willing to process.
           $is_binary = ArcanistDiffUtils::isHeuristicBinaryFile($corpus);
           if (!$is_binary) {
 
             if (!$try_encoding) {
               try {
                 $try_encoding = $this->getRepositoryEncoding();
               } catch (ConduitClientException $e) {
                 if ($e->getErrorCode() == 'ERR-BAD-ARCANIST-PROJECT') {
                   echo phutil_console_wrap(
                     pht('Lookup of encoding in arcanist project failed: %s',
                         $e->getMessage())."\n");
                 } else {
                   throw $e;
                 }
               }
             }
 
             if ($try_encoding) {
               $corpus = phutil_utf8_convert($corpus, 'UTF-8', $try_encoding);
               $name = $change->getCurrentPath();
               if (phutil_is_utf8($corpus)) {
                 $this->writeStatusMessage(
                   pht(
                     "Converted a '%s' hunk from '%s' to UTF-8.\n",
                     $name,
                     $try_encoding));
                 $hunk->setCorpus($corpus);
                 continue;
               }
             }
           }
           $utf8_problems[] = $change;
           break;
         }
       }
     }
 
     // If there are non-binary files which aren't valid UTF-8, warn the user
     // and treat them as binary changes. See D327 for discussion of why Arcanist
     // has this behavior.
     if ($utf8_problems) {
       $utf8_warning =
         sprintf(
           "%s\n\n%s\n\n    %s\n",
           pht(
             'This diff includes %s file(s) which are not valid UTF-8 (they '.
             'contain invalid byte sequences). You can either stop this '.
             'workflow and fix these files, or continue. If you continue, '.
             'these files will be marked as binary.',
             phutil_count($utf8_problems)),
           pht(
             "You can learn more about how Phabricator handles character ".
             "encodings (and how to configure encoding settings and detect and ".
             "correct encoding problems) by reading 'User Guide: UTF-8 and ".
             "Character Encoding' in the Phabricator documentation."),
           pht(
             '%s AFFECTED FILE(S)',
             phutil_count($utf8_problems)));
       $confirm = pht(
         'Do you want to mark these %s file(s) as binary and continue?',
         phutil_count($utf8_problems));
 
       echo phutil_console_format(
         "**%s**\n",
         pht('Invalid Content Encoding (Non-UTF8)'));
       echo phutil_console_wrap($utf8_warning);
 
       $file_list = mpull($utf8_problems, 'getCurrentPath');
       $file_list = '    '.implode("\n    ", $file_list);
       echo $file_list;
 
       if (!phutil_console_confirm($confirm, $default_no = false)) {
         throw new ArcanistUsageException(pht('Aborted workflow to fix UTF-8.'));
       } else {
         foreach ($utf8_problems as $change) {
           $change->convertToBinaryChange($repository_api);
         }
       }
     }
 
     $this->uploadFilesForChanges($changes);
 
     return $changes;
   }
 
   private function getGitParentLogInfo() {
     $info = array(
       'parent'        => null,
       'base_revision' => null,
       'base_path'     => null,
       'uuid'          => null,
     );
 
     $repository_api = $this->getRepositoryAPI();
 
     $parser = $this->newDiffParser();
     $history_messages = $repository_api->getGitHistoryLog();
     if (!$history_messages) {
       // This can occur on the initial commit.
       return $info;
     }
     $history_messages = $parser->parseDiff($history_messages);
 
     foreach ($history_messages as $key => $change) {
       try {
         $message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $change->getMetadata('message'));
         if ($message->getRevisionID() && $info['parent'] === null) {
           $info['parent'] = $message->getRevisionID();
         }
         if ($message->getGitSVNBaseRevision() &&
             $info['base_revision'] === null) {
           $info['base_revision'] = $message->getGitSVNBaseRevision();
           $info['base_path']     = $message->getGitSVNBasePath();
         }
         if ($message->getGitSVNUUID()) {
           $info['uuid'] = $message->getGitSVNUUID();
         }
         if ($info['parent'] && $info['base_revision']) {
           break;
         }
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         // Ignore.
       } catch (ArcanistUsageException $ex) {
         // Ignore an invalid Differential Revision field in the parent commit
       }
     }
 
     return $info;
   }
 
   protected function primeSubversionWorkingCopyData($paths) {
     $repository_api = $this->getRepositoryAPI();
 
     $futures = array();
     $targets = array();
     foreach ($paths as $path => $mask) {
       $futures[] = $repository_api->buildDiffFuture($path);
       $targets[] = array('command' => 'diff', 'path' => $path);
       $futures[] = $repository_api->buildInfoFuture($path);
       $targets[] = array('command' => 'info', 'path' => $path);
     }
 
     $futures = id(new FutureIterator($futures))
       ->limit(8);
     foreach ($futures as $key => $future) {
       $target = $targets[$key];
       if ($target['command'] == 'diff') {
         $repository_api->primeSVNDiffResult(
           $target['path'],
           $future->resolve());
       } else {
         $repository_api->primeSVNInfoResult(
           $target['path'],
           $future->resolve());
       }
     }
   }
 
   private function shouldAmend() {
     if ($this->isRawDiffSource()) {
       return false;
     }
 
     if ($this->haveUncommittedChanges) {
       return false;
     }
 
     if ($this->getArgument('no-amend')) {
       return false;
     }
 
     if ($this->getArgument('head') !== null) {
       return false;
     }
 
     // Run this last: with --raw or --raw-command, we won't have a repository
     // API.
     if ($this->isHistoryImmutable()) {
       return false;
     }
 
     return true;
   }
 
 
 /* -(  Lint and Unit Tests  )------------------------------------------------ */
 
 
   /**
    * @task lintunit
    */
   private function runLintUnit() {
     $lint_result = $this->runLint();
     $unit_result = $this->runUnit();
     return array(
       'lintResult' => $lint_result,
       'unresolvedLint' => $this->unresolvedLint,
       'unitResult' => $unit_result,
       'testResults' => $this->testResults,
     );
   }
 
 
   /**
    * @task lintunit
    */
   private function runLint() {
     if ($this->getArgument('nolint') ||
         $this->isRawDiffSource() ||
         $this->getArgument('head')) {
       return ArcanistLintWorkflow::RESULT_SKIP;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     $this->console->writeOut("%s\n", pht('Linting...'));
     try {
       $argv = $this->getPassthruArgumentsAsArgv('lint');
       if ($repository_api->supportsCommitRanges()) {
         $argv[] = '--rev';
         $argv[] = $repository_api->getBaseCommit();
       }
 
       $lint_workflow = $this->buildChildWorkflow('lint', $argv);
 
       if ($this->shouldAmend()) {
         // TODO: We should offer to create a checkpoint commit.
         $lint_workflow->setShouldAmendChanges(true);
       }
 
       $lint_result = $lint_workflow->run();
 
       switch ($lint_result) {
         case ArcanistLintWorkflow::RESULT_OKAY:
           if ($this->getArgument('advice') &&
               $lint_workflow->getUnresolvedMessages()) {
             $this->getErrorExcuse(
               'lint',
               pht('Lint issued unresolved advice.'),
               'lint-excuses');
           } else {
             $this->console->writeOut(
               "<bg:green>** %s **</bg> %s\n",
               pht('LINT OKAY'),
               pht('No lint problems.'));
           }
           break;
         case ArcanistLintWorkflow::RESULT_WARNINGS:
           $this->getErrorExcuse(
             'lint',
             pht('Lint issued unresolved warnings.'),
             'lint-excuses');
           break;
         case ArcanistLintWorkflow::RESULT_ERRORS:
           $this->console->writeOut(
             "<bg:red>** %s **</bg> %s\n",
             pht('LINT ERRORS'),
             pht('Lint raised errors!'));
           $this->getErrorExcuse(
             'lint',
             pht('Lint issued unresolved errors!'),
             'lint-excuses');
           break;
       }
 
       $this->unresolvedLint = array();
       foreach ($lint_workflow->getUnresolvedMessages() as $message) {
         $this->unresolvedLint[] = $message->toDictionary();
       }
 
       return $lint_result;
     } catch (ArcanistNoEngineException $ex) {
       $this->console->writeOut(
         "%s\n",
         pht('No lint engine configured for this project.'));
     } catch (ArcanistNoEffectException $ex) {
       $this->console->writeOut("%s\n", $ex->getMessage());
     }
 
     return null;
   }
 
 
   /**
    * @task lintunit
    */
   private function runUnit() {
     if ($this->getArgument('nounit') ||
         $this->isRawDiffSource() ||
         $this->getArgument('head')) {
       return ArcanistUnitWorkflow::RESULT_SKIP;
     }
 
     $repository_api = $this->getRepositoryAPI();
 
     $this->console->writeOut("%s\n", pht('Running unit tests...'));
     try {
       $argv = $this->getPassthruArgumentsAsArgv('unit');
       if ($repository_api->supportsCommitRanges()) {
         $argv[] = '--rev';
         $argv[] = $repository_api->getBaseCommit();
       }
       $unit_workflow = $this->buildChildWorkflow('unit', $argv);
       $unit_result = $unit_workflow->run();
 
       switch ($unit_result) {
         case ArcanistUnitWorkflow::RESULT_OKAY:
           $this->console->writeOut(
             "<bg:green>** %s **</bg> %s\n",
             pht('UNIT OKAY'),
             pht('No unit test failures.'));
           break;
         case ArcanistUnitWorkflow::RESULT_UNSOUND:
           if ($this->getArgument('ignore-unsound-tests')) {
             echo phutil_console_format(
               "<bg:yellow>** %s **</bg> %s\n",
               pht('UNIT UNSOUND'),
               pht(
                 'Unit testing raised errors, but all '.
                 'failing tests are unsound.'));
           } else {
             $continue = phutil_console_confirm(
               pht(
                 'Unit test results included failures, but all failing tests '.
                 'are known to be unsound. Ignore unsound test failures?'));
             if (!$continue) {
               throw new ArcanistUserAbortException();
             }
           }
           break;
         case ArcanistUnitWorkflow::RESULT_FAIL:
           $this->console->writeOut(
             "<bg:red>** %s **</bg> %s\n",
             pht('UNIT ERRORS'),
             pht('Unit testing raised errors!'));
           $this->getErrorExcuse(
             'unit',
             pht('Unit test results include failures!'),
             'unit-excuses');
           break;
       }
 
       $this->testResults = array();
       foreach ($unit_workflow->getTestResults() as $test) {
         $this->testResults[] = $test->toDictionary();
       }
 
       return $unit_result;
     } catch (ArcanistNoEngineException $ex) {
       $this->console->writeOut(
         "%s\n",
         pht('No unit test engine is configured for this project.'));
     } catch (ArcanistNoEffectException $ex) {
       $this->console->writeOut("%s\n", $ex->getMessage());
     }
 
     return null;
   }
 
   public function getTestResults() {
     return $this->testResults;
   }
 
   private function getSkipExcuse($prompt, $history) {
     $excuse = $this->getArgument('excuse');
 
     if ($excuse === null) {
       $history = $this->getRepositoryAPI()->getScratchFilePath($history);
       $excuse = phutil_console_prompt($prompt, $history);
       if ($excuse == '') {
         throw new ArcanistUserAbortException();
       }
     }
 
     return $excuse;
   }
 
   private function getErrorExcuse($type, $prompt, $history) {
     if ($this->getArgument('excuse')) {
       $this->console->sendMessage(array(
         'type'    => $type,
         'confirm'  => $prompt.' '.pht('Ignore them?'),
       ));
       return;
     }
 
