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When providing `--css-modules insertHashHere` microbundle will treat all CSS files as CSS modules

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
javascript
Domain
build-system, cli

Research direction

Start in src/lib/css-modules.js around the referenced line and reproduce the behavior with --css-modules true, a custom hash pattern, and --no-css-modules. Done means a custom hash changes generated CSS-module signatures without making every CSS file a module, while the documented flag behaviors remain distinct.

Written by the indexing model from the issue text.

Description

Microbundle supports providing a custom hash generator name for CSS modules by providing --css-modules insertHashPatternHere (eg.: --css-modules _[hash:base64:5].

The Bug

But then Microbundle will also treat all CSS files as CSS modules, instead of just changing the generated signature of the actual CSS modules.

By the documentation, all CSS files should be considered a CSS module if a flag --css-modules true is provided.

Possibly source of the Bug

The bug seems to originate on https://github.com/developit/microbundle/blob/b1a637486234a2ae784ccf0c512321e2d3efef7c/src/lib/css-modules.js#L8 where it only considers the "should only suffix modules" when the option null is being passed.

The caveats

I suppose the --css-modules flag should only support null, true and false (Default Behaviour (Only when suffix), Enforce AutoCSS modules, Disable CSS modules completely).

Since there is the flag --no-css-modules there should be one for specifying the hash too. For example --css-modules-hash _[hash:base64:5].

This would also avoid confusion since it is not documented in the README that using a custom hash would enforce CSS modules.

I would be more than happy to provide a patch 😄

Dominant language
JavaScript
Stars
8.1k
Forks
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PR merge metrics
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