Guess upstream-tag based on merge-base

In some unfortunate cases you might have something like this:

$ git tag
v1.0
vyatta/1.0-0something1

... where later tag is closer to describe current HEAD.

With upstream-tag set to v%(version)s find_tag() is going to propose
something based on vyatta/1.0-0something1 which is not expected.

The problem is that find_tag() returns tags, which match the
upstream-tag format, but which are not on the upstream-branch at all.

To fix this find_tag()/git-describe should not be used to determine
the closest upstream-tag.

Closes: gh#7

1 files changed, 15 insertions, 0 deletions

diff --git a/gbp/git/repository.py b/gbp/git/repository.py
index 689430f0..3b208bf4 100644
--- a/gbp/git/repository.py
+++ b/gbp/git/repository.py
@@ -713,6 +713,21 @@ class GitRepository(object):
         """
         return self.describe(commit, pattern, abbrev=0)
 
+    def find_branch_tag(self, commit, branch, pattern=None):
+        """
+        Find the closest tag on a certain branch to a given commit
+
+        @param commit: the commit to describe
+        @type commit: C{str}
+        @type branch: C{str}
+        @param pattern: only look for tags matching I{pattern}
+        @type pattern: C{str}
+        @return: the found tag
+        @rtype: C{str}
+        """
+        base_commit = self.get_merge_base(commit, branch)
+        return self.describe(base_commit, pattern, abbrev=0)
+
     def get_tags(self, pattern=None):
         """
         List tags