     $history = $this->getRepositoryAPI()->getScratchFilePath($history);
 
     $prompt .= ' '.
       pht('Provide explanation to continue or press Enter to abort.');
     $this->console->writeOut("\n\n%s", phutil_console_wrap($prompt));
     $this->console->sendMessage(array(
       'type'    => $type,
       'prompt'  => pht('Explanation:'),
       'history' => $history,
     ));
   }
 
   public function handleServerMessage(PhutilConsoleMessage $message) {
     $data = $message->getData();
 
     if ($this->getArgument('excuse')) {
       try {
         phutil_console_require_tty();
       } catch (PhutilConsoleStdinNotInteractiveException $ex) {
         $this->excuses[$data['type']] = $this->getArgument('excuse');
         return null;
       }
     }
 
     $response = '';
     if (isset($data['prompt'])) {
       $response = phutil_console_prompt($data['prompt'], idx($data, 'history'));
     } else if (phutil_console_confirm($data['confirm'])) {
       $response = $this->getArgument('excuse');
     }
     if ($response == '') {
       throw new ArcanistUserAbortException();
     }
     $this->excuses[$data['type']] = $response;
     return null;
   }
 
 
 /* -(  Commit and Update Messages  )----------------------------------------- */
 
 
   /**
    * @task message
    */
   private function buildCommitMessage() {
     if ($this->getArgument('only')) {
       return null;
     }
 
     $is_create = $this->getArgument('create');
     $is_update = $this->getArgument('update');
     $is_raw = $this->isRawDiffSource();
     $is_message = $this->getArgument('use-commit-message');
     $is_verbatim = $this->getArgument('verbatim');
 
     if ($is_message) {
       return $this->getCommitMessageFromCommit($is_message);
     }
 
     if ($is_verbatim) {
       return $this->getCommitMessageFromUser();
     }
 
 
     if (!$is_raw && !$is_create && !$is_update) {
       $repository_api = $this->getRepositoryAPI();
       $revisions = $repository_api->loadWorkingCopyDifferentialRevisions(
         $this->getConduit(),
         array(
           'authors' => array($this->getUserPHID()),
           'status'  => 'status-open',
         ));
       if (!$revisions) {
         $is_create = true;
       } else if (count($revisions) == 1) {
         $revision = head($revisions);
         $is_update = $revision['id'];
       } else {
         throw new ArcanistUsageException(
           pht(
             "There are several revisions which match the working copy:\n\n%s\n".
             "Use '%s' to choose one, or '%s' to create a new revision.",
             $this->renderRevisionList($revisions),
             '--update',
             '--create'));
       }
     }
 
     $message = null;
     if ($is_create) {
       $message_file = $this->getArgument('message-file');
       if ($message_file) {
         return $this->getCommitMessageFromFile($message_file);
       } else {
         return $this->getCommitMessageFromUser();
       }
     } else if ($is_update) {
       $revision_id = $this->normalizeRevisionID($is_update);
       if (!is_numeric($revision_id)) {
         throw new ArcanistUsageException(
           pht(
             'Parameter to %s must be a Differential Revision number.',
             '--update'));
       }
       return $this->getCommitMessageFromRevision($revision_id);
     } else {
       // This is --raw without enough info to create a revision, so force just
       // a diff.
       return null;
     }
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromCommit($commit) {
     $text = $this->getRepositoryAPI()->getCommitMessage($commit);
     $message = ArcanistDifferentialCommitMessage::newFromRawCorpus($text);
     $message->pullDataFromConduit($this->getConduit());
     $this->validateCommitMessage($message);
     return $message;
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromUser() {
     $conduit = $this->getConduit();
 
     $template = null;
 
     if (!$this->getArgument('verbatim')) {
       $saved = $this->readScratchFile('create-message');
       if ($saved) {
         $where = $this->getReadableScratchFilePath('create-message');
 
         $preview = explode("\n", $saved);
         $preview = array_shift($preview);
         $preview = trim($preview);
         $preview = id(new PhutilUTF8StringTruncator())
           ->setMaximumGlyphs(64)
           ->truncateString($preview);
 
         if ($preview) {
           $preview = pht('Message begins:')."\n\n       {$preview}\n\n";
         } else {
           $preview = null;
         }
 
         echo pht(
           "You have a saved revision message in '%s'.\n%s".
           "You can use this message, or discard it.",
           $where,
           $preview);
 
         $use = phutil_console_confirm(
           pht('Do you want to use this message?'),
           $default_no = false);
         if ($use) {
           $template = $saved;
         } else {
           $this->removeScratchFile('create-message');
         }
       }
     }
 
     $template_is_default = false;
     $notes = array();
     $included = array();
 
     list($fields, $notes, $included_commits) = $this->getDefaultCreateFields();
     if ($template) {
       $fields = array();
       $notes = array();
     } else {
       if (!$fields) {
         $template_is_default = true;
       }
 
       if ($notes) {
         $commit = head($this->getRepositoryAPI()->getLocalCommitInformation());
         $template = $commit['message'];
       } else {
         $template = $conduit->callMethodSynchronous(
           'differential.getcommitmessage',
           array(
             'revision_id' => null,
             'edit'        => 'create',
             'fields'      => $fields,
           ));
       }
     }
 
     $old_message = $template;
 
     $included = array();
     if ($included_commits) {
       foreach ($included_commits as $commit) {
         $included[] = '        '.$commit;
       }
 
       if (!$this->isRawDiffSource()) {
         $message = pht(
           'Included commits in branch %s:',
           $this->getRepositoryAPI()->getBranchName());
       } else {
         $message = pht('Included commits:');
       }
       $included = array_merge(
         array(
           '',
           $message,
           '',
         ),
         $included);
     }
 
     $issues = array_merge(
       array(
         pht('NEW DIFFERENTIAL REVISION'),
         pht('Describe the changes in this new revision.'),
       ),
       $included,
       array(
         '',
         pht(
           'arc could not identify any existing revision in your working copy.'),
         pht('If you intended to update an existing revision, use:'),
         '',
         '  $ arc diff --update <revision>',
       ));
     if ($notes) {
       $issues = array_merge($issues, array(''), $notes);
     }
 
     $done = false;
     $first = true;
     while (!$done) {
       $template = rtrim($template, "\r\n")."\n\n";
       foreach ($issues as $issue) {
         $template .= rtrim('# '.$issue)."\n";
       }
       $template .= "\n";
 
       if ($first && $this->getArgument('verbatim') && !$template_is_default) {
         $new_template = $template;
       } else {
         $new_template = $this->newInteractiveEditor($template)
           ->setName('new-commit')
           ->editInteractively();
       }
       $first = false;
 
       if ($template_is_default && ($new_template == $template)) {
         throw new ArcanistUsageException(pht('Template not edited.'));
       }
 
       $template = ArcanistCommentRemover::removeComments($new_template);
 
       // With --raw-command, we may not have a repository API.
       if ($this->hasRepositoryAPI()) {
         $repository_api = $this->getRepositoryAPI();
         // special check for whether to amend here. optimizes a common git
         // workflow. we can't do this for mercurial because the mq extension
         // is popular and incompatible with hg commit --amend ; see T2011.
         $should_amend = (count($included_commits) == 1 &&
                          $repository_api instanceof ArcanistGitAPI &&
                          $this->shouldAmend());
       } else {
         $should_amend = false;
       }
 
       if ($should_amend) {
         $wrote = (rtrim($old_message) != rtrim($template));
         if ($wrote) {
           $repository_api->amendCommit($template);
           $where = pht('commit message');
         }
       } else {
         $wrote = $this->writeScratchFile('create-message', $template);
         $where = "'".$this->getReadableScratchFilePath('create-message')."'";
       }
 
       try {
         $message = ArcanistDifferentialCommitMessage::newFromRawCorpus(
           $template);
         $message->pullDataFromConduit($conduit);
         $this->validateCommitMessage($message);
         $done = true;
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         echo pht('Commit message has errors:')."\n\n";
         $issues = array(pht('Resolve these errors:'));
         foreach ($ex->getParserErrors() as $error) {
           echo phutil_console_wrap("- ".$error."\n", 6);
           $issues[] = '  - '.$error;
         }
         echo "\n";
         echo pht('You must resolve these errors to continue.');
         $again = phutil_console_confirm(
           pht('Do you want to edit the message?'),
           $default_no = false);
         if ($again) {
           // Keep going.
         } else {
           $saved = null;
           if ($wrote) {
             $saved = pht('A copy was saved to %s.', $where);
           }
           throw new ArcanistUsageException(
             pht('Message has unresolved errors.')." {$saved}");
         }
       } catch (Exception $ex) {
         if ($wrote) {
           echo phutil_console_wrap(pht('(Message saved to %s.)', $where)."\n");
         }
         throw $ex;
       }
     }
 
     return $message;
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromFile($file) {
     $conduit = $this->getConduit();
 
     $data = Filesystem::readFile($file);
     $message = ArcanistDifferentialCommitMessage::newFromRawCorpus($data);
     $message->pullDataFromConduit($conduit);
 
     $this->validateCommitMessage($message);
 
     return $message;
   }
 
 
   /**
    * @task message
    */
   private function getCommitMessageFromRevision($revision_id) {
     $id = $revision_id;
 
     $revision = $this->getConduit()->callMethodSynchronous(
       'differential.query',
       array(
         'ids' => array($id),
       ));
     $revision = head($revision);
 
     if (!$revision) {
       throw new ArcanistUsageException(
         pht(
           "Revision '%s' does not exist!",
           $revision_id));
     }
 
     $this->checkRevisionOwnership($revision);
 
     // TODO: Save this status to improve a prompt later. See PHI458. This is
     // extra awful until we move to "differential.revision.search" because
     // the "differential.query" method doesn't return a real draft status for
     // compatibility.
     $this->revisionIsDraft = (idx($revision, 'statusName') === 'Draft');
 
     $message = $this->getConduit()->callMethodSynchronous(
       'differential.getcommitmessage',
       array(
         'revision_id' => $id,
         'edit'        => false,
       ));
     $this->commitMessageFromRevision = $message;
 
     $obj = ArcanistDifferentialCommitMessage::newFromRawCorpus($message);
     $obj->pullDataFromConduit($this->getConduit());
 
     return $obj;
   }
 
 
   /**
    * @task message
    */
   private function validateCommitMessage(
     ArcanistDifferentialCommitMessage $message) {
     $futures = array();
 
     $revision_id = $message->getRevisionID();
     if ($revision_id) {
       $futures['revision'] = $this->getConduit()->callMethod(
         'differential.query',
         array(
           'ids' => array($revision_id),
         ));
     }
 
