gclient: Add better error reporting when path is not a git repo.

tests/gclient_scm_test.py

 #!/usr/bin/python
 #
 # Copyright 2008-2009 Google Inc.  All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #      http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
 """Unit tests for gclient_scm.py."""
 
+import os
 import shutil
 # Import it before super_mox to keep a valid reference.
 from subprocess import Popen, PIPE, STDOUT
 import tempfile
 
 import gclient_scm
 from gclient_test import BaseTestCase as GCBaseTestCase
 from super_mox import mox, SuperMoxBaseTestBase
 
 
@@ skipping 505 matching lines @@
         'See man git-rebase for details.\n'
     self.assertRaisesError(exception, scm.update, options, (), [])
     exception = \
         '\n____ .\n' \
         '\tAlready in a conflict, i.e. (no branch).\n' \
         '\tFix the conflict and run gclient again.\n' \
         '\tOr to abort run:\n\t\tgit-rebase --abort\n' \
         '\tSee man git-rebase for details.\n'
     self.assertRaisesError(exception, scm.update, options, (), [])
 
+  def testUpdateNotGit(self):
+    if not self.enabled:
+      return
+    options = self.Options()
+    scm = gclient_scm.CreateSCM(url=self.url, root_dir=self.root_dir,
+                                relpath=self.relpath)
+    git_path = gclient_scm.os.path.join(self.base_path, '.git')
+    os.rename(git_path, git_path + 'foo')
+    exception = \
+        '\n____ .\n' \
+        '\tPath is not a git repo. No .git dir.\n' \
+        '\tTo resolve:\n' \
+        '\t\trm -rf .\n' \
+        '\tAnd run gclient sync again\n'
+    self.assertRaisesError(exception, scm.update, options, (), [])
+
   def testRevinfo(self):
     if not self.enabled:
       return
     options = self.Options()
     scm = gclient_scm.CreateSCM(url=self.url, root_dir=self.root_dir,
                                 relpath=self.relpath)
     rev_info = scm.revinfo(options, (), None)
     self.assertEquals(rev_info, '069c602044c5388d2d15c3f875b057c852003458')
 
 
 if __name__ == '__main__':
   import unittest
   unittest.main()
 
 # vim: ts=2:sw=2:tw=80:et: