Feat: Automatically Discover StyleX Aliases from Configuration Files (Rebased PR of #810)

[nmn]

What changed / motivation ?

This a rebased implementation of #810 with bug fixes.

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[Feature] Automatically Discover StyleX Aliases from Configuration Files

Linked Issues

Fixes #765

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Overview

This PR enhances the StyleX Babel plugin to automatically discover alias configurations from Node.js native imports (package.json), tsconfig.json, and deno.json. It ensures normalized paths for cross-platform compatibility and maintains backward compatibility with existing manual configurations.

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Implementation Details

• JSON5 Parser: Handles configuration files with comments or trailing commas.
• Alias Discovery:
  • Parses package.json for Node.js native subpath imports (aliases with # prefix).
  • Parses tsconfig.json for compilerOptions.paths and resolves paths relative to baseUrl.
  • Parses deno.json for the imports field.
• Merge Configurations:
  • Combines configurations from all sources:
    Manual > package.json > tsconfig.json > deno.json.
• Code Reuse:
  • Replaced redundant findProjectRoot with getPackageNameAndPath for project root discovery.
• Normalized Paths:
  • Standardizes path separators for cross-platform compatibility.
• Error Handling:
  • Gracefully handles missing or malformed configuration files.

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Test Coverage

The following scenarios are tested:

1. Alias Discovery:

• Node.js native imports from package.json (subpath imports).
• Aliases from tsconfig.json paths.
• Aliases from deno.json imports.

2. Configuration Merging:

• Merges aliases from all sources with correct priority.

3. Manual Overrides:

• Ensures manual alias configurations take precedence over discovered aliases.

4. Error Handling:

• Handles missing or invalid configuration files gracefully.

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Code Changes

1. state-manager.js (Alias Discovery)

• Updated Functionality:
  • loadAliases:
    • Now supports Node.js native imports and deno.json.
    • Removed custom stylex.aliases support.
    • Simplified project root discovery using getPackageNameAndPath.
• Added support for deno.json imports.

2. stylex-transform-alias-config-test.js

• Updated Unit Tests:
  • Tests for Node.js native imports discovery.
  • Tests for deno.json imports.
  • Tests for merged configuration from all sources.
  • Tests for proper handling of invalid configurations.

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Potential Future Improvements

1. Enhanced Test Cases:

   • Complex alias patterns with wildcards.
   • Nested directory structures.
   • Edge cases in path resolution.

2. Additional Features:

   • Support for other configuration sources like Webpack config.
   • More granular control over alias resolution priorities.

3. Performance Optimizations:

   • Caching of discovered configurations.
   • Smarter file system traversal.

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Pre-flight Checklist

• I have read the Contribution Guidelines.
• Performed a self-review of my code.
• Added tests for the new functionality.
• Verified cross-platform compatibility.
• Ensured backward compatibility with existing configurations.

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Feedback

Feedback is welcome, particularly for:

• Additional test cases to consider.
• Improvements to performance or alias resolution edge cases.

[github-actions]

workflow: benchmarks/size

Comparison of minified (terser) and compressed (brotli) size results, measured in bytes. Smaller is better.

@stylexjs/scripts@0.10.1 size:compare
./size-compare.js /tmp/tmp.FIus1Kf4Aj /tmp/tmp.m90PSOJePF

Results	Base	Patch	Ratio
stylex/lib/stylex.js
· compressed	950	950	1.00
· minified	3,051	3,051	1.00
stylex/lib/StyleXSheet.js
· compressed	1,266	1,266	1.00
· minified	3,776	3,776	1.00
rollup-example/.build/bundle.js
· compressed	567,170	567,170	1.00
· minified	10,232,457	10,232,457	1.00
rollup-example/.build/stylex.css
· compressed	100,628	100,628	1.00
· minified	755,718	755,718	1.00

[mellyeliu]

there's a lot of repeated code within these 3 try blocks - can we refactor to use a loop on ["package.json", "tsconfig.json", "deno.json"], will also make it more maintainable if we want to add support to other configs as follow ups

[mellyeliu]

nit: we should consider moving some of this logic to a separate files utils, there's some path functions in the cache.js utils that I also want to extract