     $reviewers = $message->getFieldValue('reviewerPHIDs');
     if ($reviewers) {
       $futures['reviewers'] = $this->getConduit()->callMethod(
         'user.query',
         array(
           'phids' => $reviewers,
         ));
     }
 
     foreach (new FutureIterator($futures) as $key => $future) {
       $result = $future->resolve();
       switch ($key) {
         case 'revision':
           if (empty($result)) {
             throw new ArcanistUsageException(
               pht(
                 'There is no revision %s.',
                 "D{$revision_id}"));
           }
           $this->checkRevisionOwnership(head($result));
           break;
         case 'reviewers':
           $untils = array();
           foreach ($result as $user) {
             if (idx($user, 'currentStatus') == 'away') {
               $untils[] = $user['currentStatusUntil'];
             }
           }
           if (count($untils) == count($reviewers)) {
             $until = date('l, M j Y', min($untils));
             $confirm = pht(
               'All reviewers are away until %s. Continue anyway?',
               $until);
             if (!phutil_console_confirm($confirm)) {
               throw new ArcanistUsageException(
                 pht('Specify available reviewers and retry.'));
             }
           }
           break;
       }
     }
 
   }
 
 
   /**
    * @task message
    */
   private function getUpdateMessage(array $fields, $template = '') {
     if ($this->getArgument('raw')) {
       throw new ArcanistUsageException(
         pht(
           "When using '%s' to update a revision, specify an update message ".
           "with '%s'. (Normally, we'd launch an editor to ask you for a ".
           "message, but can not do that because stdin is the diff source.)",
           '--raw',
           '--message'));
     }
 
     // When updating a revision using git without specifying '--message', try
     // to prefill with the message in HEAD if it isn't a template message. The
     // idea is that if you do:
     //
     //  $ git commit -a -m 'fix some junk'
     //  $ arc diff
     //
     // ...you shouldn't have to retype the update message. Similar things apply
     // to Mercurial.
 
     if ($template == '') {
       $comments = $this->getDefaultUpdateMessage();
 
       $template = sprintf(
         "%s\n\n# %s\n#\n# %s\n# %s\n#\n# %s\n#  $ %s\n\n",
         rtrim($comments),
         pht(
           'Updating %s: %s',
           "D{$fields['revisionID']}",
           $fields['title']),
         pht(
           'Enter a brief description of the changes included in this update.'),
         pht('The first line is used as subject, next lines as comment.'),
         pht('If you intended to create a new revision, use:'),
         'arc diff --create');
     }
 
     $comments = $this->newInteractiveEditor($template)
       ->setName('differential-update-comments')
       ->editInteractively();
 
     return $comments;
   }
 
   private function getDefaultCreateFields() {
     $result = array(array(), array(), array());
 
     if ($this->isRawDiffSource()) {
       return $result;
     }
 
     $repository_api = $this->getRepositoryAPI();
     $local = $repository_api->getLocalCommitInformation();
     if ($local) {
       $result = $this->parseCommitMessagesIntoFields($local);
       if ($this->getArgument('create')) {
         unset($result[0]['revisionID']);
       }
     }
 
     $result[0] = $this->dispatchWillBuildEvent($result[0]);
 
     return $result;
   }
 
   /**
    * Convert a list of commits from `getLocalCommitInformation()` into
    * a format usable by arc to create a new diff. Specifically, we emit:
    *
    *   - A dictionary of commit message fields.
    *   - A list of errors encountered while parsing the messages.
    *   - A human-readable list of the commits themselves.
    *
    * For example, if the user runs "arc diff HEAD^^^" and selects a diff range
    * which includes several diffs, we attempt to merge them somewhat
    * intelligently into a single message, because we can only send one
    * "Summary:", "Reviewers:", etc., field to Differential. We also return
    * errors (e.g., if the user typed a reviewer name incorrectly) and a
    * summary of the commits themselves.
    *
    * @param dict  Local commit information.
    * @return list Complex output, see summary.
    * @task message
    */
   private function parseCommitMessagesIntoFields(array $local) {
     $conduit = $this->getConduit();
     $local = ipull($local, null, 'commit');
 
     // If the user provided "--reviewers" or "--ccs", add a faux message to
     // the list with the implied fields.
 
     $faux_message = array();
     if ($this->getArgument('reviewers')) {
       $faux_message[] = pht('Reviewers: %s', $this->getArgument('reviewers'));
     }
     if ($this->getArgument('cc')) {
       $faux_message[] = pht('CC: %s', $this->getArgument('cc'));
     }
 
     // NOTE: For now, this isn't a real field, so it just ends up as the first
     // part of the summary.
     $depends_ref = $this->getDependsOnRevisionRef();
     if ($depends_ref) {
       $faux_message[] = pht(
         'Depends on %s. ',
         $depends_ref->getMonogram());
     }
 
     // See T12069. After T10312, the first line of a message is always parsed
     // as a title. Add a placeholder so "Reviewers" and "CC" are never the
     // first line.
     $placeholder_title = pht('<placeholder>');
 
     if ($faux_message) {
       array_unshift($faux_message, $placeholder_title);
       $faux_message = implode("\n\n", $faux_message);
       $local = array(
         '(Flags)     ' => array(
           'message' => $faux_message,
           'summary' => pht('Command-Line Flags'),
         ),
       ) + $local;
     }
 
     // Build a human-readable list of the commits, so we can show the user which
     // commits are included in the diff.
     $included = array();
     foreach ($local as $hash => $info) {
       $included[] = substr($hash, 0, 12).' '.$info['summary'];
     }
 
     // Parse all of the messages into fields.
     $messages = array();
     foreach ($local as $hash => $info) {
       $text = $info['message'];
       $obj = ArcanistDifferentialCommitMessage::newFromRawCorpus($text);
       $messages[$hash] = $obj;
     }
 
     $notes = array();
     $fields = array();
     foreach ($messages as $hash => $message) {
       try {
         $message->pullDataFromConduit($conduit, $partial = true);
         $fields[$hash] = $message->getFields();
       } catch (ArcanistDifferentialCommitMessageParserException $ex) {
         if ($this->getArgument('verbatim')) {
           // In verbatim mode, just bail when we hit an error. The user can
           // rerun without --verbatim if they want to fix it manually. Most
           // users will probably `git commit --amend` instead.
           throw $ex;
         }
         $fields[$hash] = $message->getFields();
 
         $frev = substr($hash, 0, 12);
         $notes[] = pht(
           'NOTE: commit %s could not be completely parsed:',
           $frev);
         foreach ($ex->getParserErrors() as $error) {
           $notes[] = "  - {$error}";
         }
       }
     }
 
     // Merge commit message fields. We do this somewhat-intelligently so that
     // multiple "Reviewers" or "CC" fields will merge into the concatenation
     // of all values.
 
     // We have special parsing rules for 'title' because we can't merge
     // multiple titles, and one-line commit messages like "fix stuff" will
     // parse as titles. Instead, pick the first title we encounter. When we
     // encounter subsequent titles, treat them as part of the summary. Then
     // we merge all the summaries together below.
 
     $result = array();
 
     // Process fields in oldest-first order, so earlier commits get to set the
     // title of record and reviewers/ccs are listed in chronological order.
     $fields = array_reverse($fields);
 
     foreach ($fields as $hash => $dict) {
       $title = idx($dict, 'title');
       if (!strlen($title)) {
         continue;
       }
 
       if ($title === $placeholder_title) {
         continue;
       }
 
       if (!isset($result['title'])) {
         // We don't have a title yet, so use this one.
         $result['title'] = $title;
       } else {
         // We already have a title, so merge this new title into the summary.
         $summary = idx($dict, 'summary');
         if ($summary) {
           $summary = $title."\n\n".$summary;
         } else {
           $summary = $title;
         }
         $fields[$hash]['summary'] = $summary;
       }
     }
 
     // Now, merge all the other fields in a general sort of way.
 
     foreach ($fields as $hash => $dict) {
       foreach ($dict as $key => $value) {
         if ($key == 'title') {
           // This has been handled above, and either assigned directly or
           // merged into the summary.
           continue;
         }
 
         if (is_array($value)) {
           // For array values, merge the arrays, appending the new values.
           // Examples are "Reviewers" and "Cc", where this produces a list of
           // all users specified as reviewers.
           $cur = idx($result, $key, array());
           $new = array_merge($cur, $value);
           $result[$key] = $new;
           continue;
         } else {
           if (!strlen(trim($value))) {
             // Ignore empty fields.
             continue;
           }
 
           // For string values, append the new field to the old field with
           // a blank line separating them. Examples are "Test Plan" and
           // "Summary".
           $cur = idx($result, $key, '');
           if (strlen($cur)) {
             $new = $cur."\n\n".$value;
           } else {
             $new = $value;
           }
           $result[$key] = $new;
         }
       }
     }
 
     return array($result, $notes, $included);
   }
 
   private function getDefaultUpdateMessage() {
     if ($this->isRawDiffSource()) {
       return null;
     }
 
     $repository_api = $this->getRepositoryAPI();
     if ($repository_api instanceof ArcanistGitAPI) {
       return $this->getGitUpdateMessage();
     }
 
     if ($repository_api instanceof ArcanistMercurialAPI) {
       return $this->getMercurialUpdateMessage();
     }
 
     return null;
   }
 
   /**
    * Retrieve the git messages between HEAD and the last update.
    *
    * @task message
    */
   private function getGitUpdateMessage() {
     $repository_api = $this->getRepositoryAPI();
 
     $parser = $this->newDiffParser();
     $commit_messages = $repository_api->getGitCommitLog();
     $commit_messages = $parser->parseDiff($commit_messages);
 
     if (count($commit_messages) == 1) {
       // If there's only one message, assume this is an amend-based workflow and
       // that using it to prefill doesn't make sense.
       return null;
     }
 
     // We have more than one message, so figure out which ones are new. We
     // do this by pulling the current diff and comparing commit hashes in the
     // working copy with attached commit hashes. It's not super important that
     // we always get this 100% right, we're just trying to do something
     // reasonable.
 
     $local = $this->loadActiveLocalCommitInfo();
     $hashes = ipull($local, null, 'commit');
 
     $usable = array();
     foreach ($commit_messages as $message) {
       $text = $message->getMetadata('message');
 
       $parsed = ArcanistDifferentialCommitMessage::newFromRawCorpus($text);
       if ($parsed->getRevisionID()) {
         // If this is an amended commit message with a revision ID, it's
         // certainly not new. Stop marking commits as usable and break out.
         break;
       }
 
       if (isset($hashes[$message->getCommitHash()])) {
         // If this commit is currently part of the diff, stop using commit
         // messages, since anything older than this isn't new.
         break;
       }
 
       // Otherwise, this looks new, so it's a usable commit message.
       $usable[] = $text;
     }
 
     if (!$usable) {
       // No new commit messages, so we don't have anywhere to start from.
       return null;
     }
 
     return $this->formatUsableLogs($usable);
   }
 
   /**
    * Retrieve the hg messages between tip and the last update.
    *
    * @task message
    */
   private function getMercurialUpdateMessage() {
     $repository_api = $this->getRepositoryAPI();
 
     $messages = $repository_api->getCommitMessageLog();
 
     if (count($messages) == 1) {
       // If there's only one message, assume this is an amend-based workflow and
       // that using it to prefill doesn't make sense.
       return null;
     }
 
     $local = $this->loadActiveLocalCommitInfo();
     $hashes = ipull($local, null, 'commit');
 
     $usable = array();
     foreach ($messages as $rev => $message) {
       if (isset($hashes[$rev])) {
         // If this commit is currently part of the active diff on the revision,
         // stop using commit messages, since anything older than this isn't new.
         break;
       }
 
       // Otherwise, this looks new, so it's a usable commit message.
       $usable[] = $message;
     }
 
     if (!$usable) {
       // No new commit messages, so we don't have anywhere to start from.
       return null;
     }
 
     return $this->formatUsableLogs($usable);
   }
 
 
   /**
    * Format log messages to prefill a diff update.
    *
    * @task message
    */
   private function formatUsableLogs(array $usable) {
     // Flip messages so they'll read chronologically (oldest-first) in the
     // template, e.g.:
     //
     //   - Added foobar.
     //   - Fixed foobar bug.
     //   - Documented foobar.
 
