Yell at developers if they don't replace the default revision title with thier new revision title.

Summary: Same as the title

Test Plan: Will test locally by running arc diff

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin, AnhNhan, starruler

Maniphest Tasks: T2663

Differential Revision: https://secure.phabricator.com/D5297

src/applications/differential/conduit/ConduitAPI_differential_getcommitmessage_Method.php

@@ -102,7 +102,8 @@ final class ConduitAPI_differential_getcommitmessage_Method
       $label = $field->renderLabelForCommitMessage();
       if (!strlen($value)) {
         if ($field_key === 'title') {
-          $commit_message[] = '<<Enter Revision Title>>';
+          $commit_message[] =
+            DifferentialTitleFieldSpecification::getDefaultRevisionTitle();
         } else {
           if ($field->shouldAppearOnCommitMessageTemplate() && $is_edit) {
             $commit_message[] = $label.': ';

src/applications/differential/field/specification/DifferentialTitleFieldSpecification.php

@@ -41,7 +41,16 @@ final class DifferentialTitleFieldSpecification
     if (!strlen($this->title)) {
       $this->error = 'Required';
       throw new DifferentialFieldValidationException(
-        "You must provide a title.");
+        "You must provide a revision title in the first line ".
+        "of your commit message.");
+    }
+
+    if (preg_match('/^<<.*>>$/', $this->title)) {
+      $default_title = self::getDefaultRevisionTitle();
+      $this->error = 'Required';
+      throw new DifferentialFieldValidationException(
+        "Replace the line '{$default_title}' with a revision title ".
+        "that describes the change.");
     }
   }
 
@@ -86,6 +95,10 @@ final class DifferentialTitleFieldSpecification
     return 'wide pri';
   }
 
+  public static function getDefaultRevisionTitle() {
+    return '<<Replace this line with your Revision Title>>';
+  }
+
   public function renderValueForRevisionList(DifferentialRevision $revision) {
     return phutil_tag(
       'a',