1# Copyright (c) 2012 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"""Presubmit script for Chromium WebUI resources. 6 7See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts 8for more details about the presubmit API built into gcl/git cl, and see 9http://www.chromium.org/developers/web-development-style-guide for the rules 10we're checking against here. 11""" 12 13# TODO(dbeam): Real CSS parser? pycss? http://code.google.com/p/pycss/ 14 15class CSSChecker(object): 16 def __init__(self, input_api, output_api, file_filter=None): 17 self.input_api = input_api 18 self.output_api = output_api 19 self.file_filter = file_filter 20 21 def RunChecks(self): 22 # We use this a lot, so make a nick name variable. 23 re = self.input_api.re 24 25 def _collapseable_hex(s): 26 return (len(s) == 6 and s[0] == s[1] and s[2] == s[3] and s[4] == s[5]) 27 28 def _is_gray(s): 29 return s[0] == s[1] == s[2] if len(s) == 3 else s[0:2] == s[2:4] == s[4:6] 30 31 def _remove_all(s): 32 return _remove_grit(_remove_ats(_remove_comments(s))) 33 34 def _remove_ats(s): 35 return re.sub(re.compile(r'@\w+.*?{(.*{.*?})+.*?}', re.DOTALL), '\\1', s) 36 37 def _remove_comments(s): 38 return re.sub(re.compile(r'/\*.*?\*/', re.DOTALL), '', s) 39 40 def _remove_grit(s): 41 grit_reg = r'<if[^>]+>.*?<\s*/\s*if[^>]*>|<include[^>]+>' 42 return re.sub(re.compile(grit_reg, re.DOTALL), '', s) 43 44 def _rgb_from_hex(s): 45 if len(s) == 3: 46 r, g, b = s[0] + s[0], s[1] + s[1], s[2] + s[2] 47 else: 48 r, g, b = s[0:2], s[2:4], s[4:6] 49 return int(r, base=16), int(g, base=16), int(b, base=16) 50 51 def alphabetize_props(contents): 52 errors = [] 53 for rule in re.finditer(r'{(.*?)}', contents, re.DOTALL): 54 semis = map(lambda t: t.strip(), rule.group(1).split(';'))[:-1] 55 rules = filter(lambda r: ': ' in r, semis) 56 props = map(lambda r: r[0:r.find(':')], rules) 57 if props != sorted(props): 58 errors.append(' %s;\n' % (';\n '.join(rules))) 59 return errors 60 61 def braces_have_space_before_and_nothing_after(line): 62 return re.search(r'(?:^|\S){|{\s*\S+\s*$', line) 63 64 def classes_use_dashes(line): 65 # Intentionally dumbed down version of CSS 2.1 grammar for class without 66 # non-ASCII, escape chars, or whitespace. 67 m = re.search(r'\.(-?[_a-zA-Z0-9-]+).*[,{]\s*$', line) 68 return (m and (m.group(1).lower() != m.group(1) or 69 m.group(1).find('_') >= 0)) 70 71 # Ignore single frames in a @keyframe, i.e. 0% { margin: 50px; } 72 frame_reg = r'\s*\d+%\s*{\s*[_a-zA-Z0-9-]+:(\s*[_a-zA-Z0-9-]+)+\s*;\s*}\s*' 73 def close_brace_on_new_line(line): 74 return (line.find('}') >= 0 and re.search(r'[^ }]', line) and 75 not re.match(frame_reg, line)) 76 77 def colons_have_space_after(line): 78 return re.search(r'(?<!data):(?!//)\S[^;]+;\s*', line) 79 80 def favor_single_quotes(line): 81 return line.find('"') >= 0 82 83 # Shared between hex_could_be_shorter and rgb_if_not_gray. 84 hex_reg = (r'#([a-fA-F0-9]{3}|[a-fA-F0-9]{6})(?=[^_a-zA-Z0-9-]|$)' 85 r'(?!.*(?:{.*|,\s*)$)') 86 def hex_could_be_shorter(line): 87 m = re.search(hex_reg, line) 88 return (m and _is_gray(m.group(1)) and _collapseable_hex(m.group(1))) 89 90 small_seconds = r'(?:^|[^_a-zA-Z0-9-])(0?\.[0-9]+)s(?!-?[_a-zA-Z0-9-])' 91 def milliseconds_for_small_times(line): 92 return re.search(small_seconds, line) 93 94 def no_data_uris_in_source_files(line): 95 return re.search(r'\(\s*\'?\s*data:', line) 96 97 def one_rule_per_line(line): 98 return re.search(r'[_a-zA-Z0-9-](?<!data):(?!//)[^;]+;\s*[^ }]\s*', line) 99 100 any_reg = re.compile(r':(?:-webkit-)?any\(.*?\)', re.DOTALL) 101 multi_sels = re.compile(r'(?:}[\n\s]*)?([^,]+,(?=[^{}]+?{).*[,{])\s*$', 102 re.MULTILINE) 103 def one_selector_per_line(contents): 104 errors = [] 105 for b in re.finditer(multi_sels, re.sub(any_reg, '', contents)): 106 errors.append(' ' + b.group(1).strip().splitlines()[-1:][0]) 107 return errors 108 109 def rgb_if_not_gray(line): 110 m = re.search(hex_reg, line) 111 return (m and not _is_gray(m.group(1))) 112 113 def suggest_ms_from_s(line): 114 ms = int(float(re.search(small_seconds, line).group(1)) * 1000) 115 return ' (replace with %dms)' % ms 116 117 def suggest_rgb_from_hex(line): 118 suggestions = ['rgb(%d, %d, %d)' % _rgb_from_hex(h.group(1)) 119 for h in re.finditer(hex_reg, line)] 120 return ' (replace with %s)' % ', '.join(suggestions) 121 122 def suggest_short_hex(line): 123 h = re.search(hex_reg, line).group(1) 124 return ' (replace with #%s)' % (h[0] + h[2] + h[4]) 125 126 hsl = r'hsl\([^\)]*(?:[, ]|(?