Allow using fast_import for more than initial commit.

gitosis/repository.py

@@ -63,6 +63,7 @@ def fast_import(
     commit_msg,
     committer,
     files,
+    parent=None,
     ):
     """
     Create an initial commit.
@@ -97,10 +98,17 @@ committer %(committer)s now
 data %(commit_msg_len)d
 %(commit_msg)s
 """ % dict(
-        committer=committer,
-        commit_msg_len=len(commit_msg),
-        commit_msg=commit_msg,
-        ))
+            committer=committer,
+            commit_msg_len=len(commit_msg),
+            commit_msg=commit_msg,
+            ))
+    if parent is not None:
+        assert not parent.startswith(':')
+        child.stdin.write("""\
+from %(parent)s
+""" % dict(
+                parent=parent,
+                ))
     for index, (path, content) in enumerate(files):
         child.stdin.write('M 100644 :%d %s\n' % (index+1, path))
     child.stdin.close()

gitosis/test/test_repository.py

@@ -313,3 +313,31 @@ exec git "$@"
     got = readFile(os.path.join(tmp, 'cookie'))
     eq(got, magic_cookie)
 
+def test_fast_import_parent():
+    tmp = maketemp()
+    path = os.path.join(tmp, 'repo.git')
+    repository.init(path=path)
+    repository.fast_import(
+        git_dir=path,
+        commit_msg='foo initial bar',
+        committer='Mr. Unit Test <unit.test@example.com>',
+        files=[
+            ('foo', 'bar\n'),
+            ],
+        )
+    repository.fast_import(
+        git_dir=path,
+        commit_msg='another',
+        committer='Sam One Else <sam@example.com>',
+        parent='refs/heads/master^0',
+        files=[
+            ('quux', 'thud\n'),
+            ],
+        )
+    export = os.path.join(tmp, 'export')
+    repository.export(
+        git_dir=path,
+        path=export,
+        )
+    eq(sorted(os.listdir(export)),
+       sorted(['foo', 'quux']))