[jhbuild] git: Add support for checking out an arbitrary commit

[Colin Walters <walters src gnome org>]

commit 78d52b55d4be487d8d6014b16012b8c754a306f5
Author: Colin Walters <walters verbum org>
Date:   Wed Nov 9 12:05:58 2011 -0500

    git: Add support for checking out an arbitrary commit
    
    I want to back out cogl to a specific commit before a broken one.

 jhbuild/versioncontrol/git.py |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/jhbuild/versioncontrol/git.py b/jhbuild/versioncontrol/git.py
index 80c6070..11c01e4 100644
--- a/jhbuild/versioncontrol/git.py
+++ b/jhbuild/versioncontrol/git.py
@@ -175,8 +175,11 @@ class GitBranch(Branch):
         return True
 
     def is_local_branch(self, branch):
-        return self.execute_git_predicate( ['git', 'show-ref', '--quiet',
-                '--verify', 'refs/heads/' + branch])
+        is_local_head = self.execute_git_predicate( ['git', 'show-ref', '--quiet',
+                                                     '--verify', 'refs/heads/' + branch])
+        if is_local_head:
+            return True
+        return self.execute_git_predicate(['git', 'rev-parse', branch])
 
     def is_inside_work_tree(self):
         return self.execute_git_predicate(