Duplicate @media queries trigger an AssertionError #46
Description
I have the following HTML file with the same @media query appearing twice:
<!-- /tmp/example.html -->
<html>
<head>
<style>
@media screen and (min-width: 600px) { p { display: none; } }
@media screen and (min-width: 600px) { p { display: none; } }
</style>
</head>
<body>
<p>Hello world</p>
</body>
</html>If I run the following script:
from mincss.processor import Processor
p = Processor()
p.process('file:///tmp/example.html')I get an AssertionError:
$ python testcase.py
Traceback (most recent call last):
File "testcase.py", line 7, in <module>
p.process('file:///tmp/example.html')
File "/Users/chana/.virtualenvs/tempenv-24ba183892d9d/lib/python3.6/site-packages/mincss/processor.py", line 152, in process
processed = self._process_content(content, self._bodies)
File "/Users/chana/.virtualenvs/tempenv-24ba183892d9d/lib/python3.6/site-packages/mincss/processor.py", line 380, in _process_content
assert old in content, old
AssertionError: @media screen and (min-width: 600px) { p { display: none; } }The expected behaviour in this case would be:
- If the HTML contains a
<p>tag, the CSS is reduced to one instance of the @media query - If the HTML does not contain a
<p>tag, both instances of the @media query are removed
I hit this from a weird corner case in my build system where it sometimes renders duplicate CSS selectors, and then I pass it into mincss for extra processing. I have a fairly easy workaround – this could be considered a case of “garbage in, garbage out” – but having tracked it down, I thought I might as well report it.
Version info:
$ python --version
Python 3.6.0
$ pip freeze
appdirs==1.4.0
cssselect==1.0.1
lxml==3.7.3
mincss==0.11.2
packaging==16.8
pyparsing==2.1.10
six==1.10.0