SassyBarista is a java implementation of a CSS preprocessor. The goal is that it will eventually be fully compatible with the SCSS syntax of SASS (http://sass-lang.com). It's based on a JavaCC grammar and is in a comparatively early stage, although some advanced features are already supported. Thereare still a few glitches that prevents some standard CSS files from parsing correctly, but I'm working on getting rid of them. I'd love to hear from you if you try it and encounter such parsing bugs. You can contact me at emil@quench.at.
If you need a way to parse css and manipulate it programatically this project might also fit nicely, since it was partly designed for that purpose. The java API should be rather straight forward to use directly.
The fact that it is meant to be usable as a css parser has some consequences for the design of the library. For example, the use of an AST is limited to expressions. This means that there is no total ordering of nodes outside of each scope. Whether or not this is a problem for you, I do not know. For my applications it is not.
Currently supported:
- Correctly parses most of the CSS specification. If you find examples of valid css that it can't process, I'd like to hear about it.
- Nesting of rules
- Variables (has to be defined in the global scope right now)
- Mixins (parameters are supported, although not keyword arguments, nesting rules within mixins works as expected)
- Selector inheritance (chaining and multiple, no partial substitutions)
- Basic arithmetic
- An @if statement, @else if and @else (no logical operators)
- Functions are supported, although currently no functions are implemented.
- Parent references
- Interpolation using #{} in selectors and property-names.
Planned:
- Improved error messages (currently javacc's default ParseException are used, which can be really confusing)
- Various output styles
- @for, @each and @while
- Keyword arguments to mixins
Not planned:
- Function directives (@function)
For samples of the capabilities, look in the testcases directory. It contains a .scss-file with the test case, and a manually controlled .css file. When running tests using "ant test" these are validated.
To build it you'll need to download JavaCC and specify the path to it in build.xml. Simply runt ant to build:
ant jar
You can then try ut using:
java -jar sassybarista.jar test.scss
Some relevant links: