From 87f8dbefda89bf6cb9e4b88f23a5317b054da0d4 Mon Sep 17 00:00:00 2001
From: Michael Drake <michael.drake@codethink.co.uk>
Date: Mon, 13 Apr 2015 14:17:29 +0000
Subject: Add version guessing function to gitdir and cached repo.

Change-Id: I1c79ce68a7a7534d36a9e83210e18a58e7b648e8
---
 morphlib/cachedrepo.py | 9 +++++++++
 morphlib/gitdir.py     | 6 ++++++
 2 files changed, 15 insertions(+)

diff --git a/morphlib/cachedrepo.py b/morphlib/cachedrepo.py
index 0c0f5cb7..a630cc29 100644
--- a/morphlib/cachedrepo.py
+++ b/morphlib/cachedrepo.py
@@ -143,6 +143,15 @@ class CachedRepo(object):
         '''
         return self._gitdir.branches_containing_sha1(ref)
 
+    def version_guess(self, ref): # pragma: no cover
+        '''Guess version number using `git describe --tags`
+
+        Raises a gitdir.InvalidRefError if the ref is not found in the
+        repository.
+
+        '''
+        return self._gitdir.version_guess(ref)
+
     def list_files(self, ref, recurse=True):  # pragma: no cover
         '''Return filenames found in the tree pointed to by the given ref.
 
diff --git a/morphlib/gitdir.py b/morphlib/gitdir.py
index 1c286720..a6dd26a1 100644
--- a/morphlib/gitdir.py
+++ b/morphlib/gitdir.py
@@ -707,6 +707,12 @@ class GitDirectory(object):
         args = ['branch', '--contains', ref]
         return self._gitcmd_output_list(*args)
 
+    def version_guess(self, ref): # pragma: no cover
+        self._check_ref_exists(ref)
+
+        args = ['describe', '--tags', '--always', ref]
+        return morphlib.git.gitcmd(self._runcmd, *args).strip()
+
     def _update_ref(self, ref_args, message):
         args = ['update-ref']
         # No test coverage, since while this functionality is useful,
-- 
cgit v1.2.1