Merge lp:~nskaggs/juju-ci-tools/add-version-branch-support into lp:juju-ci-tools

[Nicholas Skaggs]

Add support for versioned branch from an unversioned repo. This is to support the names + names.v2 repository and similar stories.

http://gopkg.in/juju/names.v2 lives at https://github.com/juju/names/tree/v2, which otherwise clones into 'names', rather than 'names.v2'.

[lp:~nskaggs/juju-ci-tools/add-version-branch-support]

1427. By Nicholas Skaggs on 2016-05-25

use \Z instead of checking length

[Curtis Hovey (sinzui)]

Thank you.

review: Approve (code)

=== modified file 'git_gate.py'
--- git_gate.py	2015-12-14 16:23:40 +0000
+++ git_gate.py	2016-05-25 15:18:07 +0000
@@ -5,6 +5,7 @@
 
 import argparse
 import os
+import re
 import subprocess
 import sys
 
@@ -51,6 +52,8 @@
     git = SubcommandRunner("git")
 
     final_project = args.project
+    if args.project_ref:
+        final_project = version_dir_from_branch(args.project, args.project_ref)
     if args.feature_branch:
         final_project = from_feature_dir(args.project)
 
@@ -91,6 +94,23 @@
     go("test", project_ellipsis)
 
 
+def version_dir_from_branch(directory, branch_name):
+    """
+    For branches of repos that are versioned with gopkg.in,  we need to
+    do some special handling, since the test code expects the version to be
+    appended to the reponame with a ".".  However, the version is different
+    than the base gopkg.in branch.  To account for this, we use the convention
+    that a version branch is named v[0-9], and clone accordingly.
+
+    Thus, the branch for gopkg.in/juju/charm.v6 would be from a git repo
+    named charm, tagged v6, which should end up in
+    $GOPATH/src/gokpg.in/juju/charm.v6
+    """
+    if re.match('[v]\d\Z', branch_name):
+        return directory + '.' + branch_name
+    return directory
+
+
 def from_feature_dir(directory):
     """
     For feature branches on repos that are versioned with gopkg.in,  we need to