# Copyright (c) 2012 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.
"""Presubmit script for Chromium WebUI resources.
See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
for more details about the presubmit API built into gcl/git cl, and see
http://www.chromium.org/developers/web-development-style-guide for the rules
we're checking against here.
"""
# TODO(dbeam): Real CSS parser? https://github.com/danbeam/css-py/tree/css3
class CSSChecker(object):
def __init__(self, input_api, output_api, file_filter=None):
self.input_api = input_api
self.output_api = output_api
self.file_filter = file_filter
def RunChecks(self):
# We use this a lot, so make a nick name variable.
re = self.input_api.re
def _collapseable_hex(s):
return (len(s) == 6 and s[0] == s[1] and s[2] == s[3] and s[4] == s[5])
def _is_gray(s):
return s[0] == s[1] == s[2] if len(s) == 3 else s[0:2] == s[2:4] == s[4:6]
def _remove_all(s):
return _remove_grit(_remove_ats(_remove_comments(s)))
def _remove_ats(s):
at_reg = re.compile(r"""
@\w+.*?{ # @at-keyword selector junk {
(.*{.*?})+ # inner { curly } blocks, rules, and selector junk
.*?} # stuff up to the first end curly }""",
re.DOTALL | re.VERBOSE)
return at_reg.sub('\\1', s)
def _remove_comments(s):
return re.sub(re.compile(r'/\*.*?\*/', re.DOTALL), '', s)
def _remove_grit(s):
grit_reg = re.compile(r"""
<if[^>]+>.*?<\s*/\s*if[^>]*>| # <if> contents </if>
<include[^>]+> # <include>""",
re.DOTALL | re.VERBOSE)
return re.sub(grit_reg, '', s)
def _rgb_from_hex(s):
if len(s) == 3:
r, g, b = s[0] + s[0], s[1] + s[1], s[2] + s[2]
else:
r, g, b = s[0:2], s[2:4], s[4:6]
return int(r, base=16), int(g, base=16), int(b, base=16)
def _strip_prefix(s):
return re.sub(r'^-(?:o|ms|moz|khtml|webkit)-', '', s)
def alphabetize_props(contents):
errors = []
for rule in re.finditer(r'{(.*?)}', contents, re.DOTALL):
semis = map(lambda t: t.strip(), rule.group(1).split(';'))[:-1]
rules = filter(lambda r: ': ' in r, semis)
props = map(lambda r: r[0:r.find(':')], rules)
if props != sorted(props):
errors.append(' %s;\n' % (';\n '.join(rules)))
return errors
def braces_have_space_before_and_nothing_after(line):
brace_space_reg = re.compile(r"""
(?:^|\S){| # selector{ or selector\n{ or
{\s*\S+\s* # selector { with stuff after it
$ # must be at the end of a line""",
re.VERBOSE)
return brace_space_reg.search(line)
def classes_use_dashes(line):
# Intentionally dumbed down version of CSS 2.1 grammar for class without
# non-ASCII, escape chars, or whitespace.
class_reg = re.compile(r"""
\.(-?[\w-]+).* # ., then maybe -, then alpha numeric and -
[,{]\s*$ # selectors should end with a , or {""",
re.VERBOSE)
m = class_reg.search(line)
if not m:
return False
class_name = m.group(1)
return class_name.lower() != class_name or '_' in class_name
def close_brace_on_new_line(line):
# Ignore single frames in a @keyframe, i.e. 0% { margin: 50px; }
frame_reg = re.compile(r"""
\s*\d+%\s*{ # 50% {
\s*[\w-]+: # rule:
(\s*[\w-]+)+\s*; # value;
\s*}\s* # }""",
re.VERBOSE)
return ('}' in line and re.search(r'[^ }]', line) and
not frame_reg.match(line))
def colons_have_space_after(line):
colon_space_reg = re.compile(r"""
(?<!data) # ignore data URIs
:(?!//) # ignore url(http://), etc.
