Add a relation table for Revisions to local commit hashes

Summary:
This allows us to performantly query for diffs related to a given local hash.
Immediate applications are:

  - Commit detection in Mercurial and Git-Immutable workflows.
  - Some async unit test stuff @mgummelt was doing.

Test Plan:
Diffed locally under SVN/Git/hg, checked the table, got sensible output.

  mysql> select * from differential_revisionhash;
  +------------+------+------------------------------------------+
  | revisionID | type | hash                                     |
  +------------+------+------------------------------------------+
  |         40 | gtcm | 8c6fb2f95598a50f7aac64a5f4cc6c12b5db42f5 |
  |         40 | gttr | 54710e361a465f4ff39565a93b2a221b6e7dd07c |
  |         41 | hgcm | c29cb69aec14                             |
  |         41 | hgcm | e7309be4eabb                             |
  |         41 | hgcm | 4e885caeff60                             |
  |         41 | hgcm | 213ee1cd30ea                             |
  |         41 | hgcm | b4050fb3490f                             |
  |         41 | hgcm | 72a76bd7ffa2                             |
  |         41 | hgcm | 06c2687e63fb                             |
  |         41 | hgcm | 2b464bde6b48                             |
  +------------+------+------------------------------------------+
  10 rows in set (0.00 sec)

NOTE: Mercurial hashes are short-form but I'll shoot out a separate Arcanist
diff to fix this.

Reviewers: Makinde, fratrik, mgummelt, jungejason, nh, tuomaspelkonen, aran

Reviewed By: Makinde

CC: aran, Makinde

Differential Revision: 961

resources/sql/patches/075.revisionhash.sql

@@ -0,0 +1,7 @@
+CREATE TABLE phabricator_differential.differential_revisionhash (
+  revisionID INT UNSIGNED NOT NULL,
+  type CHAR(4) BINARY NOT NULL,
+  hash VARCHAR(40) BINARY NOT NULL,
+  KEY (type, hash),
+  KEY (revisionID)
+) ENGINE=InnoDB;

src/__phutil_library_map__.php

@@ -215,6 +215,7 @@ phutil_register_library_map(array(
     'DifferentialRevisionDetailView' => 'applications/differential/view/revisiondetail',
     'DifferentialRevisionEditController' => 'applications/differential/controller/revisionedit',
     'DifferentialRevisionEditor' => 'applications/differential/editor/revision',
+    'DifferentialRevisionHash' => 'applications/differential/constants/revisionhash',
     'DifferentialRevisionIDFieldSpecification' => 'applications/differential/field/specification/revisionid',
     'DifferentialRevisionListController' => 'applications/differential/controller/revisionlist',
     'DifferentialRevisionListData' => 'applications/differential/data/revisionlist',

src/applications/differential/constants/revisioncontrolsystem/DifferentialRevisionControlSystem.php

@@ -16,9 +16,11 @@
  * limitations under the License.
  */
 
+// TODO: Unify with similar Repository constants
 final class DifferentialRevisionControlSystem {
 
-  const SVN = 'svn';
+  const SVN         = 'svn';
-  const GIT = 'git';
+  const GIT         = 'git';
+  const MERCURIAL   = 'hg';
 
 }

src/applications/differential/constants/revisionhash/DifferentialRevisionHash.php

@@ -0,0 +1,27 @@
+<?php
+
+/*
+ * Copyright 2011 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+final class DifferentialRevisionHash {
+
+  const TABLE_NAME = 'differential_revisionhash';
+
+  const HASH_GIT_COMMIT         = 'gtcm';
+  const HASH_GIT_TREE           = 'gttr';
+  const HASH_MERCURIAL_COMMIT   = 'hgcm';
+
+}

src/applications/differential/constants/revisionhash/__init__.php

@@ -0,0 +1,10 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+
+phutil_require_source('DifferentialRevisionHash.php');

src/applications/differential/editor/revision/DifferentialRevisionEditor.php

@@ -365,6 +365,7 @@ class DifferentialRevisionEditor {
       $diff->save();
 
       $this->updateAffectedPathTable($revision, $diff, $changesets);
+      $this->updateRevisionHashTable($revision, $diff);
 