     $usable = array_reverse($usable);
     $default = array();
     foreach ($usable as $message) {
       // Pick the first line out of each message.
       $text = trim($message);
       $text = head(explode("\n", $text));
       $default[] = '  - '.$text."\n";
     }
 
     return implode('', $default);
   }
 
   private function loadActiveLocalCommitInfo() {
     $current_diff = $this->getConduit()->callMethodSynchronous(
       'differential.querydiffs',
       array(
         'revisionIDs' => array($this->revisionID),
       ));
     $current_diff = head($current_diff);
 
     $properties = idx($current_diff, 'properties', array());
     return idx($properties, 'local:commits', array());
   }
 
 
 /* -(  Diff Specification  )------------------------------------------------- */
 
 
   /**
    * @task diffspec
    */
   private function getLintStatus($lint_result) {
     $map = array(
       ArcanistLintWorkflow::RESULT_OKAY       => 'okay',
       ArcanistLintWorkflow::RESULT_ERRORS     => 'fail',
       ArcanistLintWorkflow::RESULT_WARNINGS   => 'warn',
       ArcanistLintWorkflow::RESULT_SKIP       => 'skip',
     );
     return idx($map, $lint_result, 'none');
   }
 
 
   /**
    * @task diffspec
    */
   private function getUnitStatus($unit_result) {
     $map = array(
       ArcanistUnitWorkflow::RESULT_OKAY       => 'okay',
       ArcanistUnitWorkflow::RESULT_FAIL       => 'fail',
       ArcanistUnitWorkflow::RESULT_UNSOUND    => 'warn',
       ArcanistUnitWorkflow::RESULT_SKIP       => 'skip',
     );
     return idx($map, $unit_result, 'none');
   }
 
 
   /**
    * @task diffspec
    */
   private function buildDiffSpecification() {
 
     $base_revision  = null;
     $base_path      = null;
     $vcs            = null;
     $repo_uuid      = null;
     $parent         = null;
     $source_path    = null;
     $branch         = null;
     $bookmark       = null;
 
     if (!$this->isRawDiffSource()) {
       $repository_api = $this->getRepositoryAPI();
 
       $base_revision  = $repository_api->getSourceControlBaseRevision();
       $base_path      = $repository_api->getSourceControlPath();
       $vcs            = $repository_api->getSourceControlSystemName();
       $source_path    = $repository_api->getPath();
       $branch         = $repository_api->getBranchName();
       $repo_uuid      = $repository_api->getRepositoryUUID();
 
       if ($repository_api instanceof ArcanistGitAPI) {
         $info = $this->getGitParentLogInfo();
         if ($info['parent']) {
           $parent = $info['parent'];
         }
         if ($info['base_revision']) {
           $base_revision = $info['base_revision'];
         }
         if ($info['base_path']) {
           $base_path = $info['base_path'];
         }
         if ($info['uuid']) {
           $repo_uuid = $info['uuid'];
         }
       } else if ($repository_api instanceof ArcanistMercurialAPI) {
 
         $bookmark = $repository_api->getActiveBookmark();
         $svn_info = $repository_api->getSubversionInfo();
         $repo_uuid = idx($svn_info, 'uuid');
         $base_path = idx($svn_info, 'base_path', $base_path);
         $base_revision = idx($svn_info, 'base_revision', $base_revision);
 
         // TODO: provide parent info
 
       }
     }
 
     $data = array(
       'sourceMachine'             => php_uname('n'),
       'sourcePath'                => $source_path,
       'branch'                    => $branch,
       'bookmark'                  => $bookmark,
       'sourceControlSystem'       => $vcs,
       'sourceControlPath'         => $base_path,
       'sourceControlBaseRevision' => $base_revision,
       'creationMethod'            => 'arc',
     );
 
     if (!$this->isRawDiffSource()) {
       $repository_phid = $this->getRepositoryPHID();
       if ($repository_phid) {
         $data['repositoryPHID'] = $repository_phid;
       }
     }
 
     return $data;
   }
 
 
 /* -(  Diff Properties  )---------------------------------------------------- */
 
 
   /**
    * Update lint information for the diff.
    *
    * @return void
    *
    * @task diffprop
    */
   private function updateLintDiffProperty() {
     if (strlen($this->excuses['lint'])) {
       $this->updateDiffProperty(
         'arc:lint-excuse',
         json_encode($this->excuses['lint']));
     }
 
     if (!$this->hitAutotargets) {
       if ($this->unresolvedLint) {
         $this->updateDiffProperty(
           'arc:lint',
           json_encode($this->unresolvedLint));
       }
     }
   }
 
 
   /**
    * Update unit test information for the diff.
    *
    * @return void
    *
    * @task diffprop
    */
   private function updateUnitDiffProperty() {
     if (strlen($this->excuses['unit'])) {
       $this->updateDiffProperty('arc:unit-excuse',
         json_encode($this->excuses['unit']));
     }
 
     if (!$this->hitAutotargets) {
       if ($this->testResults) {
         $this->updateDiffProperty('arc:unit', json_encode($this->testResults));
       }
     }
   }
 
 
   /**
    * Update local commit information for the diff.
    *
    * @task diffprop
    */
   private function updateLocalDiffProperty() {
     if ($this->isRawDiffSource()) {
       return;
     }
 
     $local_info = $this->getRepositoryAPI()->getLocalCommitInformation();
     if (!$local_info) {
       return;
     }
 
     $this->updateDiffProperty('local:commits', json_encode($local_info));
   }
 
   private function updateOntoDiffProperty() {
     $onto = $this->getDiffOntoTargets();
 
     if (!$onto) {
       return;
     }
 
     $this->updateDiffProperty('arc:onto', json_encode($onto));
   }
 
   private function getDiffOntoTargets() {
     if ($this->isRawDiffSource()) {
       return null;
     }
 
     $api = $this->getRepositoryAPI();
 
     if (!($api instanceof ArcanistGitAPI)) {
       return null;
     }
 
     // If we track an upstream branch either directly or indirectly, use that.
     $branch = $api->getBranchName();
     if (strlen($branch)) {
       $upstream_path = $api->getPathToUpstream($branch);
       $remote_branch = $upstream_path->getRemoteBranchName();
       if (strlen($remote_branch)) {
         return array(
           array(
             'type' => 'branch',
             'name' => $remote_branch,
             'kind' => 'upstream',
           ),
         );
       }
     }
 
     // If "arc.land.onto.default" is configured, use that.
     $config_key = 'arc.land.onto.default';
     $onto = $this->getConfigFromAnySource($config_key);
     if (strlen($onto)) {
       return array(
         array(
           'type' => 'branch',
           'name' => $onto,
           'kind' => 'arc.land.onto.default',
         ),
       );
     }
 
     return null;
   }
 
   /**
    * Update an arbitrary diff property.
    *
    * @param string Diff property name.
    * @param string Diff property value.
    * @return void
    *
    * @task diffprop
    */
   private function updateDiffProperty($name, $data) {
     $this->diffPropertyFutures[] = $this->getConduit()->callMethod(
       'differential.setdiffproperty',
       array(
         'diff_id' => $this->getDiffID(),
         'name'    => $name,
         'data'    => $data,
       ));
   }
 
   /**
    * Wait for finishing all diff property updates.
    *
    * @return void
    *
    * @task diffprop
    */
   private function resolveDiffPropertyUpdates() {
     id(new FutureIterator($this->diffPropertyFutures))
       ->resolveAll();
     $this->diffPropertyFutures = array();
   }
 
   private function dispatchWillCreateRevisionEvent(array $fields) {
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_REVISION_WILLCREATEREVISION,
       array(
         'specification' => $fields,
       ));
 
     return $event->getValue('specification');
   }
 
   private function dispatchWillBuildEvent(array $fields) {
     $event = $this->dispatchEvent(
       ArcanistEventType::TYPE_DIFF_WILLBUILDMESSAGE,
       array(
         'fields' => $fields,
       ));
 
     return $event->getValue('fields');
   }
 
   private function checkRevisionOwnership(array $revision) {
     if ($revision['authorPHID'] == $this->getUserPHID()) {
       return;
     }
 
     $id = $revision['id'];
     $title = $revision['title'];
 
     $prompt = pht(
       "You don't own revision %s: \"%s\". Normally, you should ".
       "only update revisions you own. You can \"Commandeer\" this revision ".
       "from the web interface if you want to become the owner.\n\n".
       "Update this revision anyway?",
       "D{$id}",
       $title);
 
     $ok = phutil_console_confirm($prompt, $default_no = true);
     if (!$ok) {
       throw new ArcanistUsageException(
         pht('Aborted update of revision: You are not the owner.'));
     }
   }
 
 
 /* -(  File Uploads  )------------------------------------------------------- */
 
 
   private function uploadFilesForChanges(array $changes) {
     assert_instances_of($changes, 'ArcanistDiffChange');
 
     // Collect all the files we need to upload.
 
     $need_upload = array();
     foreach ($changes as $key => $change) {
       if ($change->getFileType() != ArcanistDiffChangeType::FILE_BINARY) {
         continue;
       }
 
       if ($this->getArgument('skip-binaries')) {
         continue;
       }
 
       $name = basename($change->getCurrentPath());
 
       $need_upload[] = array(
         'type' => 'old',
         'name' => $name,
         'data' => $change->getOriginalFileData(),
         'change' => $change,
       );
 
       $need_upload[] = array(
         'type' => 'new',
         'name' => $name,
         'data' => $change->getCurrentFileData(),
         'change' => $change,
       );
     }
 
     if (!$need_upload) {
       return;
     }
 
     // Determine mime types and file sizes. Update changes from "binary" to
     // "image" if the file is an image. Set image metadata.
 