\S[^;]+;\s* # only catch one-line rules for now""",
re.VERBOSE)
return colon_space_reg.search(line)
def favor_single_quotes(line):
return '"' in line
# Shared between hex_could_be_shorter and rgb_if_not_gray.
hex_reg = re.compile(r"""
\#([a-fA-F0-9]{3}|[a-fA-F0-9]{6}) # pound followed by 3 or 6 hex digits
(?=[^\w-]|$) # no more alphanum chars or at EOL
(?!.*(?:{.*|,\s*)$) # not in a selector""",
re.VERBOSE)
def hex_could_be_shorter(line):
m = hex_reg.search(line)
return (m and _is_gray(m.group(1)) and _collapseable_hex(m.group(1)))
def rgb_if_not_gray(line):
m = hex_reg.search(line)
return (m and not _is_gray(m.group(1)))
small_seconds_reg = re.compile(r"""
(?:^|[^\w-]) # start of a line or a non-alphanumeric char
(0?\.[0-9]+)s # 1.0s
(?!-?[\w-]) # no following - or alphanumeric chars""",
re.VERBOSE)
def milliseconds_for_small_times(line):
return small_seconds_reg.search(line)
def suggest_ms_from_s(line):
ms = int(float(small_seconds_reg.search(line).group(1)) * 1000)
return ' (replace with %dms)' % ms
def no_data_uris_in_source_files(line):
return re.search(r'\(\s*\'?\s*data:', line)
def one_rule_per_line(line):
one_rule_reg = re.compile(r"""
[\w-](?<!data): # a rule: but no data URIs
(?!//)[^;]+; # value; ignoring colons in protocols://
\s*[^ }]\s* # any non-space after the end colon""",
re.VERBOSE)
return one_rule_reg.search(line)
def pseudo_elements_double_colon(contents):
pseudo_elements = ['after',
'before',
'calendar-picker-indicator',
'color-swatch',
'color-swatch-wrapper',
'date-and-time-container',
'date-and-time-value',
'datetime-edit',
'datetime-edit-ampm-field',
'datetime-edit-day-field',
'datetime-edit-hour-field',
'datetime-edit-millisecond-field',
'datetime-edit-minute-field',
'datetime-edit-month-field',
'datetime-edit-second-field',
'datetime-edit-text',
'datetime-edit-week-field',
'datetime-edit-year-field',
'details-marker',
'file-upload-button',
'first-letter',
'first-line',
'inner-spin-button',
'input-placeholder',
'input-speech-button',
'keygen-select',
'media-slider-container',
'media-slider-thumb',
'meter-bar',
'meter-even-less-good-value',
'meter-inner-element',
'meter-optimum-value',
'meter-suboptimum-value',
'progress-bar',
'progress-inner-element',
'progress-value',
'resizer',
'scrollbar',
'scrollbar-button',
'scrollbar-corner',
'scrollbar-thumb',
'scrollbar-track',
'scrollbar-track-piece',
'search-cancel-button',
'search-decoration',
'search-results-button',
'search-results-decoration',
'selection',
'slider-container',
'slider-runnable-track',
'slider-thumb',
'textfield-decoration-container',
'validation-bubble',
'validation-bubble-arrow',
'validation-bubble-arrow-clipper',
'validation-bubble-heading',
'validation-bubble-message',
'validation-bubble-text-block']
pseudo_reg = re.compile(r"""
(?<!:): # a single colon, i.e. :after but not ::after
([a-zA-Z-]+) # a pseudo element, class, or function
(?=[^{}]+?{) # make sure a selector, not inside { rules }""",
re.MULTILINE | re.VERBOSE)
errors = []
for p in re.finditer(pseudo_reg, contents):
pseudo = p.group(1).strip().splitlines()[0]
if _strip_prefix(pseudo.lower()) in pseudo_elements:
errors.append(' :%s (should be ::%s)' % (pseudo, pseudo))
return errors
def one_selector_per_line(contents):
any_reg = re.compile(r"""
:(?:-webkit-)?any\(.*?\) # :-webkit-any(a, b, i) selector""",
re.DOTALL | re.VERBOSE)
multi_sels_reg = re.compile(r"""
(?:}\s*)? # ignore 0% { blah: blah; }, from @keyframes
([^,]+,(?=[^{}]+?{) # selector junk {, not in a { rule }
.*[,{])\s*$ # has to end with , or {""",
re.MULTILINE | re.VERBOSE)
errors = []
for b in re.finditer(multi_sels_reg, re.sub(any_reg, '', contents)):
errors.append(' ' + b.group(1).strip().splitlines()[-1:][0])
return errors
def suggest_rgb_from_hex(line):
suggestions = ['rgb(%d, %d, %d)' % _rgb_from_hex(h.group(1))
for h in re.finditer(hex_reg, line)]
return ' (replace with %s)' % ', '.join(suggestions)
def suggest_short_hex(line):
h = hex_reg.search(line).group(1)
return ' (replace with #%s)' % (h[0] + h[2] + h[4])
def zero_length_values(contents):
hsl_reg = re.compile(r"""
hsl\([^\)]* # hsl(<maybe stuff>
(?:[, ]|(?<=\()) # a comma or space not followed by a (
(?:0?\.?)?0% # some equivalent to 0%""",
re.VERBOSE)
zeros_reg = re.compile(r"""
^.*(?:^|\D) # start/non-number
(?:\.0|0(?:\.0? # .0, 0, or 0.0
|px|em|%|in|cm|mm|pc|pt|ex|deg|g?rad|m?s|k?hz)) # a length unit
(?:\D|$) # non-number/end
(?=[^{}]+?}).*$ # only { rules }""",
re.MULTILINE | re.VERBOSE)
errors = []
for z in re.finditer(zeros_reg, contents):
first_line = z.group(0).strip().splitlines()[0]
if not hsl_reg.search(first_line):
errors.append(' ' + first_line)
