Options.getJSON is not executed in a .css file that contains the same styles as another .css file

[MarcosViniciusPC]

My project has the following structure:

• components/
  index.css
  • header/
    index.css
    • B2B/
      index.css
      • shared/
        • menu/
          index.css
          • subcomponents/
            subMenuList.module.css
            menuList.module.css
    • B2B/
      index.css
      • shared/
        • menu/
          index.css
          • subcomponents/
            subMenuList.module.css
            menuList.module.css

For specific project reasons, the subMenu List.module.css file (B2B and B2C) contains styles that are identical to each other. The menuList.module.css file contains a slight variation: color: var(--primary-color) and color: var(--secondary-color).

In the build, getJSON passes through the components/header/B2C/shared/menu/subcomponents/subMenuList.module.css file, but not through components/header/B2B/shared/menu/subcomponents/subMenuList.module.css. This same behavior does not happen with components/header/[B2C|B2B]/shared/menu/subcomponents/menuList.module.css, the behavior I expect from all files. Is this a desired behavior for the build process or is it a bug?

[madyankin]

I traced through the code paths and don't see how postcss-modules itself would skip getJSON based on file content equality. The OnceExit hook runs once per CSS file that's piped through PostCSS, and the loader cache (tokensByFile) is keyed by file path, not content. Two files with identical bodies but different paths would each get a full pass.

The behaviour you're seeing is most likely upstream — e.g. a bundler dedupe (Vite/webpack content-hash) or your build pipeline running the file only once. Could you share:

1. The build tool you're using (postcss CLI, Vite, webpack, esbuild, etc.) and its config.
2. A minimal reproduction with just two identical-content .module.css files going through the postcss-modules plugin directly (not through a bundler), confirming the skip still happens.

If you can produce that I'll happily reopen and dig in; otherwise this is probably worth tracking against the bundler integration.