Re-reland r245404 ("If the destination directory doesn't contain the desired repo, delete it")

tests/scm_unittest.py

Index: tests/scm_unittest.py
diff --git a/tests/scm_unittest.py b/tests/scm_unittest.py
index ff03c03e1b934ddd338d7e86ce1ce3acca62b8d6..2a1de53318e6c8ffa9e20dca21de70786bc8f38a 100755
--- a/tests/scm_unittest.py
+++ b/tests/scm_unittest.py
@@ -169,6 +169,18 @@ class RealGitSvnTest(fake_repos.FakeReposTestBase):
     self._capture(['reset', '--hard', 'HEAD^'])
     self.assertEquals(scm.GIT.GetGitSvnHeadRev(cwd=self.clone_dir), 1)
 
+  def testIsGitSvn(self):
+    if not self.enabled:
+      return
+    # Git-svn
+    self.assertTrue(scm.GIT.IsGitSvn(self.clone_dir))
+    # Pure git
+    git_dir = scm.os.path.join(self.FAKE_REPOS.git_root, 'repo_1')
+    self.assertFalse(scm.GIT.IsGitSvn(git_dir))
+    # Pure svn
+    svn_dir = scm.os.path.join(self.FAKE_REPOS.svn_checkout, 'trunk')
+    self.assertFalse(scm.GIT.IsGitSvn(svn_dir))
+
   def testParseGitSvnSha1(self):
     test_sha1 = 'a5c63ce8671922e5c59c0dea49ef4f9d4a3020c9'
     expected_output = test_sha1 + '\n'