Add "Is merge commit?" to commit fields in Herald

Summary: Fixes T5788. We already have this as a pre-commit field, add it as a post-commit field too.

Test Plan: Ran this rule on a merge commit. Also ran it on a non-merge commit. Both got the correct value.

Reviewers: avivey, chad

Reviewed By: avivey, chad

Subscribers: avivey

Maniphest Tasks: T5788

Differential Revision: https://secure.phabricator.com/D14685

src/__phutil_library_map__.php

···
     'DiffusionCommitHeraldFieldGroup' => 'applications/diffusion/herald/DiffusionCommitHeraldFieldGroup.php',
     'DiffusionCommitHookEngine' => 'applications/diffusion/engine/DiffusionCommitHookEngine.php',
     'DiffusionCommitHookRejectException' => 'applications/diffusion/exception/DiffusionCommitHookRejectException.php',
+    'DiffusionCommitMergeHeraldField' => 'applications/diffusion/herald/DiffusionCommitMergeHeraldField.php',
     'DiffusionCommitMessageHeraldField' => 'applications/diffusion/herald/DiffusionCommitMessageHeraldField.php',
     'DiffusionCommitPackageAuditHeraldField' => 'applications/diffusion/herald/DiffusionCommitPackageAuditHeraldField.php',
     'DiffusionCommitPackageHeraldField' => 'applications/diffusion/herald/DiffusionCommitPackageHeraldField.php',
···
     'DiffusionCommitHeraldFieldGroup' => 'HeraldFieldGroup',
     'DiffusionCommitHookEngine' => 'Phobject',
     'DiffusionCommitHookRejectException' => 'Exception',
+    'DiffusionCommitMergeHeraldField' => 'DiffusionCommitHeraldField',
     'DiffusionCommitMessageHeraldField' => 'DiffusionCommitHeraldField',
     'DiffusionCommitPackageAuditHeraldField' => 'DiffusionCommitHeraldField',
     'DiffusionCommitPackageHeraldField' => 'DiffusionCommitHeraldField',

src/applications/diffusion/herald/DiffusionCommitMergeHeraldField.php

···
+<?php
+
+final class DiffusionCommitMergeHeraldField
+  extends DiffusionCommitHeraldField {
+
+  const FIELDCONST = 'diffusion.commit.merge';
+
+  public function getHeraldFieldName() {
+    return pht('Is merge commit');
+  }
+
+  public function getHeraldFieldValue($object) {
+    return $this->getAdapter()->loadIsMergeCommit();
+  }
+
+  protected function getHeraldFieldStandardType() {
+    return HeraldField::STANDARD_BOOL;
+  }
+
+}

src/applications/diffusion/herald/HeraldCommitAdapter.php

···
   }
 
   private function loadCommitDiff() {
-    $drequest = DiffusionRequest::newFromDictionary(
-      array(
-        'user' => PhabricatorUser::getOmnipotentUser(),
-        'repository' => $this->repository,
-        'commit' => $this->commit->getCommitIdentifier(),
-      ));
-
     $byte_limit = self::getEnormousByteLimit();
 
-    $raw = DiffusionQuery::callConduitWithDiffusionRequest(
-      PhabricatorUser::getOmnipotentUser(),
-      $drequest,
+    $raw = $this->callConduit(
       'diffusion.rawdiffquery',
       array(
         'commit' => $this->commit->getCommitIdentifier(),
···
     return $result;
   }
 
+  public function loadIsMergeCommit() {
+    $parents = $this->callConduit(
+      'diffusion.commitparentsquery',
+      array(
+        'commit' => $this->getObject()->getCommitIdentifier(),
+      ));
+
+    return (count($parents) > 1);
+  }
+
+  private function callConduit($method, array $params) {
+    $viewer = PhabricatorUser::getOmnipotentUser();
+
+    $drequest = DiffusionRequest::newFromDictionary(
+      array(
+        'user' => $viewer,
+        'repository' => $this->repository,
+        'commit' => $this->commit->getCommitIdentifier(),
+      ));
+
+    return DiffusionQuery::callConduitWithDiffusionRequest(
+      $viewer,
+      $drequest,
+      $method,
+      $params);
+  }
 
 /* -(  HarbormasterBuildableAdapterInterface  )------------------------------ */