Filter options for Vite built-in transformation plugins

[brawaru]

Description

I have developed a plugin for Rollup that automatically compiles ICU MessageFormat messages stored in JSON files of specific schema into an AST. It makes it possible to not bring a huge parser into runtime, which reduces bundle size and improves performance when interpreting the messages. The plugin is @braw/rollup-plugin-icu-messages.

Unfortunately, Vite's built-in JSON parsing plugin does not include any options to exclude specific files from parsing, which creates a conflict, since either Vite or icu-messages finds the file already parsed and fails to process it. In Rollup this conflict could've been easily solved by passing exclude: ['glob/to/locale-files/*.json'] option. Unfortunately, there is no such option in Vite.

Suggested solution

Provide filter options (include, exclude) like in common Rollup plugins to exclude or include certain files for transformation, like this:

import { defineConfig } from 'vite'

export default defineConfig({
  json: {
    exclude: ['./src/locales/*.json'], // <- makes vite:json avoid transformation of any JSON files in `./src/locales`.
  },
})

Alternative

• Use alternative format. This creates issue with translation management platforms (like Crowdin) that except certain file format to properly parse it. I believe Crowdin has added option where you can override the format, but it requires additional configuration. And there is a lot of configuration already.
• Compile files using formajs compile (from formatjs/cli). This won't work with non-JSON files and creates an intermediate step, which is annoying to deal with (you will have two sets of locale files). It makes sense to pre-compile locale files during the build, it's easy and would be convenient if it all just worked.
• Wrap plugins. I anticipated something like this could happen (where there would be a stubborn plugin that will not allow you to exclude certain file formats) and tried to create a wrapping plugin that relies on buildStart hook of Rollup to then iterate over all plugins and wrap/remove their transform or load methods. Unfortunately, this hook does not work in Vite! Or at least I don't have a slightest clue how to make it work, enforce, apply, nothing have worked for me: plugins is either undefined or simply empty.
• Annoy (/j /lh) Rollup devs to add pitching options for plugins to resolve conflicts like this. ... Probably should do that along with this issue, but I feel it would take ages to get implemented compared to simple filter in Vite transform plugins.

Additional context

No response

Validations

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[bluwy]

You could use Vite plugin's configResolved hook to access the list of plugins, including Vite's internal one, that patch the vite:json plugin too.

[brawaru]

Somehow missed the configResolved hook (perhaps because I tried config hook, which does not have built-in plugins) and used configureServer, but I suppose configResolve works better. Released a new version of my plugin that makes wrapping work in Vite too, but I still feel this issue is relevant, because having a way to exclude files from transformation without plugin patching is much better.