The CSS linter was pretty hard to reason about. It was
pretty flexible about certain things, but then it would
prevent seemingly innocuous code from getting checked in.
This commit overhauls the pretty-printer to be more composable,
where every object in the AST knows how to render itself. It
also cleans up a little bit of the pre_fluff/post_fluff logic
in the parser itself, so comments are more likely to be "attached"
to the AST node that make sense.
The linter is actually a bit more finicky about newlines, but
this is mostly a good thing, as most of the variations before
this commit were pretty arbitrary.
Tweaked by tabbott to not remove it from lister.py, linter_lib, and
friends, since those are intended to support both Python 2 and 3
(we're planning to extract them from the repository).
While it's sometimes nice to put a few selectors on the same line,
it is generally better to have a consistent way of formatting our
selectors, and most of our code up until now lists them vertically.
This change fixes the linter to enforce one selector per line, and
it cleans up the places in the CSS where we had multiple selectors
on the same line.
The advantages of one-per-line are as followers:
* cleaner diffs
* easier to see when multiple areas of the app may have the
same format
* less likely to go over 80 cols
* makes it more clear where we have deep nesting in the
individual selectors
* makes it easier for our linting tools to enforce
whitespace violations
This also fixed an old bug where we had ".landing_page h2, h4", which
sets "h4" styles outside of the landing page.
In this commit we modify our CSS parser not only to render the text from
a given CSS tokens produced but also enforce 4 space indentation on it.
Also we enforce some basic rules we would like our CSS to follow such as
* Always have "\n" in between the starting of body({) and body itself
and ending of the body and the closing of body(}).
* Use 4 space indents while having but something within the block
structure ( { .... } ).
* Have single space after ',' in between multiple selectors.
* Have only a single space in between selector and the starting of
block structure ({ ... }) if block structure starts on same line as
of selector.
eg. body {
body content here
}
Notice single space between 'body' and '{'.
Fixes: #1659.
This is a fairly major overhaul of the CSS parser to support
line numbers in error messages.
Basically, instead of passing "slices" of tokens around, we pass
indexes into the token arrays to all of our sub-parsers, which
allows them to have access to previous tokens in certain cases.
This is particularly important for errors where stuff is missing
(vs. being wrong).
In testing this out I found a few more places to catch errors.
`tools/lint-all` now calls the new `tools/check-css`
The css_parser library parsers CSS into a data structure
that remembers line numbers and columns of semantically
meaningful tokens and adjoining white space/tokens. It
is intended to be used for various linting tasks.
The file `tools/check-css` runs a few files through the
parser and makes sure they round trip. This has some value
right away, as files that fail to parse will cause an
exception to be thrown and thus alert developers to syntax
errors. We expect to grow this into more advanced linting
tasks eventually.
Steve Howell
rht
Aditya Bansal
Steve Howell
AZtheAsian
Sahil Dua