     $type_image = ArcanistDiffChangeType::FILE_IMAGE;
     foreach ($need_upload as $key => $spec) {
       $change = $need_upload[$key]['change'];
 
       if ($spec['data'] === null) {
         // This covers the case where a file was added or removed; we don't
         // need to upload the other half of it (e.g., the old file data for
         // a file which was just added). This is distinct from an empty
         // file, which we do upload.
         unset($need_upload[$key]);
         continue;
       }
 
       $type = $spec['type'];
       $size = strlen($spec['data']);
 
       $change->setMetadata("{$type}:file:size", $size);
 
       $mime = $this->getFileMimeType($spec['data']);
       if (preg_match('@^image/@', $mime)) {
         $change->setFileType($type_image);
       }
 
       $change->setMetadata("{$type}:file:mime-type", $mime);
     }
 
     $uploader = id(new ArcanistFileUploader())
       ->setConduitClient($this->getConduit());
 
     foreach ($need_upload as $key => $spec) {
       $ref = id(new ArcanistFileDataRef())
         ->setName($spec['name'])
         ->setData($spec['data']);
 
       $uploader->addFile($ref, $key);
     }
 
     $files = $uploader->uploadFiles();
 
     $errors = false;
     foreach ($files as $key => $file) {
       if ($file->getErrors()) {
         unset($files[$key]);
         $errors = true;
         echo pht(
           'Failed to upload binary "%s".',
           $file->getName());
       }
     }
 
     if ($errors) {
       $prompt = pht('Continue?');
       $ok = phutil_console_confirm($prompt, $default_no = false);
       if (!$ok) {
         throw new ArcanistUsageException(
           pht(
             'Aborted due to file upload failure. You can use %s '.
             'to skip binary uploads.',
             '--skip-binaries'));
       }
     }
 
     foreach ($files as $key => $file) {
       $spec = $need_upload[$key];
       $phid = $file->getPHID();
 
       $change = $spec['change'];
       $type = $spec['type'];
       $change->setMetadata("{$type}:binary-phid", $phid);
 
       echo pht('Uploaded binary data for "%s".', $file->getName())."\n";
     }
 
     echo pht('Upload complete.')."\n";
   }
 
   private function getFileMimeType($data) {
     $tmp = new TempFile();
     Filesystem::writeFile($tmp, $data);
     return Filesystem::getMimeType($tmp);
   }
 
   private function shouldOpenCreatedObjectsInBrowser() {
     return $this->getArgument('browse');
   }
 
   private function submitChangesToStagingArea($id) {
     $result = $this->pushChangesToStagingArea($id);
 
     // We'll either get a failure constant on error, or a list of pushed
     // refs on success.
     $ok = is_array($result);
 
     if ($ok) {
       $staging = array(
         'status' => self::STAGING_PUSHED,
         'refs' => $result,
       );
     } else {
       $staging = array(
         'status' => $result,
         'refs' => array(),
       );
     }
 
     $this->updateDiffProperty(
       'arc.staging',
       phutil_json_encode($staging));
   }
 
   private function pushChangesToStagingArea($id) {
     if ($this->getArgument('skip-staging')) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Flag --skip-staging was specified.'));
       return self::STAGING_USER_SKIP;
     }
 
     if ($this->isRawDiffSource()) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Raw changes can not be pushed to a staging area.'));
       return self::STAGING_DIFF_RAW;
     }
 
     if (!$this->getRepositoryPHID()) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Unable to determine repository for this change.'));
       return self::STAGING_REPOSITORY_UNKNOWN;
     }
 
     $staging = $this->getRepositoryStagingConfiguration();
     if ($staging === null) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('The server does not support staging areas.'));
       return self::STAGING_REPOSITORY_UNAVAILABLE;
     }
 
     $supported = idx($staging, 'supported');
     if (!$supported) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('Phabricator does not support staging areas for this repository.'));
       return self::STAGING_REPOSITORY_UNSUPPORTED;
     }
 
     $staging_uri = idx($staging, 'uri');
     if (!$staging_uri) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('No staging area is configured for this repository.'));
       return self::STAGING_REPOSITORY_UNCONFIGURED;
     }
 
     $api = $this->getRepositoryAPI();
     if (!($api instanceof ArcanistGitAPI)) {
       $this->writeInfo(
         pht('SKIP STAGING'),
         pht('This client version does not support staging this repository.'));
       return self::STAGING_CLIENT_UNSUPPORTED;
     }
 
     $commit = $api->getHeadCommit();
     $prefix = idx($staging, 'prefix', 'phabricator');
 
     $base_tag = "refs/tags/{$prefix}/base/{$id}";
     $diff_tag = "refs/tags/{$prefix}/diff/{$id}";
 
     $this->writeOkay(
       pht('PUSH STAGING'),
       pht('Pushing changes to staging area...'));
 
     $push_flags = array();
     if (version_compare($api->getGitVersion(), '1.8.2', '>=')) {
       $push_flags[] = '--no-verify';
     }
 
     $refs = array();
 
     $remote = array(
       'uri' => $staging_uri,
     );
 
     // If the base commit is a real commit, we're going to push it. We don't
     // use this, but pushing it to a ref reduces the amount of redundant work
     // that Git does on later pushes by helping it figure out that the remote
     // already has most of the history. See T10509.
 
     // In the future, we could avoid this push if the staging area is the same
     // as the main repository, or if the staging area is a virtual repository.
     // In these cases, the staging area should automatically have up-to-date
     // refs.
     $base_commit = $api->getSourceControlBaseRevision();
     if ($base_commit !== ArcanistGitAPI::GIT_MAGIC_ROOT_COMMIT) {
       $refs[] = array(
         'ref' => $base_tag,
         'type' => 'base',
         'commit' => $base_commit,
         'remote' => $remote,
       );
     }
 
     // We're always going to push the change itself.
     $refs[] = array(
       'ref' => $diff_tag,
       'type' => 'diff',
       'commit' => $commit,
       'remote' => $remote,
     );
 
     $ref_list = array();
     foreach ($refs as $ref) {
       $ref_list[] = $ref['commit'].':'.$ref['ref'];
     }
 
     $err = phutil_passthru(
       'git push %Ls -- %s %Ls',
       $push_flags,
       $staging_uri,
       $ref_list);
 
     if ($err) {
       $this->writeWarn(
         pht('STAGING FAILED'),
         pht('Unable to push changes to the staging area.'));
 
       throw new ArcanistUsageException(
         pht(
           'Failed to push changes to staging area. Correct the issue, or '.
           'use --skip-staging to skip this step.'));
     }
 
     return $refs;
   }
 
 
   /**
    * Try to upload lint and unit test results into modern Harbormaster build
    * targets.
    *
    * @return bool True if everything was uploaded to build targets.
    */
   private function updateAutotargets($diff_phid, $unit_result) {
     $lint_key = 'arcanist.lint';
     $unit_key = 'arcanist.unit';
 
     try {
       $result = $this->getConduit()->callMethodSynchronous(
         'harbormaster.queryautotargets',
         array(
           'objectPHID' => $diff_phid,
           'targetKeys' => array(
             $lint_key,
             $unit_key,
           ),
         ));
       $targets = idx($result, 'targetMap', array());
     } catch (Exception $ex) {
       return false;
     }
 
     $futures = array();
 
     $lint_target = idx($targets, $lint_key);
     if ($lint_target) {
       $lint = nonempty($this->unresolvedLint, array());
       foreach ($lint as $key => $message) {
         $lint[$key] = $this->getModernLintDictionary($message);
       }
 
       // Consider this target to have failed if there are any unresolved
       // errors or warnings.
       $type = 'pass';
       foreach ($lint as $message) {
         switch (idx($message, 'severity')) {
           case ArcanistLintSeverity::SEVERITY_WARNING:
           case ArcanistLintSeverity::SEVERITY_ERROR:
             $type = 'fail';
             break;
         }
       }
 
       $futures[] = $this->getConduit()->callMethod(
         'harbormaster.sendmessage',
         array(
           'buildTargetPHID' => $lint_target,
           'lint' => array_values($lint),
           'type' => $type,
         ));
     }
 
     $unit_target = idx($targets, $unit_key);
     if ($unit_target) {
       $unit = nonempty($this->testResults, array());
       foreach ($unit as $key => $message) {
         $unit[$key] = $this->getModernUnitDictionary($message);
       }
 
       $type = ArcanistUnitWorkflow::getHarbormasterTypeFromResult($unit_result);
 
       $futures[] = $this->getConduit()->callMethod(
         'harbormaster.sendmessage',
         array(
           'buildTargetPHID' => $unit_target,
           'unit' => array_values($unit),
           'type' => $type,
         ));
     }
 
     try {
       foreach (new FutureIterator($futures) as $future) {
         $future->resolve();
       }
       return true;
     } catch (Exception $ex) {
       // TODO: Eventually, we should expect these to succeed if we get this
       // far, but just log errors for now.
       phlog($ex);
       return false;
     }
   }
 
   private function getDependsOnRevisionRef() {
     $api = $this->getRepositoryAPI();
     $base_ref = $api->getBaseCommitRef();
 
     $state_ref = $this->newWorkingCopyStateRef()
       ->setCommitRef($base_ref);
 
     $this->newRefQuery(array($state_ref))
       ->needHardpoints(
         array(
           'revisionRefs',
         ))
       ->execute();
 
     $revision_refs = $state_ref->getRevisionRefs();
     $viewer_phid = $this->getUserPHID();
 
     foreach ($revision_refs as $key => $revision_ref) {
       // Don't automatically depend on closed revisions.
       if ($revision_ref->isClosed()) {
         unset($revision_refs[$key]);
         continue;
       }
 
       // Don't automatically depend on revisions authored by other users.
       if ($revision_ref->getAuthorPHID() != $viewer_phid) {
         unset($revision_refs[$key]);
         continue;
       }
     }
 
     if (!$revision_refs) {
       return null;
     }
 
     if (count($revision_refs) > 1) {
       return null;
     }
 
     return head($revision_refs);
   }
 
 }
diff --git a/src/workflow/ArcanistPatchWorkflow.php b/src/workflow/ArcanistPatchWorkflow.php
index 227b020f..a2b3fe40 100644
--- a/src/workflow/ArcanistPatchWorkflow.php
+++ b/src/workflow/ArcanistPatchWorkflow.php
@@ -1,1118 +1,1111 @@
 <?php
 
 /**
  * Applies changes from Differential or a file to the working copy.
  */
 final class ArcanistPatchWorkflow extends ArcanistWorkflow {
 
   const SOURCE_BUNDLE         = 'bundle';
   const SOURCE_PATCH          = 'patch';
   const SOURCE_REVISION       = 'revision';
   const SOURCE_DIFF           = 'diff';
 
   private $source;
   private $sourceParam;
 
   public function getWorkflowName() {
     return 'patch';
   }
 
   public function getCommandSynopses() {
     return phutil_console_format(<<<EOTEXT
       **patch** __D12345__
       **patch** __--revision__ __revision_id__
       **patch** __--diff__ __diff_id__
       **patch** __--patch__ __file__
       **patch** __--arcbundle__ __bundlefile__
 EOTEXT
       );
   }
 
   public function getCommandHelp() {
     return phutil_console_format(<<<EOTEXT
           Supports: git, svn, hg
           Apply the changes in a Differential revision, patchfile, or arc
           bundle to the working copy.
 EOTEXT
       );
   }
 
