Begin adding "pro" modular transaction fields to Differential

Summary:
Ref T11114. Currently, all of Differential is extremely custom CustomFields. I want to back away from that somewhat and leverage more EditEngine / ModularTransactions infrastructure.

This allows EditEngine, ModularTransactions, and CustomFields to coexist in an uneasy peace. The "EditPro" controller applies a //different edit// than the CustomFields do, but everything works out in the end. I think.

Hopefully the horrible mess I am creating here will be short-lived.

Test Plan:
  - Edited a revision with the normal editor.
  - Edited a revision with the pro editor.
  - Created a revision with `arc diff`.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11114

Differential Revision: https://secure.phabricator.com/D17044

src/__phutil_library_map__.php

@@ -553,6 +553,8 @@ phutil_register_library_map(array(
     'DifferentialRevisionStatus' => 'applications/differential/constants/DifferentialRevisionStatus.php',
     'DifferentialRevisionSummaryHeraldField' => 'applications/differential/herald/DifferentialRevisionSummaryHeraldField.php',
     'DifferentialRevisionTitleHeraldField' => 'applications/differential/herald/DifferentialRevisionTitleHeraldField.php',
+    'DifferentialRevisionTitleTransaction' => 'applications/differential/xaction/DifferentialRevisionTitleTransaction.php',
+    'DifferentialRevisionTransactionType' => 'applications/differential/xaction/DifferentialRevisionTransactionType.php',
     'DifferentialRevisionUpdateHistoryView' => 'applications/differential/view/DifferentialRevisionUpdateHistoryView.php',
     'DifferentialRevisionViewController' => 'applications/differential/controller/DifferentialRevisionViewController.php',
     'DifferentialSchemaSpec' => 'applications/differential/storage/DifferentialSchemaSpec.php',
@@ -5201,6 +5203,8 @@ phutil_register_library_map(array(
     'DifferentialRevisionStatus' => 'Phobject',
     'DifferentialRevisionSummaryHeraldField' => 'DifferentialRevisionHeraldField',
     'DifferentialRevisionTitleHeraldField' => 'DifferentialRevisionHeraldField',
+    'DifferentialRevisionTitleTransaction' => 'DifferentialRevisionTransactionType',
+    'DifferentialRevisionTransactionType' => 'PhabricatorModularTransactionType',
     'DifferentialRevisionUpdateHistoryView' => 'AphrontView',
     'DifferentialRevisionViewController' => 'DifferentialController',
     'DifferentialSchemaSpec' => 'PhabricatorConfigSchemaSpec',
@@ -5210,7 +5214,7 @@ phutil_register_library_map(array(
     'DifferentialSummaryField' => 'DifferentialCoreCustomField',
     'DifferentialTestPlanField' => 'DifferentialCoreCustomField',
     'DifferentialTitleField' => 'DifferentialCoreCustomField',
-    'DifferentialTransaction' => 'PhabricatorApplicationTransaction',
+    'DifferentialTransaction' => 'PhabricatorModularTransaction',
     'DifferentialTransactionComment' => 'PhabricatorApplicationTransactionComment',
     'DifferentialTransactionEditor' => 'PhabricatorApplicationTransactionEditor',
     'DifferentialTransactionQuery' => 'PhabricatorApplicationTransactionQuery',

src/applications/differential/editor/DifferentialRevisionEditEngine.php

@@ -60,7 +60,17 @@ final class DifferentialRevisionEditEngine
   }
 
   protected function buildCustomEditFields($object) {
-    return array();
+    return array(
+      id(new PhabricatorTextEditField())
+        ->setKey('title')
+        ->setLabel(pht('Title'))
+        ->setTransactionType(
+          DifferentialRevisionTitleTransaction::TRANSACTIONTYPE)
+        ->setDescription(pht('The title of the revision.'))
+        ->setConduitDescription(pht('Retitle the revision.'))
+        ->setConduitTypeDescription(pht('New revision title.'))
+        ->setValue($object->getTitle()),
+    );
   }
 
 }

src/applications/differential/storage/DifferentialTransaction.php

@@ -1,6 +1,7 @@
 <?php
 
-final class DifferentialTransaction extends PhabricatorApplicationTransaction {
+final class DifferentialTransaction
+  extends PhabricatorModularTransaction {
 
   private $isCommandeerSideEffect;
 
