Allow differing leading/trailing whitespace when checking test output

Author: briancroom

Tests/Functional/xctest_checker/tests/test_compare.py

@@ -54,5 +54,15 @@ def test_includes_file_name_and_line_of_expected_in_error(self):
 
         self.assertIn("{}:{}:".format(expected, 2), cm.exception.message)
 
+    def test_matching_ignores_leading_and_trailing_whitespace(self):
+        actual = _tmpfile('foo\nbar\nbaz\n')
+        expected = _tmpfile('c:  foo\nc: bar \nc: baz\n')
+        compare.compare(actual, expected, check_prefix='c:')
+
+    def test_can_explicitly_match_leading_and_trailing_whitespace(self):
+        actual = _tmpfile('foo\n bar\nbaz \n')
+        expected = _tmpfile('c: foo\nc: ^ bar \nc: baz $\n')
+        compare.compare(actual, expected, check_prefix='c:')
+
 if __name__ == "__main__":
     unittest.main()

Tests/Functional/xctest_checker/xctest_checker/compare.py

@@ -28,8 +28,10 @@ def _expected_lines_and_line_numbers(path, check_prefix):
     with open(path) as f:
         for line_number, line in enumerate(f):
             if line.startswith(check_prefix):
-                yield line[len(check_prefix):], line_number+1
+                yield line[len(check_prefix):].strip(), line_number+1
 
+def _add_whitespace_leniency(original_regex):
+    return "^ *" + original_regex + " *$"
 
 def compare(actual, expected, check_prefix):
     """
@@ -52,7 +54,7 @@ def compare(actual, expected, check_prefix):
 
         (expected_line, expectation_source_line_number) = expected_line_and_line_number
 
-        if not re.match(expected_line, actual_line):
+        if not re.match(_add_whitespace_leniency(expected_line), actual_line):
             raise AssertionError('Actual line did not match the expected '
                                  'regular expression.\n'
                                  '{}:{}: Actual: {}\n'

Tests/Functional/xctest_checker/xctest_checker/main.py

@@ -23,12 +23,14 @@ def main():
     parser.add_argument('expected', help='A path to a file containing the '
                                          'expected output of an XCTest run.')
     parser.add_argument('-p', '--check-prefix',
-                        default='// CHECK: ',
+                        default='// CHECK:',
                         help='{prog} checks actual output against expected '
                              'output. By default, {prog} only checks lines '
-                             'that are prefixed with "// CHECK: ". This '
+                             'that are prefixed with "// CHECK:". This '
                              'option can be used to change that '
-                             'prefix.'.format(prog=parser.prog))
+                             'prefix. Leading and trailing whitespace is '
+                             'ignored unless the check line contains explicit '
+                             '^ or $ characters'.format(prog=parser.prog))
     args = parser.parse_args()
     compare.compare(args.actual, args.expected, args.check_prefix)