For some reason the python comment regex that we used does not ignore
the line break at the end of a comment line.
This caused issues when parsing multi line assignments with comments
in between.
Use our own regex for comments to circumvent the issue. It was found
while trying to port the qtimageformats repo.
Added a pytest as well.
Change-Id: Ie4bbdac2d1e1c133bc787a995224d0bbd8238204
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>
e0a6e9f3aa