Support customConditions in tsconfig.json

[colinhacks]

Acknowledgements

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Minimal reproduction URL

This is actually a feature request sorry :(

It would be cool if tsx automatically read customConditions from tsconfig.json and passed it to node using --conditions.

Problem & expected behavior (under 200 words)

"Repro" is https://github.com/colinhacks/live-typescript-monorepo

gh repo clone https://github.com/colinhacks/live-typescript-monorepo
cd live-typescript-monorepo/custom-conditions
pnpm i
cd packages/pkg-b
tsx index.ts # module resolution error
tsx --conditions source index.ts # works!

I'm using custom export conditions in my TypeScript monorepo (described in more detail here). Since tsconfig.json already supports the customConditions compiler option for specifying custom export conditions, it would be cool if tsx could read that and incorporate it into module resolution automatically.

Bugs are expected to be fixed by those affected by it

• I'm interested in working on this issue

Compensating engineering work financially will speed up resolution

• I'm willing to offer financial support

[privatenumber]

Feature requests are reserved for sponsors, but I'll accept this for you @colinhacks!

This should be trivial to support for ESM, but it may be challenging with the CJS resolver as it doesn't seem to offer a way to accept conditions:
https://github.com/nodejs/node/blob/main/lib/internal/modules/cjs/loader.js#L1126

[privatenumber]

Looks like Node added customConditions in the CommonJS loader: https://github.com/nodejs/node/pull/55698/files#diff-5b5902273122e094ff474fda358605ffa45a4a58b51cd0bf4c1acb93779df142R1326

This may be feasible to implement in tsx now.