       // An updated diff should require review, as long as it's not committed
       // or accepted. The "accepted" status is "sticky" to encourage courtesy
@@ -722,7 +723,7 @@ class DifferentialRevisionEditor {
   }
 
   /**
-   * Updated the table which links Differential revisions to paths they affect,
+   * Update the table which links Differential revisions to paths they affect,
    * so Diffusion can efficiently find pending revisions for a given file.
    */
   private function updateAffectedPathTable(
@@ -810,5 +811,83 @@ class DifferentialRevisionEditor {
     }
   }
 
+
+  /**
+   * Update the table connecting revisions to DVCS local hashes, so we can
+   * identify revisions by commit/tree hashes.
+   */
+  private function updateRevisionHashTable(
+    DifferentialRevision $revision,
+    DifferentialDiff $diff) {
+
+    $vcs = $diff->getSourceControlSystem();
+    if ($vcs == DifferentialRevisionControlSystem::SVN) {
+      // Subversion has no local commit or tree hash information, so we don't
+      // have to do anything.
+      return;
+    }
+
+    $property = id(new DifferentialDiffProperty())->loadOneWhere(
+      'diffID = %d AND name = %s',
+      $diff->getID(),
+      'local:commits');
+    if (!$property) {
+      return;
+    }
+
+    $hashes = array();
+
+    $data = $property->getData();
+    switch ($vcs) {
+      case DifferentialRevisionControlSystem::GIT:
+        foreach ($data as $commit) {
+          $hashes[] = array(
+            DifferentialRevisionHash::HASH_GIT_COMMIT,
+            $commit['commit'],
+          );
+          $hashes[] = array(
+            DifferentialRevisionHash::HASH_GIT_TREE,
+            $commit['tree'],
+          );
+        }
+        break;
+      case DifferentialRevisionControlSystem::MERCURIAL:
+        foreach ($data as $commit) {
+          $hashes[] = array(
+            DifferentialRevisionHash::HASH_MERCURIAL_COMMIT,
+            $commit['rev'],
+          );
+        }
+        break;
+    }
+
+    $conn_w = $revision->establishConnection('w');
+
+    $sql = array();
+    foreach ($hashes as $info) {
+      list($type, $hash) = $info;
+      $sql[] = qsprintf(
+        $conn_w,
+        '(%d, %s, %s)',
+        $revision->getID(),
+        $type,
+        $hash);
+    }
+
+    queryfx(
+      $conn_w,
+      'DELETE FROM %T WHERE revisionID = %d',
+      DifferentialRevisionHash::TABLE_NAME,
+      $revision->getID());
+
+    if ($sql) {
+      queryfx(
+        $conn_w,
+        'INSERT INTO %T (revisionID, type, hash) VALUES %Q',
+        DifferentialRevisionHash::TABLE_NAME,
+        implode(', ', $sql));
+    }
+  }
+
 }
 

src/applications/differential/editor/revision/__init__.php

@@ -7,6 +7,8 @@
 
 
 phutil_require_module('phabricator', 'applications/differential/constants/action');
+phutil_require_module('phabricator', 'applications/differential/constants/revisioncontrolsystem');
+phutil_require_module('phabricator', 'applications/differential/constants/revisionhash');
 phutil_require_module('phabricator', 'applications/differential/constants/revisionstatus');
 phutil_require_module('phabricator', 'applications/differential/field/selector/base');
 phutil_require_module('phabricator', 'applications/differential/mail/ccwelcome');
@@ -14,6 +16,7 @@ phutil_require_module('phabricator', 'applications/differential/mail/newdiff');
 phutil_require_module('phabricator', 'applications/differential/storage/affectedpath');
 phutil_require_module('phabricator', 'applications/differential/storage/auxiliaryfield');
 phutil_require_module('phabricator', 'applications/differential/storage/comment');
+phutil_require_module('phabricator', 'applications/differential/storage/diffproperty');
 phutil_require_module('phabricator', 'applications/differential/storage/revision');
 phutil_require_module('phabricator', 'applications/diffusion/query/pathid/base');
 phutil_require_module('phabricator', 'applications/feed/constants/story');