grass 0.9.5

A near-feature-complete Sass compiler written purely in Rust
Documentation

grass

This crate aims to provide a high level interface for compiling Sass into plain CSS. It offers a very limited API, currently exposing only 2 functions.

In addition to a library, also included is a binary that is intended to act as an invisible replacement to the Sass commandline executable.

This crate aims to achieve complete feature parity with the dart-sass reference implementation. A deviation from the dart-sass implementation can be considered a bug except for in the following situations:

  • Error messages
  • Error spans
  • Certain aspects of the indented syntax
  • Potentially others in the future

Documentation
crates.io

Status

The large features remaining are

indented syntax
css imports
@use, @forward, and the module system
compressed output

This is in addition to dozens of smaller features, edge cases, and miscompilations.

Starting from grass v0.9.4, it is possible to compile Twitter Bootstrap 4 as well as bulma-scss.

The output is not exact byte-for-byte, and the remaining differences in output are tracked here.

Web Assembly

grass experimentally releases a WASM version of the library to npm, compiled using wasm-bindgen. To use grass in your JavaScript projects, just run npm install @connorskees/grass to your package.json. Better documentation for this version will be provided when the library becomes more stable.

Features

commandline

(enabled by default): build a binary using clap

random

(enabled by default): enable the builtin functions random([$limit]) and unique-id()

In the future this feature will be removed when it is no longer necessary to rely on rand for random numbers.

Testing

As much as possible this library attempts to follow the same philosophy for testing as rust-analyzer. Namely, all one should have to do is run cargo test to run all its tests. This library maintains a test suite distinct from the sass-spec, though it does include some spec tests verbatim. This has the benefit of allowing tests to be run without ruby as well as allowing the tests more granular than they are in the official spec.

Having said that, to run the official test suite,

git clone https://github.com/connorskees/grass --recursive
cd grass
cargo b --release
./sass-spec/sass-spec.rb -c './target/release/grass'

These numbers come from a default run of the Sass specification as shown above.

2020-07-04
PASSING: 2880
FAILING: 2213
TOTAL: 5093
2020-06-28
PASSING: 2821
FAILING: 2272
TOTAL: 5093
2020-06-23
PASSING: 2800
FAILING: 2293
TOTAL: 5093
2020-06-16
PASSING: 2489
FAILING: 2604
TOTAL: 5093
2020-06-07
PASSING: 2442
FAILING: 2651
TOTAL: 5093
2020-05-01
PASSING: 2193
FAILING: 2900
TOTAL: 5093
2020-04-21
PASSING: 2150
FAILING: 2943
TOTAL: 5093
2020-04-07
PASSING: 2031
FAILING: 3062
TOTAL: 5093
2020-04-01
PASSING: 1711
FAILING: 3382
TOTAL: 5093
2020-03-30
PASSING: 1685
FAILING: 3408
TOTAL: 5093
2020-03-23
PASSING: 1547
FAILING: 3546
TOTAL: 5093
2020-03-22
PASSING: 1442
FAILING: 3651
TOTAL: 5093
2020-02-24
PASSING: 1192
FAILING: 3901
TOTAL: 5093
2020-02-17
PASSING: 1115
FAILING: 3978
TOTAL: 5093
2020-02-10
PASSING: 475
FAILING: 4618
TOTAL: 5093
2020-02-03
PASSING: 242
FAILING: 4851
TOTAL: 5093
2020-01-27
PASSING: 186
FAILING: 4907
TOTAL: 5093
2020-01-20
PASSING: 143
FAILING: 4950
TOTAL: 5093