1# Copyright 2014 The Chromium Authors. All rights reserved. 2# Use of this source code is governed by a BSD-style license that can be 3# found in the LICENSE file. 4 5"""Utility functions for prompting user if changes automatically applied to some 6user-managed files are correct. 7""" 8 9import logging 10import os 11import webbrowser 12 13from difflib import HtmlDiff 14from tempfile import NamedTemporaryFile 15 16 17def PromptUserToAcceptDiff(old_text, new_text, prompt): 18 """Displays a difference in two strings (old and new file contents) to the 19 user and asks whether the new version is acceptable. 20 21 Args: 22 old_text: A string containing old file contents. 23 new_text: A string containing new file contents. 24 prompt: Text that should be displayed to the user, asking whether the new 25 file contents should be accepted. 26 27 Returns: 28 True is user accepted the changes or there were no changes, False otherwise. 29 """ 30 logging.info('Computing diff...') 31 if old_text == new_text: 32 logging.info('No changes detected') 33 return True 34 html_diff = HtmlDiff(wrapcolumn=80).make_file( 35 old_text.splitlines(), new_text.splitlines(), fromdesc='Original', 36 todesc='Updated', context=True, numlines=5) 37 temp = NamedTemporaryFile(suffix='.html', delete=False) 38 try: 39 temp.write(html_diff) 40 temp.close() # Close the file so the browser process can access it. 41 webbrowser.open('file://' + temp.name) 42 print prompt 43 response = raw_input('(Y/n): ').strip().lower() 44 finally: 45 temp.close() # May be called on already closed file. 46 os.remove(temp.name) 47 return response == 'y' or response == '' 48