   public function getArguments() {
     return array(
       'revision' => array(
         'param' => 'revision_id',
         'paramtype' => 'complete',
         'help' => pht(
           "Apply changes from a Differential revision, using the most recent ".
           "diff that has been attached to it. You can run '%s' as a shorthand.",
           'arc patch D12345'),
       ),
       'diff' => array(
         'param' => 'diff_id',
         'help' => pht(
           'Apply changes from a Differential diff. Normally you want to use '.
           '%s to get the most recent changes, but you can specifically apply '.
           'an out-of-date diff or a diff which was never attached to a '.
           'revision by using this flag.',
           '--revision'),
       ),
       'arcbundle' => array(
         'param' => 'bundlefile',
         'paramtype' => 'file',
         'help' => pht(
           "Apply changes from an arc bundle generated with '%s'.",
           'arc export'),
       ),
       'patch' => array(
         'param' => 'patchfile',
         'paramtype' => 'file',
         'help' => pht(
           'Apply changes from a git patchfile or unified patchfile.'),
       ),
       'encoding' => array(
         'param' => 'encoding',
         'help' => pht(
           'Attempt to convert non UTF-8 patch into specified encoding.'),
       ),
       'update' => array(
         'supports' => array('git', 'svn', 'hg'),
         'help' => pht(
           'Update the local working copy before applying the patch.'),
         'conflicts' => array(
           'nobranch' => true,
           'bookmark' => true,
         ),
       ),
       'nocommit' => array(
         'supports' => array('git', 'hg'),
         'help' => pht(
           'Normally under git/hg, if the patch is successful, the changes '.
           'are committed to the working copy. This flag prevents the commit.'),
       ),
       'skip-dependencies' => array(
         'supports' => array('git', 'hg'),
         'help' => pht(
           'Normally, if a patch has dependencies that are not present in the '.
           'working copy, arc tries to apply them as well. This flag prevents '.
           'such work.'),
       ),
       'nobranch' => array(
         'supports' => array('git', 'hg'),
         'help' => pht(
           'Normally, a new branch (git) or bookmark (hg) is created and then '.
           'the patch is applied and committed in the new branch/bookmark. '.
           'This flag cherry-picks the resultant commit onto the original '.
           'branch and deletes the temporary branch.'),
         'conflicts' => array(
           'update' => true,
         ),
       ),
       'force' => array(
         'help' => pht('Do not run any sanity checks.'),
       ),
       '*' => 'name',
     );
   }
 
   protected function didParseArguments() {
-    $source = null;
-    $requested = 0;
-    if ($this->getArgument('revision')) {
-      $source = self::SOURCE_REVISION;
-      $requested++;
-    }
-    if ($this->getArgument('diff')) {
-      $source = self::SOURCE_DIFF;
-      $requested++;
-    }
-    if ($this->getArgument('arcbundle')) {
-      $source = self::SOURCE_BUNDLE;
-      $requested++;
-    }
-    if ($this->getArgument('patch')) {
-      $source = self::SOURCE_PATCH;
-      $requested++;
-    }
+    $arguments = array(
+      'revision' => self::SOURCE_REVISION,
+      'diff' => self::SOURCE_DIFF,
+      'arcbundle' => self::SOURCE_BUNDLE,
+      'patch' => self::SOURCE_PATCH,
+      'name' => self::SOURCE_REVISION,
+    );
+
+    $sources = array();
+    foreach ($arguments as $key => $source_type) {
+      $value = $this->getArgument($key);
+      if (!$value) {
+        continue;
+      }
 
-    $use_revision_id = null;
-    if ($this->getArgument('name')) {
-      $namev = $this->getArgument('name');
-      if (count($namev) > 1) {
-        throw new ArcanistUsageException(
-          pht('Specify at most one revision name.'));
+      switch ($key) {
+        case 'revision':
+          $value = $this->normalizeRevisionID($value);
+          break;
+        case 'name':
+          if (count($value) > 1) {
+            throw new ArcanistUsageException(
+              pht('Specify at most one revision name.'));
+          }
+          $value = $this->normalizeRevisionID(head($value));
+          break;
       }
-      $source = self::SOURCE_REVISION;
-      $requested++;
 
-      $use_revision_id = $this->normalizeRevisionID(head($namev));
+      $sources[] = array(
+        $source_type,
+        $value,
+      );
     }
 
-    if ($requested === 0) {
+    if (!$sources) {
       throw new ArcanistUsageException(
         pht(
-          "Specify one of '%s', '%s' (to select the current changes attached ".
-          "to a Differential revision), '%s' (to select a specific, ".
-          "out-of-date diff or a diff which is not attached to a revision), ".
-          "'%s' or '%s' to choose a patch source.",
-          'D12345',
-          '--revision <revision_id>',
-          '--diff <diff_id>',
-          '--arcbundle <file>',
-          '--patch <file>'));
-    } else if ($requested > 1) {
+          'You must specify changes to apply to the working copy with '.
+          '"D12345", "--revision", "--diff", "--arcbundle", or "--patch".'));
+    }
+
+    if (count($sources) > 1) {
       throw new ArcanistUsageException(
         pht(
-          "Options '%s', '%s', '%s', '%s' and '%s' are not compatible. ".
-          "Choose exactly one patch source.",
-          'D12345',
-          '--revision',
-          '--diff',
-          '--arcbundle',
-          '--patch'));
+          'Options "D12345", "--revision", "--diff", "--arcbundle" and '.
+          '"--patch" are mutually exclusive. Choose exactly one patch '.
+          'source.'));
     }
 
-    $this->source = $source;
-    $this->sourceParam = nonempty(
-      $use_revision_id,
-      $this->getArgument($source));
+    $source = head($sources);
+
+    $this->source = $source[0];
+    $this->sourceParam = $source[1];
   }
 
   public function requiresConduit() {
     return ($this->getSource() != self::SOURCE_PATCH);
   }
 
   public function requiresRepositoryAPI() {
     return true;
   }
 
   public function requiresWorkingCopy() {
     return true;
   }
 
   private function getSource() {
     return $this->source;
   }
 
   private function getSourceParam() {
     return $this->sourceParam;
   }
 
   private function shouldCommit() {
     return !$this->getArgument('nocommit', false);
   }
 
   private function canBranch() {
     $repository_api = $this->getRepositoryAPI();
     return ($repository_api instanceof ArcanistGitAPI) ||
            ($repository_api instanceof ArcanistMercurialAPI);
   }
 
   private function shouldBranch() {
     $no_branch = $this->getArgument('nobranch', false);
     if ($no_branch) {
       return false;
     }
     return true;
   }
 
   private function getBranchName(ArcanistBundle $bundle) {
     $branch_name    = null;
     $repository_api = $this->getRepositoryAPI();
     $revision_id    = $bundle->getRevisionID();
     $base_name      = 'arcpatch';
     if ($revision_id) {
       $base_name .= "-D{$revision_id}";
     }
 
     $suffixes = array(null, '_1', '_2', '_3');
     foreach ($suffixes as $suffix) {
       $proposed_name = $base_name.$suffix;
 
       list($err) = $repository_api->execManualLocal(
         'rev-parse --verify %s',
         $proposed_name);
 
       // no error means git rev-parse found a branch
       if (!$err) {
         echo phutil_console_format(
           "%s\n",
           pht(
             'Branch name %s already exists; trying a new name.',
             $proposed_name));
         continue;
       } else {
         $branch_name = $proposed_name;
         break;
       }
     }
 
     if (!$branch_name) {
       throw new Exception(
         pht(
           'Arc was unable to automagically make a name for this patch. '.
           'Please clean up your working copy and try again.'));
     }
 
     return $branch_name;
   }
 
   private function getBookmarkName(ArcanistBundle $bundle) {
     $bookmark_name  = null;
     $repository_api = $this->getRepositoryAPI();
     $revision_id    = $bundle->getRevisionID();
     $base_name      = 'arcpatch';
     if ($revision_id) {
       $base_name .= "-D{$revision_id}";
     }
 
     $suffixes = array(null, '-1', '-2', '-3');
     foreach ($suffixes as $suffix) {
       $proposed_name = $base_name.$suffix;
 
       list($err) = $repository_api->execManualLocal(
         'log -r %s',
         hgsprintf('%s', $proposed_name));
 
       // no error means hg log found a bookmark
       if (!$err) {
         echo phutil_console_format(
           "%s\n",
           pht(
             'Bookmark name %s already exists; trying a new name.',
             $proposed_name));
         continue;
       } else {
         $bookmark_name = $proposed_name;
         break;
       }
     }
 
     if (!$bookmark_name) {
       throw new Exception(
         pht(
           'Arc was unable to automagically make a name for this patch. '.
           'Please clean up your working copy and try again.'));
     }
 
     return $bookmark_name;
   }
 
   private function createBranch(ArcanistBundle $bundle, $has_base_revision) {
     $repository_api = $this->getRepositoryAPI();
     if ($repository_api instanceof ArcanistGitAPI) {
       $branch_name = $this->getBranchName($bundle);
       $base_revision = $bundle->getBaseRevision();
 
       if ($base_revision && $has_base_revision) {
         $base_revision = $repository_api->getCanonicalRevisionName(
           $base_revision);
         $repository_api->execxLocal(
           'checkout -b %s %s',
           $branch_name,
           $base_revision);
       } else {
         $repository_api->execxLocal('checkout -b %s', $branch_name);
       }
 
       echo phutil_console_format(
         "%s\n",
         pht(
           'Created and checked out branch %s.',
           $branch_name));
     } else if ($repository_api instanceof ArcanistMercurialAPI) {
       $branch_name = $this->getBookmarkName($bundle);
       $base_revision = $bundle->getBaseRevision();
 
       if ($base_revision && $has_base_revision) {
         $base_revision = $repository_api->getCanonicalRevisionName(
           $base_revision);
 
         echo pht("Updating to the revision's base commit")."\n";
         $repository_api->execPassthru('update %s', $base_revision);
       }
 
       $repository_api->execxLocal('bookmark %s', $branch_name);
 
       echo phutil_console_format(
         "%s\n",
         pht(
           'Created and checked out bookmark %s.',
           $branch_name));
     }
 
     return $branch_name;
   }
 
   private function shouldApplyDependencies() {
     return !$this->getArgument('skip-dependencies', false);
   }
 
   private function shouldUpdateWorkingCopy() {
     return $this->getArgument('update', false);
   }
 
   private function updateWorkingCopy() {
     echo pht('Updating working copy...')."\n";
     $this->getRepositoryAPI()->updateWorkingCopy();
     echo pht('Done.')."\n";
   }
 
   public function run() {
     $source = $this->getSource();
     $param = $this->getSourceParam();
     try {
       switch ($source) {
         case self::SOURCE_PATCH:
           if ($param == '-') {
             $patch = @file_get_contents('php://stdin');
             if (!strlen($patch)) {
               throw new ArcanistUsageException(
                 pht('Failed to read patch from stdin!'));
             }
           } else {
             $patch = Filesystem::readFile($param);
           }
           $bundle = ArcanistBundle::newFromDiff($patch);
           break;
         case self::SOURCE_BUNDLE:
           $path = $this->getArgument('arcbundle');
           $bundle = ArcanistBundle::newFromArcBundle($path);
           break;
         case self::SOURCE_REVISION:
           $bundle = $this->loadRevisionBundleFromConduit(
             $this->getConduit(),
             $param);
           break;
         case self::SOURCE_DIFF:
           $bundle = $this->loadDiffBundleFromConduit(
             $this->getConduit(),
             $param);
           break;
       }
     } catch (ConduitClientException $ex) {
       if ($ex->getErrorCode() == 'ERR-INVALID-SESSION') {
         // Phabricator is not configured to allow anonymous access to
         // Differential.
         $this->authenticateConduit();
         return $this->run();
       } else {
         throw $ex;
       }
     }
 
