blob: 726f71ea95f1c7bed8bd096dda9d8a72b7a34340 [file] [log] [blame]
# Copyright 2014 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
def RegexCheck(re, line_number, line, regex, msg):
"""Searches for |regex| in |line| to check for a particular style
violation, returning a message like the one below if the regex matches.
The |regex| must have exactly one capturing group so that the relevant
part of |line| can be highlighted. If more groups are needed, use
"(?:...)" to make a non-capturing group. Sample message:
line 6: Use var instead of const.
const foo = bar();
^^^^^
"""
def _highlight(match):
"""Takes a start position and a length, and produces a row of '^'s to
highlight the corresponding part of a string.
"""
return match.start(1) * ' ' + (match.end(1) - match.start(1)) * '^'
match = re.search(regex, line)
if match:
assert len(match.groups()) == 1
return ' line %d: %s\n%s\n%s' % (line_number, msg, line, _highlight(match))
return ''