From 5ca985edb3d429967cd40d34229db19a1b7c6b0a Mon Sep 17 00:00:00 2001
From: Michael Drake <michael.drake@codethink.co.uk>
Date: Wed, 18 Mar 2015 18:13:51 +0000
Subject: Add functions for checking which tags/branches contain a ref

Change-Id: Ic6e613c21ed26c528ad7c75f41af01d7552729fd
---
 morphlib/gitdir.py       | 26 ++++++++++++++++++++++++++
 morphlib/gitdir_tests.py | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/morphlib/gitdir.py b/morphlib/gitdir.py
index 03640a22..1c286720 100644
--- a/morphlib/gitdir.py
+++ b/morphlib/gitdir.py
@@ -681,6 +681,32 @@ class GitDirectory(object):
         if not morphlib.git.is_valid_sha1(string):
             raise ExpectedSha1Error(string)
 
+    def _check_ref_exists(self, ref):
+        self._rev_parse('%s^{commit}' % ref)
+
+    def _gitcmd_output_list(self, *args):
+        output = morphlib.git.gitcmd(self._runcmd, *args)
+        separated = [l.strip() for l in output.splitlines()]
+        prefix = '* '
+        for i, l in enumerate(separated):
+            if l.startswith(prefix):
+                separated[i] = l[len(prefix):]
+        return separated
+
+    def tags_containing_sha1(self, ref): # pragma: no cover
+        self._check_is_sha1(ref)
+        self._check_ref_exists(ref)
+
+        args = ['tag', '--contains', ref]
+        return self._gitcmd_output_list(*args)
+
+    def branches_containing_sha1(self, ref):
+        self._check_is_sha1(ref)
+        self._check_ref_exists(ref)
+
+        args = ['branch', '--contains', ref]
+        return self._gitcmd_output_list(*args)
+
     def _update_ref(self, ref_args, message):
         args = ['update-ref']
         # No test coverage, since while this functionality is useful,
diff --git a/morphlib/gitdir_tests.py b/morphlib/gitdir_tests.py
index a6e1921d..f606dfe7 100644
--- a/morphlib/gitdir_tests.py
+++ b/morphlib/gitdir_tests.py
@@ -95,6 +95,38 @@ class GitDirectoryTests(unittest.TestCase):
         self.assertIsInstance(gitdir.get_index(), morphlib.gitindex.GitIndex)
 
 
+class GitDirectoryAnchoredRefTests(unittest.TestCase):
+
+    def setUp(self):
+        self.tempdir = tempfile.mkdtemp()
+        self.dirname = os.path.join(self.tempdir, 'foo')
+        os.mkdir(self.dirname)
+        gd = morphlib.gitdir.init(self.dirname)
+        with open(os.path.join(self.dirname, 'test_file.morph'), "w") as f:
+            f.write('dummy morphology text')
+        morphlib.git.gitcmd(gd._runcmd, 'add', '.')
+        morphlib.git.gitcmd(gd._runcmd, 'commit', '-m', 'Initial commit')
+
+    def tearDown(self):
+        shutil.rmtree(self.tempdir)
+
+    def test_ref_anchored_in_branch(self):
+        gd = morphlib.gitdir.GitDirectory(self.dirname)
+        output = morphlib.git.gitcmd(gd._runcmd, 'rev-parse', 'HEAD')
+        ref = output.strip()
+
+        self.assertEqual(len(gd.branches_containing_sha1(ref)), 1)
+        self.assertEqual(gd.branches_containing_sha1(ref)[0], 'master')
+
+    def test_ref_not_anchored_in_branch(self):
+        gd = morphlib.gitdir.GitDirectory(self.dirname)
+        output = morphlib.git.gitcmd(gd._runcmd, 'rev-parse', 'HEAD')
+        ref = output.strip()
+
+        morphlib.git.gitcmd(gd._runcmd, 'commit', '--amend', '-m',
+                            'New commit message')
+        self.assertEqual(len(gd.branches_containing_sha1(ref)), 0)
+
 class GitDirectoryContentsTests(unittest.TestCase):
 
     def setUp(self):
-- 
cgit v1.2.1