Fix gclient branch ref mangling and allow --force branch switches.

tests/scm_unittest.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Unit tests for scm.py."""
 
 import logging
 import os
 import sys
@@ skipping 80 matching lines @@
         'GetPatchName',
         'GetSha1ForSvnRev',
         'GetSVNBranch',
         'GetUpstreamBranch',
         'IsGitSvn',
         'IsInsideWorkTree',
         'IsValidRevision',
         'IsWorkTreeDirty',
         'MatchSvnGlob',
         'ParseGitSvnSha1',
+        'RefToRemoteRef',
         'ShortBranchName',
     ]
     # If this test fails, you should add the relevant test.
     self.compareMembers(scm.GIT, members)
 
   def testGetEmail(self):
     self.mox.StubOutWithMock(scm.GIT, 'Capture')
     scm.GIT.Capture(['config', 'user.email'], cwd=self.root_dir
                     ).AndReturn('mini@me.com')
     self.mox.ReplayAll()
     self.assertEqual(scm.GIT.GetEmail(self.root_dir), 'mini@me.com')
 
   def testMatchSvnGlob(self):
     self.assertEquals(scm.GIT.MatchSvnGlob(
         'svn://svn.chromium.org/chrome/trunk/src',
         'svn://svn.chromium.org/chrome',
         'trunk/src:refs/remotes/origin/trunk',
         False), 'refs/remotes/origin/trunk')
     self.assertEquals(scm.GIT.MatchSvnGlob(
         'https://v8.googlecode.com/svn/branches/bleeding_edge',
         'https://v8.googlecode.com/svn',
         'branches/*:refs/remotes/*',
         True), 'refs/remotes/bleeding_edge')
 
+  def testRefToRemoteRefNoRemote(self):
+    refs = {
+        # local ref for upstream branch-head
+        'refs/remotes/branch-heads/1234': ('refs/remotes/branch-heads/',
+                                           '1234'),
+        # upstream ref for branch-head
+        'refs/branch-heads/1234': ('refs/remotes/branch-heads/', '1234'),
+        # could be either local or upstream ref, assumed to refer to
+        # upstream, but probably don't want to encourage refs like this.
+        'branch-heads/1234': ('refs/remotes/branch-heads/', '1234'),
+        # actively discouraging refs like this, should prepend with 'refs/'
+        'remotes/branch-heads/1234': None,
+        # might be non-"branch-heads" upstream branches, but can't resolve
+        # without knowing the remote.
+        'refs/heads/1234': None,
+        'heads/1234': None,
+        # underspecified, probably intended to refer to a local branch
+        '1234': None,
+        }
+    for k, v in refs.items():
+      r = scm.GIT.RefToRemoteRef(k)
+      self.assertEqual(r, v, msg='%s -> %s, expected %s' % (k, r, v))
+
+  def testRefToRemoteRefWithRemote(self):
+    remote = 'origin'
+    refs = {
+        # This shouldn't be any different from the NoRemote() version.
+        'refs/branch-heads/1234': ('refs/remotes/branch-heads/', '1234'),
+        # local refs for upstream branch
+        'refs/remotes/%s/foobar' % remote: ('refs/remotes/%s/' % remote,
+                                            'foobar'),
+        '%s/foobar' % remote: ('refs/remotes/%s/' % remote, 'foobar'),
+        # upstream ref for branch
+        'refs/heads/foobar': ('refs/remotes/%s/' % remote, 'foobar'),
+        # could be either local or upstream ref, assumed to refer to
+        # upstream, but probably don't want to encourage refs like this.
+        'heads/foobar': ('refs/remotes/%s/' % remote, 'foobar'),
+        # underspecified, probably intended to refer to a local branch
+        'foobar': None,
+        }
+    for k, v in refs.items():
+      r = scm.GIT.RefToRemoteRef(k, remote)
+      self.assertEqual(r, v, msg='%s -> %s, expected %s' % (k, r, v))
+
 
 class RealGitTest(fake_repos.FakeReposTestBase):
   def setUp(self):
     super(RealGitTest, self).setUp()
     self.enabled = self.FAKE_REPOS.set_up_git()
     if self.enabled:
       self.clone_dir = scm.os.path.join(self.FAKE_REPOS.git_root, 'repo_1')
 
   def testIsValidRevision(self):
     if not self.enabled:
@@ skipping 347 matching lines @@
     # Asserting the tree is not sufficient, svn status must come out clear too.
     self.assertEquals('', self._capture(['status']))
 
 
 if __name__ == '__main__':
   if '-v' in sys.argv:
     logging.basicConfig(level=logging.DEBUG)
   unittest.main()
 
 # vim: ts=2:sw=2:tw=80:et: