Plugin Directory: Skip the CSS source map in the production build

[derpaschi]

What

The grunt build task (run via npm run build:css) was still writing a css/style.css.map file, even though source maps aren't intended for the built/production CSS.

This adjusts the grunt-sass sourceMap option so the map is generated only for the local development tasks (grunt / grunt watch) and is skipped during grunt build:

sourceMap: 'build' !== process.argv[ 2 ],
omitSourceMapUrl: 'build' === process.argv[ 2 ],

Why

omitSourceMapUrl only strips the sourceMappingURL comment from style.css; it doesn't stop grunt-sass from writing the .map file itself. The previous condition evaluated to true during build, so a style.css.map was emitted on every production build and could end up committed alongside the compiled CSS. Keeping source maps for local development while leaving them out of the build keeps the production output clean and avoids accidentally shipping/committing the map.

Testing

• npm run build:css (i.e. grunt build) → no css/style.css.map is produced, and style.css contains no sourceMappingURL comment.
• grunt / grunt watch (local development) → source maps are still generated as before.

Notes

Small, build-tooling-only change with no effect on the theme's runtime output. Feedback welcome — happy to adjust if there's a preferred pattern for detecting the build task in this Gruntfile.

[github-actions]

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[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Updates the theme’s Grunt Sass configuration so source maps are disabled for build runs while remaining enabled for non-build invocations.

Changes:

• Gate sourceMap generation based on whether the build task is being executed.
• Adjust the inline comment to reflect the new behavior (source map + source map URL).

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