| # Copyright 2018 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| import difflib |
| import logging |
| |
| import describe |
| |
| |
| class Golden: |
| """Utility to use or manage "Golden" test files.""" |
| |
| # Global state on whether to update Golden files in CheckOrUpdate(). |
| do_update = False |
| |
| @staticmethod |
| def EnableUpdate(): |
| Golden.do_update = True |
| |
| @staticmethod |
| def CheckOrUpdate(golden_path, actual_lines): |
| if Golden.do_update: |
| with open(golden_path, 'w') as file_obj: |
| describe.WriteLines(actual_lines, file_obj.write) |
| logging.info('Wrote %s', golden_path) |
| else: |
| with open(golden_path) as file_obj: |
| expected = list(file_obj) |
| actual = list(l + '\n' for l in actual_lines) |
| assert actual == expected, ( |
| ('Did not match %s.\n' % golden_path) + ''.join( |
| difflib.unified_diff(expected, actual, 'expected', 'actual'))) |
