gitindex: Add GitIndex.add_files_from_working_tree()

This is like GitIndex.add_files_from_index_info, but uses the working
tree and a list of paths. This is more convenient when the changes exist
in the working tree.

The comment describes its relationship with
GitIndex.add_files_from_index_info, but it is faster, since it calls out
to `git add` rather than calling out to `git hash-object` for every file.

1 files changed, 12 insertions, 0 deletions

diff --git a/morphlib/gitindex_tests.py b/morphlib/gitindex_tests.py
index af0e0444..94444091 100644
--- a/morphlib/gitindex_tests.py
+++ b/morphlib/gitindex_tests.py
@@ -73,3 +73,15 @@ class GitIndexTests(unittest.TestCase):
             idx.add_files_from_index_info(
                 [(os.stat(filepath).st_mode, sha1, 'foo')])
         self.assertEqual(list(idx.get_uncommitted_changes()),[])
+
+    def test_add_files_from_working_tree(self):
+        gd = morphlib.gitdir.GitDirectory(self.dirname)
+        idx = gd.get_index()
+        idx.add_files_from_working_tree(['foo'])
+        self.assertEqual(list(idx.get_uncommitted_changes()),[])
+
+    def test_add_files_from_working_tree_fails_in_bare(self):
+        gd = morphlib.gitdir.GitDirectory(self.mirror)
+        idx = gd.get_index()
+        self.assertRaises(morphlib.gitdir.NoWorkingTreeError,
+                          idx.add_files_from_working_tree, ['foo'])