Option to specify `outExtension` for generated dts files?

[errmayank]

Like we can modify output extension of JavaScript files is there also a way to do the same for type definition files?

I tried returning this because dts was showing up in the autocomplete return options but it doesn't work.

format: ['cjs', 'esm'],
outExtension({ format }) {
  switch (format) {
    case 'cjs': {
      return { js: '.cjs', dts: '.d.cts' };
    }
    case 'esm': {
      return { js: '.mjs', dts: '.d.mts' };
    }
    default: {
      return { js: '.js', dts: '.d.ts' };
    }
  }
}

Output type definition files generated after building have extensions .d.ts and .d.cts which is the default since my package is of type module. Is there a way to do this?

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[rodrigoehlers]

Facing the exact same problem.

[egorderg]

It looks like 'outExtension' is overridden to 'undefined' when it's passed to rollup. In the rollup dts handling is even a check if there is a custom 'outExtension'.

[Lonli-Lokli]

is there any workaround? I would like to use 'file.d.mts' for esm typings.

There is no merged PR but seems like nobody want to merge it

[Lonli-Lokli]

@zvictor Seems like dts factory has been disabled explicitly? https://github.com/egoist/tsup/pull/668

Is there any way to specify it, eg use https://github.com/vkiryukhin/jsonfn?

Or merge https://github.com/egoist/tsup/pull/1053/files ?