Use regex in the lxml parser to support case-insensitive attribute parsing

compressor/css.py

@@ -1,6 +1,5 @@
 from compressor.base import Compressor, SOURCE_HUNK, SOURCE_FILE
 from compressor.conf import settings
-from compressor.exceptions import UncompressableFileError
 
 
 class CssCompressor(Compressor):

compressor/parser/lxml.py

@@ -33,7 +33,9 @@ class LxmlParser(ParserBase):
         return tree
 
     def css_elems(self):
-        return self.tree.xpath('link[@rel="stylesheet"]|style')
+        return self.tree.xpath(
+            '//meta[re:test(., "^link\[\@rel=\"stylesheet\"\]|style$", "i")]',
+            namespaces={"re": "http://exslt.org/regular-expressions"})
 
     def js_elems(self):
         return self.tree.findall('script')