Index: src/__phutil_library_map__.php
===================================================================
--- src/__phutil_library_map__.php
+++ src/__phutil_library_map__.php
@@ -69,6 +69,7 @@
     'LinesOfALargeFile' => 'filesystem/linesofalarge/LinesOfALargeFile.php',
     'LinesOfALargeFileTestCase' => 'filesystem/linesofalarge/__tests__/LinesOfALargeFileTestCase.php',
     'MFilterTestHelper' => 'utils/__tests__/MFilterTestHelper.php',
+    'PHPASTParserTestCase' => 'parser/xhpast/__tests__/PHPASTParserTestCase.php',
     'PhageAgentBootloader' => 'phage/bootloader/PhageAgentBootloader.php',
     'PhageAgentTestCase' => 'phage/__tests__/PhageAgentTestCase.php',
     'PhagePHPAgent' => 'phage/agent/PhagePHPAgent.php',
@@ -476,6 +477,7 @@
     'LinesOfALargeExecFutureTestCase' => 'PhutilTestCase',
     'LinesOfALargeFile' => 'LinesOfALarge',
     'LinesOfALargeFileTestCase' => 'PhutilTestCase',
+    'PHPASTParserTestCase' => 'PhutilTestCase',
     'PhageAgentTestCase' => 'PhutilTestCase',
     'PhagePHPAgentBootloader' => 'PhageAgentBootloader',
     'PhutilAWSEC2Future' => 'PhutilAWSFuture',
Index: src/parser/xhpast/__tests__/PHPASTParserTestCase.php
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/PHPASTParserTestCase.php
@@ -0,0 +1,131 @@
+<?php
+
+final class PHPASTParserTestCase extends PhutilTestCase {
+
+  public function testParser() {
+    if (!xhpast_is_available()) {
+      $this->assertSkipped(pht('xhpast is not built or not up to date.'));
+    }
+
+    $dir = dirname(__FILE__).'/data/';
+    foreach (Filesystem::listDirectory($dir) as $file) {
+      if (preg_match('/\.test$/', $file)) {
+        $this->executeParserTest($file, Filesystem::readFile($dir.$file));
+      }
+    }
+  }
+
+  private function executeParserTest($name, $data) {
+    $data = explode("\n", $data, 2);
+    if (count($data) !== 2) {
+      throw new Exception(
+        pht('Expected multiple lines in parser test file "%s".', $name));
+    }
+
+    $head = head($data);
+    $body = last($data);
+
+    if (!preg_match('/^#/', $head)) {
+      throw new Exception(
+        pht(
+          'Expected first line of parser test file "%s" to begin with "#" '.
+          'and specify test options.',
+          $name));
+    }
+
+    $head = preg_replace('/^#\s*/', '', $head);
+
+    $options_parser = new PhutilSimpleOptions();
+    $options = $options_parser->parse($head);
+
+    $type = null;
+    foreach ($options as $key => $value) {
+      switch ($key) {
+        case 'pass':
+        case 'fail-syntax':
+        case 'fail-parse':
+          if ($type !== null) {
+            throw new Exception(
+              pht(
+                'Test file "%s" unexpectedly specifies multiple expected ',
+                'test outcomes.',
+                $name));
+          }
+          $type = $key;
+          break;
+        default:
+          throw new Exception(
+            pht(
+              'Test file "%s" has unknown option "%s" in its options '.
+              'string.',
+              $name,
+              $key));
+      }
+    }
+
+    if ($type === null) {
+      throw new Exception(
+        pht(
+          'Test file "%s" does not specify a test result (like "pass") in '.
+          'its options string.',
+          $name));
+    }
+
+    $future = xhpast_get_parser_future($body);
+    list($err, $stdout, $stderr) = $future->resolve();
+
+    switch ($type) {
+      case 'pass':
+      case 'fail-parse':
+        $this->assertEqual(0, $err, pht('Exit code for "%s".', $name));
+
+        $expect_name = preg_replace('/\.test$/', '.expect', $name);
+
+        $dir = dirname(__FILE__).'/data/';
+        $expect = Filesystem::readFile($dir.$expect_name);
+
+        $expect = json_decode($expect, true);
+        if (!is_array($expect)) {
+          throw new Exception(
+            pht(
+              'Test ".expect" file "%s" for test "%s" is not valid JSON.',
+              $expect_name,
+              $name));
+        }
+
+        $stdout = json_decode($stdout, true);
+        if (!is_array($stdout)) {
+          throw new Exception(
+            pht(
+              'Output for test file "%s" is not valid JSON.',
+              $name));
+        }
+
+        $json = new PhutilJSON();
+
+        $expect_nice = $json->encodeFormatted($expect);
+        $stdout_nice = $json->encodeFormatted($stdout);
+
+        if ($type == 'pass') {
+          $this->assertEqual(
+            $expect_nice,
+            $stdout_nice,
+            pht('Parser output for "%s".', $name));
+        } else {
+          $this->assertEqual(
+            false,
+            ($expect_nice == $stdout_nice),
+            pht('Expected parser to parse "%s" incorrectly.', $name));
+        }
+        break;
+      case 'fail-syntax':
+        $this->assertEqual(1, $err, pht('Exit code for "%s".', $name));
+        $this->assertEqual(
+          true,
+          (bool)preg_match('/syntax error/', $stderr),
+          pht('Expect "syntax error" in stderr or "%s".', $name));
+        break;
+    }
+  }
+
+}
Index: src/parser/xhpast/__tests__/data/base-fail-parse.php.expect
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/data/base-fail-parse.php.expect
@@ -0,0 +1,4 @@
+{
+  "tree"   : [],
+  "stream" : []
+}
Index: src/parser/xhpast/__tests__/data/base-fail-parse.php.test
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/data/base-fail-parse.php.test
@@ -0,0 +1,2 @@
+# fail-parse
+<?php
Index: src/parser/xhpast/__tests__/data/base-fail-syntax.php.test
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/data/base-fail-syntax.php.test
@@ -0,0 +1,2 @@
+# fail-syntax
+<?php )
Index: src/parser/xhpast/__tests__/data/base-pass.php.expect
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/data/base-pass.php.expect
@@ -0,0 +1,27 @@
+{
+  "tree"   : [
+    9000,
+    0,
+    0,
+    [
+      [
+        9006,
+        0,
+        0,
+        [
+          [
+            9007,
+            0,
+            0
+          ]
+        ]
+      ]
+    ]
+  ],
+  "stream" : [
+    [
+      371,
+      6
+    ]
+  ]
+}
Index: src/parser/xhpast/__tests__/data/base-pass.php.test
===================================================================
--- /dev/null
+++ src/parser/xhpast/__tests__/data/base-pass.php.test
@@ -0,0 +1,2 @@
+# pass
+<?php