Test tree-sitter support for CSS

[alexr00]

Refs: #244442

• anyOS @mrleemurray
• anyOS @hawkticehurst
• anyOS @roblourens

Complexity: 2

Create Issue

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Setup

You need to enable tree sitter for CSS:

"editor.experimental.preferTreeSitter.css": true

Known differences in syntax highlighting

The big one is deprecated properties and values. The old CSS textmate grammar hardcoded a bunch deprecated tokens, We aren't going to support that with tree-sitter. So, some things that are deprecated and shown in red with textmate will not have that treatment with tree-sitter.

Testing

The goal of testing here is to identify places where we don't get the color right. When filing issues, please include a copy/pastable code snippet and the theme name. Pick 3-5 CSS files (even better if you pick examples of uncommon CSS) and do the following:

1. Open the file and see if you think any of syntax highlighting colors look off.
2. Open VS Code stable and open the same file there, if you see any differences in syntax highlighting, please file an issue, even if the new highlighting is better.

[alexr00]

Thank you all for the great bugs!