Automatically support "Add Projects" in Herald for all relevant objects

Summary: Ref T7849. If the adapted object implements `PhabricatorProjectInterface`, support the ADD_PROJECTS action.

Test Plan:
  - Wrote a Differential rule with "Add Projects".
  - Updated a revision.
  - Got projects added.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7849

Differential Revision: https://secure.phabricator.com/D12504

src/applications/herald/adapter/HeraldAdapter.php

@@ -244,7 +244,7 @@ abstract class HeraldAdapter {
   }
 
   protected function newTransaction() {
-    $object = $this->getObject();
+    $object = $this->newObject();
 
     if (!($object instanceof PhabricatorApplicationTransactionInterface)) {
       throw new Exception(
@@ -258,8 +258,6 @@ abstract class HeraldAdapter {
   }
 
 
-
-
   /**
    * NOTE: You generally should not override this; it exists to support legacy
    * adapters which had hard-coded content types.
@@ -273,6 +271,26 @@ abstract class HeraldAdapter {
   abstract public function getAdapterApplicationClass();
   abstract public function getObject();
 
+
+  /**
+   * Return a new characteristic object for this adapter.
+   *
+   * The adapter will use this object to test for interfaces, generate
+   * transactions, and interact with custom fields.
+   *
+   * Adapters must return an object from this method to enable custom
+   * field rules and various implicit actions.
+   *
+   * Normally, you'll return an empty version of the adapted object:
+   *
+   *   return new ApplicationObject();
+   *
+   * @return null|object Template object.
+   */
+  protected function newObject() {
+    return null;
+  }
+
   public function supportsRuleType($rule_type) {
     return false;
   }
@@ -771,7 +789,19 @@ abstract class HeraldAdapter {
 
   public function getActions($rule_type) {
     $custom_actions = $this->getCustomActionsForRuleType($rule_type);
-    return mpull($custom_actions, 'getActionKey');
+    $custom_actions = mpull($custom_actions, 'getActionKey');
+
+    $actions = $custom_actions;
+
+    $object = $this->newObject();
+
+    if (($object instanceof PhabricatorProjectInterface)) {
+      if ($rule_type == HeraldRuleTypeConfig::RULE_TYPE_GLOBAL) {
+        $actions[] = self::ACTION_ADD_PROJECTS;
+      }
+    }
+
+    return $actions;
   }
 
   public function getActionNameMap($rule_type) {
@@ -1291,27 +1321,6 @@ abstract class HeraldAdapter {
 /* -(  Custom Field Integration  )------------------------------------------- */
 
 
-  /**
-   * Return an object which custom fields can be generated from while editing
-   * rules. Adapters must return an object from this method to enable custom
-   * field rules.
-   *
-   * Normally, you'll return an empty version of the adapted object, assuming
-   * it implements @{interface:PhabricatorCustomFieldInterface}:
-   *
-   *   return new ApplicationObject();
-   *
-   * This is normally the only adapter method you need to override to enable
-   * Herald rules to run against custom fields.
-   *
-   * @return null|PhabricatorCustomFieldInterface Template object.
-   * @task customfield
-   */
-  protected function getCustomFieldTemplateObject() {
-    return null;
-  }
-
-
   /**
    * Returns the prefix used to namespace Herald fields which are based on
    * custom fields.
@@ -1363,8 +1372,8 @@ abstract class HeraldAdapter {
       $this->customFields = null;
 
 
-      $template_object = $this->getCustomFieldTemplateObject();
-      if ($template_object) {
+      $template_object = $this->newObject();
+      if ($template_object instanceof PhabricatorCustomFieldInterface) {
         $object = $this->getObject();
         if (!$object) {
           $object = $template_object;

src/applications/herald/adapter/HeraldCommitAdapter.php

@@ -26,6 +26,10 @@ final class HeraldCommitAdapter extends HeraldAdapter {
     return 'PhabricatorDiffusionApplication';
   }
 
+  public function newObject() {
+    return new PhabricatorRepositoryCommit();
+  }
+
   public function getObject() {
     return $this->commit;
   }

src/applications/herald/adapter/HeraldDifferentialRevisionAdapter.php

@@ -24,6 +24,10 @@ final class HeraldDifferentialRevisionAdapter
     return 'PhabricatorDifferentialApplication';
   }
 
+  public function newObject() {
+    return new DifferentialRevision();
+  }
+
   public function getObject() {
     return $this->revision;
   }

src/applications/herald/adapter/HeraldManiphestTaskAdapter.php

@@ -6,6 +6,10 @@ final class HeraldManiphestTaskAdapter extends HeraldAdapter {
   private $ccPHIDs = array();
   private $assignPHID;
 
+  protected function newObject() {
+    return new ManiphestTask();
+  }
+
   public function getAdapterApplicationClass() {
     return 'PhabricatorManiphestApplication';
   }
@@ -90,7 +94,6 @@ final class HeraldManiphestTaskAdapter extends HeraldAdapter {
             self::ACTION_ADD_CC,
             self::ACTION_EMAIL,
             self::ACTION_ASSIGN_TASK,
-            self::ACTION_ADD_PROJECTS,
             self::ACTION_NOTHING,
           ),
           parent::getActions($rule_type));
@@ -180,8 +183,4 @@ final class HeraldManiphestTaskAdapter extends HeraldAdapter {
     return $result;
   }
 
-  protected function getCustomFieldTemplateObject() {
-    return new ManiphestTask();
-  }
-
 }

src/applications/herald/adapter/HeraldPholioMockAdapter.php

@@ -13,6 +13,10 @@ final class HeraldPholioMockAdapter extends HeraldAdapter {
     return pht('React to mocks being created or updated.');
   }
 
+  public function newObject() {
+    return new PholioMock();
+  }
+
   public function getObject() {
     return $this->mock;
   }

src/applications/phriction/herald/PhrictionDocumentHeraldAdapter.php

@@ -13,6 +13,10 @@ final class PhrictionDocumentHeraldAdapter extends HeraldAdapter {
     return pht('React to wiki documents being created or updated.');
   }
 
+  public function newObject() {
+    return new PhrictionDocument();
+  }
+
   public function getObject() {
     return $this->document;
   }