Feature: Support ${configDir} template variable in tsconfig.json (added in typescript 5.5)

[chandu]

Description

As a developer using vite-plugin-dts I want to be able to use the ${configDir} template variable in tsconfig.json (added in typescript 5.5 - https://www.typescriptlang.org/docs/handbook/release-notes/typescript-5-5.html#the-configdir-template-variable-for-configuration-files ), specially when using a shared tsconfig in monorepo.

In it's current version, vite-plugin-dts is not generating any type defintiion files, when ${configDir} is used in the include property of tsconfig.json files.

The repo @ https://github.com/chandu/vite-dts-config-dir-test demonstrates the issue. Clone the repo and then issue the following commands:

pnpm i

pnpm run build // Prints Dts File Exists: true

pnpm run build-config-dir // Prints Dts File Exists: false, this script is running the build using the tsconfig that has the ${configDir} reference

Suggested solution

The issue happens to be because the newly introduced configDir template variable nuances are not used/leveared by the @vue/language-core package.

Where the configFileSpecs is assigned: https://github.com/microsoft/TypeScript/blob/main/src/compiler/commandLineParser.ts#L2945

Where the updated configFileSpecs is not leveraged: https://github.com/vuejs/language-tools/blob/7d44d8e844ef4f51407e57ce39e5570c9c9b6ece/packages/language-core/lib/utils/ts.ts#L84

Where the createParsedCommandLine function of @vue/language-core is called: https://github.com/qmhc/vite-plugin-dts/blob/main/src/plugin.ts#L261

I am not sure what is the right fix/solution.

One possible way is to modify the @vue/language-core to also return 'configFileSpecs' populated on the config object at https://github.com/vuejs/language-tools/blob/7d44d8e844ef4f51407e57ce39e5570c9c9b6ece/packages/language-core/lib/utils/ts.ts#L84 and the propagate that to the vite-plugin-dts where the include/exclude could be rightly used when calling the createFilter, ut would span updating more than one package.

or

use the tsconfig file/content to parse the file, get the configFileSpecs and use the validatedIncludeSpecs and validatedExcludeSpecs to create the filter at https://github.com/qmhc/vite-plugin-dts/blob/main/src/plugin.ts#L323

I am sure there could be better solutions, but this is what I could think of with limited insights into the typescript tsconfig parsing.

Alternative

For now, I am passing the resolved/hardcoded include/exlcude as the dts plugin options.

Additional context

No response

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