Improved coverage with more tests: parse_args

Coverage at 66% according to coveragy.py

Author: palimondo

benchmark/scripts/compare_perf_tests.py

@@ -253,9 +253,11 @@ def _column_widths(self):
                        changed + self.comparator.unchanged)
         comparisons += self.comparator.added + self.comparator.removed
 
-        widths = map(lambda columns: map(len, columns),
-                     [PerformanceTestResult.header, ResultComparison.header] +
-                     [c.values() for c in comparisons])
+        widths = [
+            map(len, columns) for columns in
+            [PerformanceTestResult.header, ResultComparison.header] +
+            [c.values() for c in comparisons]
+        ]
 
         def max_widths(maximum, widths):
             return tuple(map(max, zip(maximum, widths)))
@@ -375,8 +377,8 @@ def table(title, results, speedup_color):
             ]))
 
 
-def main():
-
+def parse_args(args):
+    """Parse command line arguments and set default values."""
     parser = argparse.ArgumentParser(description='Compare Performance tests.')
     parser.add_argument('--old-file',
                         help='Baseline performance test suite (csv file)',
@@ -396,11 +398,15 @@ def main():
     parser.add_argument('--old-branch',
                         help='Name of the old branch', default='OLD_MIN')
     parser.add_argument('--delta-threshold',
-                        help='Delta threshold. Default 0.05.', default='0.05')
+                        help='Delta threshold. Default 0.05.',
+                        type=float, default=0.05)
+    return parser.parse_args(args)
 
-    args = parser.parse_args()
+
+def main():
+    args = parse_args(sys.argv[1:])
     comparator = TestComparator(args.old_file, args.new_file,
-                                float(args.delta_threshold))
+                                args.delta_threshold)
     formatter = ReportFormatter(comparator, args.old_branch, args.new_branch,
                                 args.changes_only)
 

benchmark/scripts/test_compare_perf_tests.py

@@ -21,6 +21,7 @@
 from compare_perf_tests import PerformanceTestResult
 from compare_perf_tests import ResultComparison
 from compare_perf_tests import TestComparator
+from compare_perf_tests import parse_args
 
 
 class TestPerformanceTestResult(unittest.TestCase):
@@ -225,5 +226,57 @@ def names(tests):
         self.assertEquals(tc.decreased, [])
 
 
+class Test_parse_args(unittest.TestCase):
+    required = ['--old-file', 'old.log', '--new-file', 'new.log']
+
+    def test_required_input_arguments(self):
+        args = parse_args(self.required)
+        self.assertEquals(args.old_file, 'old.log')
+        self.assertEquals(args.new_file, 'new.log')
+        self.assertRaises(SystemExit, parse_args, [])
+
+    def test_format_argument(self):
+        self.assertEquals(
+            parse_args(self.required + ['--format', 'markdown']).format,
+            'markdown')
+        self.assertEquals(
+            parse_args(self.required + ['--format', 'git']).format, 'git')
+        self.assertEquals(
+            parse_args(self.required + ['--format', 'html']).format, 'html')
+        self.assertRaises(SystemExit, parse_args,
+                          self.required + ['--format', 'bogus'])
+
+    def test_delta_threshold_argument(self):
+        # default value
+        args = parse_args(self.required)
+        self.assertEquals(args.delta_threshold, 0.05)
+        # float parsing
+        args = parse_args(self.required + ['--delta-threshold', '0.1'])
+        self.assertEquals(args.delta_threshold, 0.1)
+        args = parse_args(self.required + ['--delta-threshold', '1'])
+        self.assertEquals(args.delta_threshold, 1.0)
+        args = parse_args(self.required + ['--delta-threshold', '.2'])
+        self.assertEquals(args.delta_threshold, 0.2)
+        self.assertRaises(SystemExit, parse_args,
+                          self.required + ['--delta-threshold', '2,2'])
+
+    def test_changes_only_argument(self):
+        self.assertFalse(parse_args(self.required).changes_only)
+        self.assertTrue(parse_args(self.required +
+                                   ['--changes-only']).changes_only)
+
+    def test_branch_arguments(self):
+        # default value
+        args = parse_args(self.required)
+        self.assertEquals(args.new_branch, 'NEW_MIN')
+        self.assertEquals(args.old_branch, 'OLD_MIN')
+        # user specified
+        args = parse_args(
+            self.required + ['--old-branch', 'master',
+                             '--new-branch', 'amazing-optimization'])
+        self.assertEquals(args.old_branch, 'master')
+        self.assertEquals(args.new_branch, 'amazing-optimization')
+
+
 if __name__ == '__main__':
     unittest.main()