Make sure auditors are attached to commits on new pathways

Companion change to D19022 for commits. Mentioning and subscribing to commits
can load them without audit data.

src/applications/audit/editor/PhabricatorAuditEditor.php

@@ -490,6 +490,8 @@ final class PhabricatorAuditEditor
   }
 
   protected function getMailTo(PhabricatorLiskDAO $object) {
+    $this->requireAuditors($object);
+
     $phids = array();
 
     if ($object->getAuthorPHID()) {
@@ -514,6 +516,8 @@ final class PhabricatorAuditEditor
   }
 
   protected function newMailUnexpandablePHIDs(PhabricatorLiskDAO $object) {
+    $this->requireAuditors($object);
+
     $phids = array();
 
     foreach ($object->getAudits() as $auditor) {
@@ -856,4 +860,24 @@ final class PhabricatorAuditEditor
       ->executeOne();
   }
 
+  private function requireAuditors(PhabricatorRepositoryCommit $commit) {
+    if ($commit->hasAttachedAudits()) {
+      return;
+    }
+
+    $with_auditors = id(new DiffusionCommitQuery())
+      ->setViewer($this->getActor())
+      ->needAuditRequests(true)
+      ->withPHIDs(array($commit->getPHID()))
+      ->executeOne();
+    if (!$with_auditors) {
+      throw new Exception(
+        pht(
+          'Failed to reload commit ("%s").',
+          $commit->getPHID()));
+    }
+
+    $commit->attachAudits($with_auditors->getAudits());
+  }
+
 }

src/applications/repository/storage/PhabricatorRepositoryCommit.php

@@ -183,6 +183,10 @@ final class PhabricatorRepositoryCommit
     return $this->assertAttached($this->audits);
   }
 
+  public function hasAttachedAudits() {
+    return ($this->audits !== self::ATTACHABLE);
+  }
+
   public function loadAndAttachAuditAuthority(
     PhabricatorUser $viewer,
     $actor_phid = null) {