[WebUI] Fix 0-length unary term false positive in CSS presubmit.

chrome/browser/resources/web_dev_style/css_checker.py

Index: chrome/browser/resources/web_dev_style/css_checker.py
diff --git a/chrome/browser/resources/web_dev_style/css_checker.py b/chrome/browser/resources/web_dev_style/css_checker.py
index dc2355e4b9a5e139217bde4a6a7bbb81a0b18562..dbb4c5a480c1f9762df2e4ce851da272d815dd7a 100644
--- a/chrome/browser/resources/web_dev_style/css_checker.py
+++ b/chrome/browser/resources/web_dev_style/css_checker.py
@@ -124,11 +124,16 @@ class CSSChecker(object):
       return ' (replace with #%s)' % (h[0] + h[2] + h[4])
 
     hsl = r'hsl\([^\)]*(?:[, ]|(?<=\())(?:0?\.?)?0%'
-    zeros = (r'(?:^|\D)'
+    zeros = (r'^.*(?:^|\D)'

[Yoyo Zhou, 2012/04/20 01:31:40]

It seems like for the example "state0." in the test case, it'd be better to
change this \D to \W, or maybe the whole blob to \b.

              r'(?:\.0|0(?:\.0?|px|em|%|in|cm|mm|pc|pt|ex|deg|g?rad|m?s|k?hz))'
-             r'(?:\D|$)(?!\s*\{)')
-    def zero_length_values(line):
-      return (re.search(zeros, line) and not re.search(hsl, line))
+             r'(?:\D|$)(?=[^{}]+?}).*$')

[Yoyo Zhou, 2012/04/20 01:31:40]

The last } is literal, right? It's confusing without an escape.
Won't this regex just not match anything outside of any curly braces?

+    def zero_length_values(contents):
+      errors = []
+      for z in re.finditer(re.compile(zeros, re.MULTILINE), contents):
+        first_line = z.group(0).strip().splitlines()[0]
+        if not re.search(hsl, first_line):
+          errors.append('    ' + first_line)
+      return errors
 
     added_or_modified_files_checks = [
         { 'desc': 'Alphabetize properties and list vendor specific (i.e. '
@@ -178,6 +183,7 @@ class CSSChecker(object):
         { 'desc': 'Make all zero length terms (i.e. 0px) 0 unless inside of '
                   'hsl() or part of @keyframe.',
           'test': zero_length_values,
+          'multiline': True,
         },
     ]