Fix git cl checkout when no branch has issues.

TBR=machenbach@chromium.org
BUG=579182

Review URL: https://codereview.chromium.org/1878613003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@299843 0039d316-1c4b-4281-b951-d872f2087c98

git_cl.py

@@ -4550,10 +4550,10 @@ def CMDcheckout(parser, args):
   target_issue = str(issue_arg.issue)
 
   def find_issues(issueprefix):
-    key_and_issues = [x.split() for x in RunGit(
-        ['config', '--local', '--get-regexp', r'branch\..*\.%s' % issueprefix])
-        .splitlines()]
-    for key, issue in key_and_issues:
+    output = RunGit(['config', '--local', '--get-regexp',
+                     r'branch\..*\.%s' % issueprefix],
+                     error_ok=True)
+    for key, issue in [x.split() for x in output.splitlines()]:
       if issue == target_issue:
         yield re.sub(r'branch\.(.*)\.%s' % issueprefix, r'\1', key)
 

tests/git_cl_test.py

@@ -1180,6 +1180,19 @@ class TestGitCl(TestCase):
     self.calls = self._checkout_calls()
     self.assertEqual(1, git_cl.main(['checkout', '99999']))
 
+  def test_checkout_no_branch_issues(self):
+    """Tests git cl checkout <issue>."""
+    self.calls = [
+        ((['git', 'config', '--local', '--get-regexp',
+           'branch\\..*\\.rietveldissue'], ), '',
+         subprocess2.CalledProcessError(1, '', '', '', '')),
+        ((['git', 'config', '--local', '--get-regexp',
+           'branch\\..*\\.gerritissue'], ), '',
+         subprocess2.CalledProcessError(1, '', '', '', '')),
+
+    ]
+    self.assertEqual(1, git_cl.main(['checkout', '99999']))
+
 
 if __name__ == '__main__':
   git_cl.logging.basicConfig(