From ee6357386d0bfbccd32d6756322743985a9d8fe6 Mon Sep 17 00:00:00 2001
From: Alex Vandiver <alexmv@dropbox.com>
Date: Wed, 10 Aug 2016 14:32:37 -0700
Subject: [PATCH] Correctly parse file renames and copies from `git diff --raw`

Summary:
`parseGitRawDiff` dealt with the `A`, `M`, and `D` status flags from
`git diff --raw`, for file additions, modifications, and deletions
respectively.  However, it failed to cope with `C` and `R` flags, for
copies and renames.  Git version 2.9 and above default to resolving
renames, even in `git diff --raw` output, making this lack of support
only salient now (though users with Git's `diff.rename` set
encountered it previously).

Those two flags differ from the other three in that they offer both the
source and destination filename, separated by a tab.  As
`parseGitRawDiff` was not aware of this property, it returned a
"filename" of `"oldfile\tnewfile"`.  This is surfaced in several
places, including as passed to linters as a filename to check.
Needless to say, this file is nearly guaranteed to never exist on
disk.

Detect both the `C` and `R` flag types, and generate either a file
addition, or a pair of addition/deletion entries.

Test Plan:
Renamed a file, with a linter that printed each file it was
called with.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: jboning, Korvin

Differential Revision: https://secure.phabricator.com/D16387
---
 src/repository/api/ArcanistGitAPI.php | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/src/repository/api/ArcanistGitAPI.php b/src/repository/api/ArcanistGitAPI.php
index 884d65dc..57078dab 100644
--- a/src/repository/api/ArcanistGitAPI.php
+++ b/src/repository/api/ArcanistGitAPI.php
@@ -826,6 +826,22 @@ final class ArcanistGitAPI extends ArcanistRepositoryAPI {
         $mask |= self::FLAG_EXTERNALS;
       } else if (isset($flags[$flag])) {
         $mask |= $flags[$flag];
+      } else if ($flag[0] == 'R') {
+        $both = explode("\t", $file);
+        if ($full) {
+          $files[$both[0]] = array(
+            'mask' => $mask | self::FLAG_DELETED,
+            'ref'  => str_repeat('0', 40),
+          );
+        } else {
+          $files[$both[0]] = $mask | self::FLAG_DELETED;
+        }
+        $file = $both[1];
+        $mask |= self::FLAG_ADDED;
+      } else if ($flag[0] == 'C') {
+        $both = explode("\t", $file);
+        $file = $both[1];
+        $mask |= self::FLAG_ADDED;
       }
 
       if ($full) {