Improve the ArcanistInfrastructureTestCase unit tests

Summary:
Improve the `ArcanistInfrastructureTestCase` unit tests such that they will fail if any of the following conditions are satisfied:

- A symbol referenced in the `__phutil_library_map__.php` file no longer exists.
- A symbol exists in the library but is not referenced within the `__phutil_library_map__.php` file.
- A symbol extends from a different parent symbol than that declared in the `__phutil_library_map.php` file.

Test Plan: See D9824

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9826

src/__tests__/ArcanistInfrastructureTestCase.php

@@ -1,6 +1,7 @@
 <?php
 
 final class ArcanistInfrastructureTestCase extends ArcanistTestCase {
+
   /**
    * This is more of an acceptance test case instead of a unit test. It verifies
    * that all symbols can be loaded correctly. It can catch problems like
@@ -10,4 +11,27 @@ final class ArcanistInfrastructureTestCase extends ArcanistTestCase {
     id(new PhutilSymbolLoader())->selectAndLoadSymbols();
     $this->assertTrue(true);
   }
+
+  /**
+   * This is more of an acceptance test case instead of a unit test. It verifies
+   * that all the library map is up-to-date.
+   */
+  public function testLibraryMap() {
+    $root = phutil_get_library_root('arcanist');
+
+    $new_library_map = id(new PhutilLibraryMapBuilder($root))
+      ->setQuiet(true)
+      ->setDryRun(true)
+      ->buildMap();
+
+    $bootloader = PhutilBootloader::getInstance();
+    $old_library_map = $bootloader->getLibraryMap('arcanist');
+    unset($old_library_map[PhutilLibraryMapBuilder::LIBRARY_MAP_VERSION_KEY]);
+
+    $this->assertEqual(
+      $new_library_map,
+      $old_library_map,
+      'The library map does not appear to be up-to-date. Try '.
+      'rebuilding the map with `arc liberate`.');
+  }
 }