From 81b2b84112a36f93c5032434b094469f1f22cf2b Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Wed, 19 Jun 2013 11:44:16 +0200
Subject: [PATCH] Clean up git env vars consistently

---
 src/Composer/Downloader/GitDownloader.php |  2 ++
 src/Composer/Util/Git.php                 | 12 +++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/Composer/Downloader/GitDownloader.php b/src/Composer/Downloader/GitDownloader.php
index 55c80dba6..f59c6a68b 100644
--- a/src/Composer/Downloader/GitDownloader.php
+++ b/src/Composer/Downloader/GitDownloader.php
@@ -77,6 +77,7 @@ class GitDownloader extends VcsDownloader
      */
     public function getLocalChanges($path)
     {
+        $this->cleanEnv();
         $path = $this->normalizePath($path);
         if (!is_dir($path.'/.git')) {
             return;
@@ -95,6 +96,7 @@ class GitDownloader extends VcsDownloader
      */
     protected function cleanChanges($path, $update)
     {
+        $this->cleanEnv();
         $path = $this->normalizePath($path);
         if (!$changes = $this->getLocalChanges($path)) {
             return;
diff --git a/src/Composer/Util/Git.php b/src/Composer/Util/Git.php
index 3200688a9..6abb9c7c6 100644
--- a/src/Composer/Util/Git.php
+++ b/src/Composer/Util/Git.php
@@ -26,10 +26,16 @@ class Git
         }
 
         // added in git 1.7.1, prevents prompting the user for username/password
-        putenv('GIT_ASKPASS=echo');
+        if (getenv('GIT_ASKPASS') !== 'echo') {
+            putenv('GIT_ASKPASS=echo');
+        }
 
         // clean up rogue git env vars in case this is running in a git hook
-        putenv('GIT_DIR');
-        putenv('GIT_WORK_TREE');
+        if (getenv('GIT_DIR')) {
+            putenv('GIT_DIR');
+        }
+        if (getenv('GIT_WORK_TREE')) {
+            putenv('GIT_WORK_TREE');
+        }
     }
 }