<=\())(?:0?\.?)?0%' 127 zeros = (r'^.*(?:^|\D)' 128 r'(?:\.0|0(?:\.0?|px|em|%|in|cm|mm|pc|pt|ex|deg|g?rad|m?s|k?hz))' 129 r'(?:\D|$)(?=[^{}]+?}).*$') 130 def zero_length_values(contents): 131 errors = [] 132 for z in re.finditer(re.compile(zeros, re.MULTILINE), contents): 133 first_line = z.group(0).strip().splitlines()[0] 134 if not re.search(hsl, first_line): 135 errors.append(' ' + first_line) 136 return errors 137 138 added_or_modified_files_checks = [ 139 { 'desc': 'Alphabetize properties and list vendor specific (i.e. ' 140 '-webkit) above standard.', 141 'test': alphabetize_props, 142 'multiline': True, 143 }, 144 { 'desc': 'Start braces ({) end a selector, have a space before them ' 145 'and no rules after.', 146 'test': braces_have_space_before_and_nothing_after, 147 }, 148 { 'desc': 'Classes use .dash-form.', 149 'test': classes_use_dashes, 150 }, 151 { 'desc': 'Always put a rule closing brace (}) on a new line.', 152 'test': close_brace_on_new_line, 153 }, 154 { 'desc': 'Colons (:) should have a space after them.', 155 'test': colons_have_space_after, 156 }, 157 { 'desc': 'Use single quotes (\') instead of double quotes (") in ' 158 'strings.', 159 'test': favor_single_quotes, 160 }, 161 { 'desc': 'Use abbreviated hex (#rgb) when in form #rrggbb.', 162 'test': hex_could_be_shorter, 163 'after': suggest_short_hex, 164 }, 165 { 'desc': 'Use milliseconds for time measurements under 1 second.', 166 'test': milliseconds_for_small_times, 167 'after': suggest_ms_from_s, 168 }, 169 { 'desc': 'Don\'t use data URIs in source files. Use grit instead.', 170 'test': no_data_uris_in_source_files, 171 }, 172 { 'desc': 'One rule per line (what not to do: color: red; margin: 0;).', 173 'test': one_rule_per_line, 174 }, 175 { 'desc': 'One selector per line (what not to do: a, b {}).', 176 'test': one_selector_per_line, 177 'multiline': True, 178 }, 179 { 'desc': 'Use rgb() over #hex when not a shade of gray (like #333).', 180 'test': rgb_if_not_gray, 181 'after': suggest_rgb_from_hex, 182 }, 183 { 'desc': 'Make all zero length terms (i.e. 0px) 0 unless inside of ' 184 'hsl() or part of @keyframe.', 185 'test': zero_length_values, 186 'multiline': True, 187 }, 188 ] 189 190 results = [] 191 affected_files = self.input_api.AffectedFiles(include_deletes=False, 192 file_filter=self.file_filter) 193 files = [] 194 for f in affected_files: 195 # Remove all /*comments*/, @at-keywords, and grit <if|include> tags; we're 196 # not using a real parser. TODO(dbeam): Check alpha in <if> blocks. 197 file_contents = _remove_all('\n'.join(f.NewContents())) 198 files.append((f.LocalPath(), file_contents)) 199 200 # Only look at CSS files for now. 201 for f in filter(lambda f: f[0].endswith('.css'), files): 202 file_errors = [] 203 for check in added_or_modified_files_checks: 204 # If the check is multiline, it receieves the whole file and gives us 205 # back a list of things wrong. If the check isn't multiline, we pass it 206 # each line and the check returns something truthy if there's an issue. 207 if ('multiline' in check and check['multiline']): 208 check_errors = check['test'](f[1]) 209 if len(check_errors) > 0: 210 # There are currently no multiline checks with ['after']. 211 file_errors.append('- %s\n%s' % 212 (check['desc'], '\n'.join(check_errors).rstrip())) 213 else: 214 check_errors = [] 215 lines = f[1].splitlines() 216 for lnum in range(0, len(lines)): 217 line = lines[lnum] 218 if check['test'](line): 219 error = ' ' + line.strip() 220 if 'after' in check: 221 error += check['after'](line) 222 check_errors.append(error) 223 if len(check_errors) > 0: 224 file_errors.append('- %s\n%s' % 225 (check['desc'], '\n'.join(check_errors))) 226 if file_errors: 227 results.append(self.output_api.PresubmitPromptWarning( 228 '%s:\n%s' % (f[0], '\n\n'.join(file_errors)))) 229 230 if results: 231 # Add your name if you're here often mucking around in the code. 232 authors = ['dbeam@chromium.org'] 233 results.append(self.output_api.PresubmitNotifyResult( 234 'Was the CSS checker useful? Send feedback or hate mail to %s.' % 235 ', '.join(authors))) 236 237 return results 238