CSS Minification - 0 followed by a unit is rewritten to 0 without a unit. #1538
Description
I ran into this today with mod_pagespeed 1.11.33.4-0 that is packaged in cPanel experimental repo.
When using CSS minifier, 0 followed by a unit, such as 0px
, is re-written into 0
without a unit. This breaks some CSS directives that always require a unit. Example is a dynamic construction of CSS that drops a 0px
into a calc()
when an offset is not required.
Example:
left: calc(50% - $offset);
Since its not always used, $offset
is set to 0px
by default, which renders as:
left: calc(50% - 0px);
Upon minification, Pagespeed truncates the px
resulting in:
left: calc(50% - 0);
This is invalid and causes errors. Besides Pagespeed, this issue seems to be found in other minification applications as well. Is there any possibility to always include the unit of measurement? The spec claims unit is optional, so perhaps there should be a config for it rather than assuming "no unit" on rewrite: https://www.w3.org/TR/css3-values/#lengths
Thanks.