     $try_encoding = nonempty($this->getArgument('encoding'), null);
     if (!$try_encoding) {
       if ($this->requiresConduit()) {
         try {
           $try_encoding = $this->getRepositoryEncoding();
         } catch (ConduitClientException $e) {
           $try_encoding = null;
         }
       }
     }
 
     if ($try_encoding) {
       $bundle->setEncoding($try_encoding);
     }
 
     $sanity_check = !$this->getArgument('force', false);
 
     // we should update the working copy before we do ANYTHING else to
     // the working copy
     if ($this->shouldUpdateWorkingCopy()) {
       $this->updateWorkingCopy();
     }
 
     if ($sanity_check) {
       $this->requireCleanWorkingCopy();
     }
 
     $repository_api = $this->getRepositoryAPI();
     $has_base_revision = $repository_api->hasLocalCommit(
       $bundle->getBaseRevision());
     if (!$has_base_revision) {
       if ($repository_api instanceof ArcanistGitAPI) {
         echo phutil_console_format(
           "<bg:blue>** %s **</bg> %s\n",
           pht('INFO'),
           pht('Base commit is not in local repository; trying to fetch.'));
         $repository_api->execManualLocal('fetch --quiet --all');
         $has_base_revision = $repository_api->hasLocalCommit(
           $bundle->getBaseRevision());
       }
     }
 
     if ($this->canBranch() &&
          ($this->shouldBranch() ||
          ($this->shouldCommit() && $has_base_revision))) {
 
       if ($repository_api instanceof ArcanistGitAPI) {
         $original_branch = $repository_api->getBranchName();
       } else if ($repository_api instanceof ArcanistMercurialAPI) {
         $original_branch = $repository_api->getActiveBookmark();
       }
 
       // If we weren't on a branch, then record the ref we'll return to
       // instead.
       if ($original_branch === null) {
         if ($repository_api instanceof ArcanistGitAPI) {
           $original_branch = $repository_api->getCanonicalRevisionName('HEAD');
         } else if ($repository_api instanceof ArcanistMercurialAPI) {
           $original_branch = $repository_api->getCanonicalRevisionName('.');
         }
       }
 
       $new_branch = $this->createBranch($bundle, $has_base_revision);
     }
     if (!$has_base_revision && $this->shouldApplyDependencies()) {
       $this->applyDependencies($bundle);
     }
 
     if ($sanity_check) {
       $this->sanityCheck($bundle);
     }
 
     if ($repository_api instanceof ArcanistSubversionAPI) {
       $patch_err = 0;
 
       $copies = array();
       $deletes = array();
       $patches = array();
       $propset = array();
       $adds = array();
       $symlinks = array();
 
       $changes = $bundle->getChanges();
       foreach ($changes as $change) {
         $type = $change->getType();
         $should_patch = true;
 
         $filetype = $change->getFileType();
         switch ($filetype) {
           case ArcanistDiffChangeType::FILE_SYMLINK:
             $should_patch = false;
             $symlinks[] = $change;
             break;
         }
 
         switch ($type) {
           case ArcanistDiffChangeType::TYPE_MOVE_AWAY:
           case ArcanistDiffChangeType::TYPE_MULTICOPY:
           case ArcanistDiffChangeType::TYPE_DELETE:
             $path = $change->getCurrentPath();
             $fpath = $repository_api->getPath($path);
             if (!@file_exists($fpath)) {
               $ok = phutil_console_confirm(
                 pht(
                   "Patch deletes file '%s', but the file does not exist in ".
                   "the working copy. Continue anyway?",
                   $path));
               if (!$ok) {
                 throw new ArcanistUserAbortException();
               }
             } else {
               $deletes[] = $change->getCurrentPath();
             }
             $should_patch = false;
             break;
           case ArcanistDiffChangeType::TYPE_COPY_HERE:
           case ArcanistDiffChangeType::TYPE_MOVE_HERE:
             $path = $change->getOldPath();
             $fpath = $repository_api->getPath($path);
             if (!@file_exists($fpath)) {
               $cpath = $change->getCurrentPath();
               if ($type == ArcanistDiffChangeType::TYPE_COPY_HERE) {
                 $verbs = pht('copies');
               } else {
                 $verbs = pht('moves');
               }
               $ok = phutil_console_confirm(
                 pht(
                   "Patch %s '%s' to '%s', but source path does not exist ".
                   "in the working copy. Continue anyway?",
                   $verbs,
                   $path,
                   $cpath));
               if (!$ok) {
                 throw new ArcanistUserAbortException();
               }
             } else {
               $copies[] = array(
                 $change->getOldPath(),
                 $change->getCurrentPath(),
               );
             }
             break;
           case ArcanistDiffChangeType::TYPE_ADD:
             $adds[] = $change->getCurrentPath();
             break;
         }
         if ($should_patch) {
           $cbundle = ArcanistBundle::newFromChanges(array($change));
           $patches[$change->getCurrentPath()] = $cbundle->toUnifiedDiff();
           $prop_old = $change->getOldProperties();
           $prop_new = $change->getNewProperties();
           $props = $prop_old + $prop_new;
           foreach ($props as $key => $ignored) {
             if (idx($prop_old, $key) !== idx($prop_new, $key)) {
               $propset[$change->getCurrentPath()][$key] = idx($prop_new, $key);
             }
           }
         }
       }
 
       // Before we start doing anything, create all the directories we're going
       // to add files to if they don't already exist.
       foreach ($copies as $copy) {
         list($src, $dst) = $copy;
         $this->createParentDirectoryOf($dst);
       }
 
       foreach ($patches as $path => $patch) {
         $this->createParentDirectoryOf($path);
       }
 
       foreach ($adds as $add) {
         $this->createParentDirectoryOf($add);
       }
 
       // TODO: The SVN patch workflow likely does not work on windows because
       // of the (cd ...) stuff.
 
       foreach ($copies as $copy) {
         list($src, $dst) = $copy;
         passthru(
           csprintf(
             '(cd %s; svn cp %s %s)',
             $repository_api->getPath(),
             ArcanistSubversionAPI::escapeFileNameForSVN($src),
             ArcanistSubversionAPI::escapeFileNameForSVN($dst)));
       }
 
       foreach ($deletes as $delete) {
         passthru(
           csprintf(
             '(cd %s; svn rm %s)',
             $repository_api->getPath(),
             ArcanistSubversionAPI::escapeFileNameForSVN($delete)));
       }
 
       foreach ($symlinks as $symlink) {
         $link_target = $symlink->getSymlinkTarget();
         $link_path = $symlink->getCurrentPath();
         switch ($symlink->getType()) {
           case ArcanistDiffChangeType::TYPE_ADD:
           case ArcanistDiffChangeType::TYPE_CHANGE:
           case ArcanistDiffChangeType::TYPE_MOVE_HERE:
           case ArcanistDiffChangeType::TYPE_COPY_HERE:
             execx(
               '(cd %s && ln -sf %s %s)',
               $repository_api->getPath(),
               $link_target,
               $link_path);
             break;
         }
       }
 
       foreach ($patches as $path => $patch) {
         $err = null;
         if ($patch) {
           $tmp = new TempFile();
           Filesystem::writeFile($tmp, $patch);
           passthru(
             csprintf(
               '(cd %s; patch -p0 < %s)',
               $repository_api->getPath(),
               $tmp),
             $err);
         } else {
           passthru(
             csprintf(
               '(cd %s; touch %s)',
               $repository_api->getPath(),
               $path),
             $err);
         }
         if ($err) {
           $patch_err = max($patch_err, $err);
         }
       }
 
       foreach ($adds as $add) {
         passthru(
           csprintf(
             '(cd %s; svn add %s)',
             $repository_api->getPath(),
             ArcanistSubversionAPI::escapeFileNameForSVN($add)));
       }
 
       foreach ($propset as $path => $changes) {
         foreach ($changes as $prop => $value) {
           if ($prop == 'unix:filemode') {
             // Setting this property also changes the file mode.
             $prop = 'svn:executable';
             $value = (octdec($value) & 0111 ? 'on' : null);
           }
           if ($value === null) {
             passthru(
               csprintf(
                 '(cd %s; svn propdel %s %s)',
                 $repository_api->getPath(),
                 $prop,
                 ArcanistSubversionAPI::escapeFileNameForSVN($path)));
           } else {
             passthru(
               csprintf(
                 '(cd %s; svn propset %s %s %s)',
                 $repository_api->getPath(),
                 $prop,
                 $value,
                 ArcanistSubversionAPI::escapeFileNameForSVN($path)));
           }
         }
       }
 
       if ($patch_err == 0) {
         echo phutil_console_format(
           "<bg:green>** %s **</bg> %s\n",
           pht('OKAY'),
           pht('Successfully applied patch to the working copy.'));
       } else {
         echo phutil_console_format(
           "\n\n<bg:yellow>** %s **</bg> %s\n",
           pht('WARNING'),
           pht(
             "Some hunks could not be applied cleanly by the unix '%s' ".
             "utility. Your working copy may be different from the revision's ".
             "base, or you may be in the wrong subdirectory. You can export ".
             "the raw patch file using '%s', and then try to apply it by ".
             "fiddling with options to '%s' (particularly, %s), or manually. ".
             "The output above, from '%s', may be helpful in ".
             "figuring out what went wrong.",
             'patch',
             'arc export --unified',
             'patch',
             '-p',
             'patch'));
       }
 
       return $patch_err;
     } else if ($repository_api instanceof ArcanistGitAPI) {
 
       $patchfile = new TempFile();
       Filesystem::writeFile($patchfile, $bundle->toGitPatch());
 
       $passthru = new PhutilExecPassthru(
         'git apply --whitespace nowarn --index --reject -- %s',
         $patchfile);
       $passthru->setCWD($repository_api->getPath());
       $err = $passthru->execute();
 
       if ($err) {
         echo phutil_console_format(
           "\n<bg:red>** %s **</bg>\n",
           pht('Patch Failed!'));
 
         // NOTE: Git patches may fail if they change the case of a filename
         // (for instance, from 'example.c' to 'Example.c'). As of now, Git
         // can not apply these patches on case-insensitive filesystems and
         // there is no way to build a patch which works.
 
         throw new ArcanistUsageException(pht('Unable to apply patch!'));
       }
 
       // in case there were any submodule changes involved
       $repository_api->execPassthru('submodule update --init --recursive');
 
       if ($this->shouldCommit()) {
         if ($bundle->getFullAuthor()) {
           $author_cmd = csprintf('--author=%s', $bundle->getFullAuthor());
         } else {
           $author_cmd = '';
         }
 