return errors
# NOTE: Currently multi-line checks don't support 'after'. Instead, add
# suggestions while parsing the file so another pass isn't necessary.
added_or_modified_files_checks = [
{ 'desc': 'Alphabetize properties and list vendor specific (i.e. '
'-webkit) above standard.',
'test': alphabetize_props,
'multiline': True,
},
{ 'desc': 'Start braces ({) end a selector, have a space before them '
'and no rules after.',
'test': braces_have_space_before_and_nothing_after,
},
{ 'desc': 'Classes use .dash-form.',
'test': classes_use_dashes,
},
{ 'desc': 'Always put a rule closing brace (}) on a new line.',
'test': close_brace_on_new_line,
},
{ 'desc': 'Colons (:) should have a space after them.',
'test': colons_have_space_after,
},
{ 'desc': 'Use single quotes (\') instead of double quotes (") in '
'strings.',
'test': favor_single_quotes,
},
{ 'desc': 'Use abbreviated hex (#rgb) when in form #rrggbb.',
'test': hex_could_be_shorter,
'after': suggest_short_hex,
},
{ 'desc': 'Use milliseconds for time measurements under 1 second.',
'test': milliseconds_for_small_times,
'after': suggest_ms_from_s,
},
{ 'desc': "Don't use data URIs in source files. Use grit instead.",
'test': no_data_uris_in_source_files,
},
{ 'desc': 'One rule per line (what not to do: color: red; margin: 0;).',
'test': one_rule_per_line,
},
{ 'desc': 'One selector per line (what not to do: a, b {}).',
'test': one_selector_per_line,
'multiline': True,
},
{ 'desc': 'Pseudo-elements should use double colon (i.e. ::after).',
'test': pseudo_elements_double_colon,
'multiline': True,
},
{ 'desc': 'Use rgb() over #hex when not a shade of gray (like #333).',
'test': rgb_if_not_gray,
'after': suggest_rgb_from_hex,
},
{ 'desc': 'Make all zero length terms (i.e. 0px) 0 unless inside of '
'hsl() or part of @keyframe.',
'test': zero_length_values,
'multiline': True,
},
]
results = []
affected_files = self.input_api.AffectedFiles(include_deletes=False,
file_filter=self.file_filter)
files = []
for f in affected_files:
# Remove all /*comments*/, @at-keywords, and grit <if|include> tags; we're
# not using a real parser. TODO(dbeam): Check alpha in <if> blocks.
file_contents = _remove_all('\n'.join(f.NewContents()))
files.append((f.LocalPath(), file_contents))
# Only look at CSS files for now.
for f in filter(lambda f: f[0].endswith('.css'), files):
file_errors = []
for check in added_or_modified_files_checks:
# If the check is multiline, it receieves the whole file and gives us
# back a list of things wrong. If the check isn't multiline, we pass it
# each line and the check returns something truthy if there's an issue.
if ('multiline' in check and check['multiline']):
assert not 'after' in check
check_errors = check['test'](f[1])
if len(check_errors) > 0:
file_errors.append('- %s\n%s' %
(check['desc'], '\n'.join(check_errors).rstrip()))
else:
check_errors = []
lines = f[1].splitlines()
for lnum, line in enumerate(lines):
if check['test'](line):
error = ' ' + line.strip()
if 'after' in check:
error += check['after'](line)
check_errors.append(error)
if len(check_errors) > 0:
file_errors.append('- %s\n%s' %
(check['desc'], '\n'.join(check_errors)))
if file_errors:
results.append(self.output_api.PresubmitPromptWarning(
'%s:\n%s' % (f[0], '\n\n'.join(file_errors))))
if results:
# Add your name if you're here often mucking around in the code.
authors = ['dbeam@chromium.org']
results.append(self.output_api.PresubmitNotifyResult(
'Was the CSS checker useful? Send feedback or hate mail to %s.' %
', '.join(authors)))
return results