From 9092994e45c22be487798cbf8dba95e43a3c730b Mon Sep 17 00:00:00 2001
From: vrana <jakubv@fb.com>
Date: Mon, 30 Jul 2012 17:39:30 -0700
Subject: [PATCH] Make old and new files when checking for changes by commit

Summary:
We have some false positives on commit changes checker.
I'm not sure if the reason is a difference between `git diff` and `svn diff` or something else but making this more robust doesn't harm anything.

We couldn't make the files from the whole changeset because I want to ignore context bigger than `$num_lines` to reduce rebase noise.

Test Plan:
Ran the method on diff which had false positive previously.
Ran the method on a diff with real change.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3107
---
 ...torRepositoryCommitMessageParserWorker.php | 24 ++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/applications/repository/worker/commitmessageparser/PhabricatorRepositoryCommitMessageParserWorker.php b/src/applications/repository/worker/commitmessageparser/PhabricatorRepositoryCommitMessageParserWorker.php
index da89a7a698..27eb70a93c 100644
--- a/src/applications/repository/worker/commitmessageparser/PhabricatorRepositoryCommitMessageParserWorker.php
+++ b/src/applications/repository/worker/commitmessageparser/PhabricatorRepositoryCommitMessageParserWorker.php
@@ -292,9 +292,27 @@ abstract class PhabricatorRepositoryCommitMessageParserWorker
         if ($files[$file_phid]->loadFileData() != $corpus) {
           return $vs_diff;
         }
-      } else if ($changeset->makeChangesWithContext() !=
-          $vs_changeset->makeChangesWithContext()) {
-        return $vs_diff;
+      } else {
+        $context = implode("\n", $changeset->makeChangesWithContext());
+        $vs_context = implode("\n", $vs_changeset->makeChangesWithContext());
+
+        // We couldn't just compare $context and $vs_context because following
+        // diffs will be considered different:
+        //
+        //   -(empty line)
+        //   -echo 'test';
+        //    (empty line)
+        //
+        //    (empty line)
+        //   -echo "test";
+        //   -(empty line)
+
+        $hunk = id(new DifferentialHunk())->setChanges($context);
+        $vs_hunk = id(new DifferentialHunk())->setChanges($vs_context);
+        if ($hunk->makeOldFile() != $vs_hunk->makeOldFile() ||
+            $hunk->makeNewFile() != $vs_hunk->makeNewFile()) {
+          return $vs_diff;
+        }
       }
     }