Beta

[akzhy]

• Add sourcemap support
• Show better CSS error and warning
• Bug fixes

[Copilot]

Pull request overview

This pull request introduces beta release changes for FlairJS, adding sourcemap support for CSS, improved error/warning messages, and several bug fixes. The changes include two breaking API modifications that are well-documented in the changelogs.

Changes:

• Added CSS sourcemap generation with proper file location reporting for errors and unused classnames
• Improved CSS error messages with detailed file locations and human-readable descriptions
• Enhanced unused classname detection with accurate line/column reporting via sourcemaps
• Breaking change: TransformOutput now always returns a value with a success property instead of returning null
• Breaking change: cssPreprocessor function signature changed to accept CssData object instead of plain string
• Updated dependencies: rolldown 1.0.0-beta.37 → 1.0.0-rc.4, @changesets/cli ^2.29.7 → ^2.29.8
• Removed Rolldown-based build configuration in favor of direct NAPI bindings
• Performance improvements through pre-compiled regex matchers for classname detection

Reviewed changes

Copilot reviewed 46 out of 48 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pnpm-workspace.yaml	Updated rolldown version to 1.0.0-rc.4
pnpm-lock.yaml	Updated lock file with new dependencies including sourcemap libraries
packages/core/src/utils.rs	New utility module with CSS error mapping and line/column tracking
packages/core/src/transform.rs	Updated transform logic with sourcemap support and unused classname detection
packages/core/src/parse_css.rs	Added sourcemap generation during CSS parsing with proper offset tracking
packages/core/src/update_attribute.rs	Added consumed classnames tracking and pre-compiled regex matchers
packages/core/src/style_tag.rs	Enhanced to track CSS source locations for better error reporting
packages/core/src/flair_property.rs	Added line/column tracking for flair property CSS
packages/core/Cargo.toml	Added new dependencies: data-encoding, lazy_static, parcel_sourcemap, sourcemap, smallvec
packages/shared/src/transform.ts	Updated to handle new CssData type and log unused classnames
packages/shared/src/plugin-core.ts	Updated cssPreprocessor signature
packages/vite-plugin/src/index.ts	Updated to use result.success check and CssData type
packages/rollup-plugin/src/index.ts	Updated to use result.success check and CssData type
packages/webpack-loader/src/index.ts	Updated to use result.success check and CssData type
packages/parcel-transformer/src/index.ts	Updated to use result.success check and CssData type
packages/core/index.d.ts	Added CssData and UnusedCss interfaces, updated TransformOutput
packages/core/package.json	Updated main/types to point to index.js/d.ts, removed Rolldown build scripts
packages/core/test/index.spec.ts	Added test for unused classname detection
.github/workflows/*.yml	Removed build:core-js step from CI workflows

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

Comments suppressed due to low confidence (1)

packages/core/test/index.spec.ts:45

• Inconsistent null check handling. Line 43-45 checks if (!result) and throws an error, but line 30 in the previous test directly uses result.code without this check. Since TransformOutput now always returns a value (as indicated by the breaking change), these null checks are unnecessary and should be removed for consistency across all tests.

    if (!result) {
      throw new Error('transformCode returned null or undefined')
    }

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