[StGit PATCH 3/4] Teach new infrastructure to diff two trees

["Karl Hasselström" <kha@treskal.com>]

Nothing uses this yet, but "stg edit" will soon.

Signed-off-by: Karl Hasselström <kha@treskal.com>

---

 stgit/lib/git.py |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)


diff --git a/stgit/lib/git.py b/stgit/lib/git.py
index 9cb2521..d75f724 100644
--- a/stgit/lib/git.py
+++ b/stgit/lib/git.py
@@ -1,5 +1,6 @@
 import os, os.path, re
 from stgit import exception, run, utils
+from stgit.config import config
 
 class RepositoryException(exception.StgException):
     pass
@@ -355,6 +356,11 @@ class Repository(RunWithEnv):
                 return None
         finally:
             index.delete()
+    def diff_tree(self, t1, t2, diff_opts):
+        assert isinstance(t1, Tree)
+        assert isinstance(t2, Tree)
+        return self.run(['git', 'diff-tree', '-p'] + list(diff_opts)
+                        + [t1.sha1, t2.sha1]).raw_output()
 
 class MergeException(exception.StgException):
     pass