Add stop on first fail option

Similar to nosetests -x/--stop arg.

Author: jamesls

bin/jp-compliance

@@ -78,10 +78,11 @@ class ComplianceTestRunner(object):
         self.tests = tests
         self.jp_executable = exe
 
-    def run_tests(self):
+    def run_tests(self, stop_first_fail):
         for test_case in self._test_cases():
             if self._should_run(test_case):
-                self._run_test(test_case)
+                if not self._run_test(test_case) and stop_first_fail:
+                    return
 
     def _should_run(self, test_case):
         if not self.tests:
@@ -143,17 +144,21 @@ class ComplianceTestRunner(object):
             expected = test_case['result']
             if not actual == expected:
                 self._show_failure(actual, test_case)
+                return False
             else:
                 sys.stdout.write('.')
                 sys.stdout.flush()
+                return True
         else:
             error_type = test_case['error']
             # For errors, we expect the error type on stderr.
             if error_type not in stderr:
                 self._show_failure_for_error(stderr, test_case)
+                return False
             else:
                 sys.stdout.write('.')
                 sys.stdout.flush()
+                return True
 
     def _show_failure(self, actual, test_case):
         test_case['actual'] = json.dumps(actual)
@@ -218,13 +223,15 @@ def main():
                               'These values can then be used with the '
                               '"-t/--tests" argument.  If this argument is '
                               'specified, no tests will actually be run.'))
+    parser.add_argument('-s', '--stop-first-fail', action='store_true',
+                        help='Stop running tests after a single test fails.')
     args = parser.parse_args()
     runner = ComplianceTestRunner(args.exe, args.tests)
     if args.list:
         display_available_tests(runner.get_compliance_test_files())
     else:
         try:
-            runner.run_tests()
+            runner.run_tests(args.stop_first_fail)
         except Exception, e:
             sys.stderr.write(str(e))
             sys.stderr.write("\n")