@@ -17,6 +18,9 @@ final class DifferentialTransaction extends PhabricatorApplicationTransaction {
   const MAILTAG_REVIEW_REQUEST = 'differential-review-request';
   const MAILTAG_OTHER          = 'differential-other';
 
+  public function getBaseTransactionClass() {
+    return 'DifferentialRevisionTransactionType';
+  }
 
   public function setIsCommandeerSideEffect($is_side_effect) {
     $this->isCommandeerSideEffect = $is_side_effect;

src/applications/differential/xaction/DifferentialRevisionTitleTransaction.php

@@ -0,0 +1,57 @@
+<?php
+
+final class DifferentialRevisionTitleTransaction
+  extends DifferentialRevisionTransactionType {
+
+  const TRANSACTIONTYPE = 'differential.revision.title';
+
+  public function generateOldValue($object) {
+    return $object->getTitle();
+  }
+
+  public function applyInternalEffects($object, $value) {
+    $object->setTitle($value);
+  }
+
+  public function getTitle() {
+    return pht(
+      '%s retitled this revision from %s to %s.',
+      $this->renderAuthor(),
+      $this->renderOldValue(),
+      $this->renderNewValue());
+  }
+
+  public function getTitleForFeed() {
+    return pht(
+      '%s retitled %s from %s to %s.',
+      $this->renderAuthor(),
+      $this->renderObject(),
+      $this->renderOldValue(),
+      $this->renderNewValue());
+  }
+
+  public function validateTransactions($object, array $xactions) {
+    $errors = array();
+
+    if ($this->isEmptyTextTransaction($object->getTitle(), $xactions)) {
+      $errors[] = $this->newRequiredError(
+        pht('Revisions must have a title.'));
+    }
+
+    $max_length = $object->getColumnMaximumByteLength('title');
+    foreach ($xactions as $xaction) {
+      $new_value = $xaction->getNewValue();
+      $new_length = strlen($new_value);
+      if ($new_length > $max_length) {
+        $errors[] = $this->newInvalidError(
+          pht(
+            'Revision title is too long: the maximum length of a '.
+            'revision title is 255 bytes.'),
+          $xaction);
+      }
+    }
+
+    return $errors;
+  }
+
+}

src/applications/differential/xaction/DifferentialRevisionTransactionType.php

@@ -0,0 +1,4 @@
+<?php
+
+abstract class DifferentialRevisionTransactionType
+  extends PhabricatorModularTransactionType {}

src/applications/transactions/storage/PhabricatorModularTransaction.php

@@ -1,5 +1,9 @@
 <?php
 
+// TODO: Some "final" modifiers have been VERY TEMPORARILY moved aside to
+// allow DifferentialTransaction to extend this class without converting
+// fully to ModularTransactions.
+
 abstract class PhabricatorModularTransaction
   extends PhabricatorApplicationTransaction {
 
@@ -76,7 +80,7 @@ abstract class PhabricatorModularTransaction
       ->applyExternalEffects($object);
   }
 
-  final public function shouldHide() {
+  /* final */ public function shouldHide() {
     if ($this->getTransactionImplementation()->shouldHide()) {
       return true;
     }
@@ -84,7 +88,7 @@ abstract class PhabricatorModularTransaction
     return parent::shouldHide();
   }
 
-  final public function getIcon() {
+  /* final */ public function getIcon() {
     $icon = $this->getTransactionImplementation()->getIcon();
     if ($icon !== null) {
       return $icon;
@@ -93,7 +97,7 @@ abstract class PhabricatorModularTransaction
     return parent::getIcon();
   }
 
-  final public function getTitle() {
+  /* final */ public function getTitle() {
     $title = $this->getTransactionImplementation()->getTitle();
     if ($title !== null) {
       return $title;
@@ -111,7 +115,7 @@ abstract class PhabricatorModularTransaction
     return $title;
   }
 
-  final public function getTitleForFeed() {
+  /* final */ public function getTitleForFeed() {
     $title = $this->getTransactionImplementation()->getTitleForFeed();
     if ($title !== null) {
       return $title;
@@ -120,7 +124,7 @@ abstract class PhabricatorModularTransaction
     return parent::getTitleForFeed();
   }
 
-  final public function getColor() {
+  /* final */ public function getColor() {
     $color = $this->getTransactionImplementation()->getColor();
     if ($color !== null) {
       return $color;