         $commit_message = $this->getCommitMessage($bundle);
         $future = $repository_api->execFutureLocal(
           'commit -a %C -F - --no-verify',
           $author_cmd);
         $future->write($commit_message);
         $future->resolvex();
         $verb = pht('committed');
       } else {
         $verb = pht('applied');
       }
 
       if ($this->canBranch() &&
           !$this->shouldBranch() &&
           $this->shouldCommit() && $has_base_revision) {
         $repository_api->execxLocal('checkout %s', $original_branch);
         $ex = null;
         try {
           $repository_api->execxLocal('cherry-pick %s', $new_branch);
         } catch (Exception $ex) {
           // do nothing
         }
         $repository_api->execxLocal('branch -D %s', $new_branch);
         if ($ex) {
           echo phutil_console_format(
             "\n<bg:red>** %s**</bg>\n",
             pht('Cherry Pick Failed!'));
           throw $ex;
         }
       }
 
       echo phutil_console_format(
         "<bg:green>** %s **</bg> %s\n",
         pht('OKAY'),
         pht('Successfully %s patch.', $verb));
     } else if ($repository_api instanceof ArcanistMercurialAPI) {
       $future = $repository_api->execFutureLocal('import --no-commit -');
       $future->write($bundle->toGitPatch());
 
       try {
         $future->resolvex();
       } catch (CommandException $ex) {
         echo phutil_console_format(
           "\n<bg:red>** %s **</bg>\n",
           pht('Patch Failed!'));
         $stderr = $ex->getStderr();
         if (preg_match('/case-folding collision/', $stderr)) {
           echo phutil_console_wrap(
             phutil_console_format(
               "\n<bg:yellow>** %s **</bg> %s\n",
               pht('WARNING'),
               pht(
                 "This patch may have failed because it attempts to change ".
                 "the case of a filename (for instance, from '%s' to '%s'). ".
                 "Mercurial cannot apply patches like this on case-insensitive ".
                 "filesystems. You must apply this patch manually.",
                 'example.c',
                 'Example.c')));
         }
         throw $ex;
       }
 
       if ($this->shouldCommit()) {
         $author = coalesce($bundle->getFullAuthor(), $bundle->getAuthorName());
         if ($author !== null) {
           $author_cmd = csprintf('-u %s', $author);
         } else {
           $author_cmd = '';
         }
 
         $commit_message = $this->getCommitMessage($bundle);
         $future = $repository_api->execFutureLocal(
           'commit %C -l -',
           $author_cmd);
         $future->write($commit_message);
         $future->resolvex();
 
         if (!$this->shouldBranch() && $has_base_revision) {
           $original_rev = $repository_api->getCanonicalRevisionName(
             $original_branch);
           $current_parent = $repository_api->getCanonicalRevisionName(
             hgsprintf('%s^', $new_branch));
 
           $err = 0;
           if ($original_rev != $current_parent) {
             list($err) = $repository_api->execManualLocal(
               'rebase --dest %s --rev %s',
               hgsprintf('%s', $original_branch),
               hgsprintf('%s', $new_branch));
           }
 
           $repository_api->execxLocal('bookmark --delete %s', $new_branch);
           if ($err) {
             $repository_api->execManualLocal('rebase --abort');
             throw new ArcanistUsageException(
               phutil_console_format(
                 "\n<bg:red>** %s**</bg>\n",
                 pht('Rebase onto %s failed!', $original_branch)));
           }
         }
 
         $verb = pht('committed');
       } else {
         $verb = pht('applied');
       }
 
       echo phutil_console_format(
         "<bg:green>** %s **</bg> %s\n",
         pht('OKAY'),
         pht('Successfully %s patch.', $verb));
     } else {
       throw new Exception(pht('Unknown version control system.'));
     }
 
     return 0;
   }
 
   private function getCommitMessage(ArcanistBundle $bundle) {
     $revision_id    = $bundle->getRevisionID();
     $commit_message = null;
     $prompt_message = null;
 
     // if we have a revision id the commit message is in differential
 
     // TODO: See T848 for the authenticated stuff.
     if ($revision_id && $this->isConduitAuthenticated()) {
 
       $conduit        = $this->getConduit();
       $commit_message = $conduit->callMethodSynchronous(
         'differential.getcommitmessage',
         array(
           'revision_id' => $revision_id,
         ));
       $prompt_message = pht(
         '  Note arcanist failed to load the commit message '.
         'from differential for revision %s.',
         "D{$revision_id}");
     }
 
     // no revision id or failed to fetch commit message so get it from the
     // user on the command line
     if (!$commit_message) {
       $template = sprintf(
         "\n\n# %s%s\n",
         pht(
           'Enter a commit message for this patch. If you just want to apply '.
           'the patch to the working copy without committing, re-run arc patch '.
           'with the %s flag.',
           '--nocommit'),
         $prompt_message);
 
       $commit_message = $this->newInteractiveEditor($template)
         ->setName('arcanist-patch-commit-message')
         ->editInteractively();
 
       $commit_message = ArcanistCommentRemover::removeComments($commit_message);
       if (!strlen(trim($commit_message))) {
         throw new ArcanistUserAbortException();
       }
     }
 
     return $commit_message;
   }
 
   protected function getShellCompletions(array $argv) {
     // TODO: Pull open diffs from 'arc list'?
     return array('ARGUMENT');
   }
 
   private function applyDependencies(ArcanistBundle $bundle) {
     // check for (and automagically apply on the user's be-hest) any revisions
     // this patch depends on
     $graph = $this->buildDependencyGraph($bundle);
     if ($graph) {
       $start_phid = $graph->getStartPHID();
       $cycle_phids = $graph->detectCycles($start_phid);
       if ($cycle_phids) {
         $phids = array_keys($graph->getNodes());
         $issue = pht(
           'The dependencies for this patch have a cycle. Applying them '.
           'is not guaranteed to work. Continue anyway?');
         $okay = phutil_console_confirm($issue, true);
       } else {
         $phids = $graph->getTopographicallySortedNodes();
         $phids = array_reverse($phids);
         $okay = true;
       }
 
       if (!$okay) {
         return;
       }
 
       $dep_on_revs = $this->getConduit()->callMethodSynchronous(
         'differential.query',
         array(
           'phids' => $phids,
         ));
       $revs = array();
       foreach ($dep_on_revs as $dep_on_rev) {
         $revs[$dep_on_rev['phid']] = 'D'.$dep_on_rev['id'];
       }
       // order them in case we got a topological sort earlier
       $revs = array_select_keys($revs, $phids);
       if (!empty($revs)) {
         $base_args = array(
           '--force',
           '--skip-dependencies',
           '--nobranch',
         );
         if (!$this->shouldCommit()) {
           $base_args[] = '--nocommit';
         }
 
         foreach ($revs as $phid => $diff_id) {
           // we'll apply this, the actual patch, later
           // this should be the last in the list
           if ($phid == $start_phid) {
             continue;
           }
           $args = $base_args;
           $args[] = $diff_id;
           $apply_workflow = $this->buildChildWorkflow(
             'patch',
             $args);
           $apply_workflow->run();
         }
       }
     }
   }
 
   /**
    * Do the best we can to prevent PEBKAC and id10t issues.
    */
   private function sanityCheck(ArcanistBundle $bundle) {
     $repository_api = $this->getRepositoryAPI();
 
     // Check to see if the bundle's base revision matches the working copy
     // base revision
     if ($repository_api->supportsLocalCommits()) {
       $bundle_base_rev = $bundle->getBaseRevision();
       if (empty($bundle_base_rev)) {
         // this means $source is SOURCE_PATCH || SOURCE_BUNDLE w/ $version < 2
         // they don't have a base rev so just do nothing
         $commit_exists = true;
       } else {
         $commit_exists =
           $repository_api->hasLocalCommit($bundle_base_rev);
       }
       if (!$commit_exists) {
         // we have a problem...! lots of work because we need to ask
         // differential for revision information for these base revisions
         // to improve our error message.
         $bundle_base_rev_str = null;
         $source_base_rev     = $repository_api->getWorkingCopyRevision();
         $source_base_rev_str = null;
 
         if ($repository_api instanceof ArcanistGitAPI) {
           $hash_type = ArcanistDifferentialRevisionHash::HASH_GIT_COMMIT;
         } else if ($repository_api instanceof ArcanistMercurialAPI) {
           $hash_type = ArcanistDifferentialRevisionHash::HASH_MERCURIAL_COMMIT;
         } else {
           $hash_type = null;
         }
 
         if ($hash_type) {
           // 2 round trips because even though we could send off one query
           // we wouldn't be able to tell which revisions were for which hash
           $hash = array($hash_type, $bundle_base_rev);
           $bundle_revision = $this->loadRevisionFromHash($hash);
           $hash = array($hash_type, $source_base_rev);
           $source_revision = $this->loadRevisionFromHash($hash);
 
           if ($bundle_revision) {
             $bundle_base_rev_str = $bundle_base_rev.
               ' \ D'.$bundle_revision['id'];
           }
           if ($source_revision) {
             $source_base_rev_str = $source_base_rev.
               ' \ D'.$source_revision['id'];
           }
         }
         $bundle_base_rev_str = nonempty(
           $bundle_base_rev_str,
           $bundle_base_rev);
         $source_base_rev_str = nonempty(
           $source_base_rev_str,
           $source_base_rev);
 
         $ok = phutil_console_confirm(
           pht(
             'This diff is against commit %s, but the commit is nowhere '.
             'in the working copy. Try to apply it against the current '.
             'working copy state? (%s)',
             $bundle_base_rev_str,
             $source_base_rev_str),
           $default_no = false);
         if (!$ok) {
           throw new ArcanistUserAbortException();
         }
       }
     }
   }
 
   /**
    * Create parent directories one at a time, since we need to "svn add" each
    * one. (Technically we could "svn add" just the topmost new directory.)
    */
   private function createParentDirectoryOf($path) {
     $repository_api = $this->getRepositoryAPI();
     $dir = dirname($path);
     if (Filesystem::pathExists($dir)) {
       return;
     } else {
       // Make sure the parent directory exists before we make this one.
       $this->createParentDirectoryOf($dir);
       execx(
         '(cd %s && mkdir %s)',
         $repository_api->getPath(),
         $dir);
       passthru(
         csprintf(
           '(cd %s && svn add %s)',
           $repository_api->getPath(),
           $dir));
     }
   }
 
   private function loadRevisionFromHash($hash) {
     // TODO -- de-hack this as permissions become more clear with things
     // like T848 (add scope to OAuth)
     if (!$this->isConduitAuthenticated()) {
       return null;
     }
 
     $conduit = $this->getConduit();
 
     $revisions = $conduit->callMethodSynchronous(
       'differential.query',
       array(
         'commitHashes' => array($hash),
       ));
 
 
     // grab the latest closed revision only
     $found_revision = null;
     $revisions = isort($revisions, 'dateModified');
     foreach ($revisions as $revision) {
       if ($revision['status'] == ArcanistDifferentialRevisionStatus::CLOSED) {
         $found_revision = $revision;
       }
     }
     return $found_revision;
   }
 
   private function buildDependencyGraph(ArcanistBundle $bundle) {
     $graph = null;
     if ($this->getRepositoryAPI() instanceof ArcanistSubversionAPI) {
       return $graph;
     }
     $revision_id = $bundle->getRevisionID();
     if ($revision_id) {
       $revisions = $this->getConduit()->callMethodSynchronous(
         'differential.query',
         array(
           'ids' => array($revision_id),
         ));
       if ($revisions) {
         $revision = head($revisions);
         $rev_auxiliary = idx($revision, 'auxiliary', array());
         $phids = idx($rev_auxiliary, 'phabricator:depends-on', array());
         if ($phids) {
           $revision_phid = $revision['phid'];
           $graph = id(new ArcanistDifferentialDependencyGraph())
             ->setConduit($this->getConduit())
             ->setRepositoryAPI($this->getRepositoryAPI())
             ->setStartPHID($revision_phid)
             ->addNodes(array($revision_phid => $phids))
             ->loadGraph();
         }
       }
     }
 
     return $graph;
   }
 
 }