[Bug]: dts not generated in monorepo

[yf-yang]

Version

System:
    OS: macOS 13.2.1
    CPU: (16) x64 Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
    Memory: 145.51 MB / 32.00 GB
    Shell: 5.8.1 - /bin/zsh
  Browsers:
    Chrome: 133.0.6943.98
    Safari: 16.3
  npmPackages:
    @rslib/core: ^0.5.0 => 0.5.0

Details

Based on my observation, that's an issue with tsconfig dependency

There is a monorepo containing two folders tsconfig and pkg. tsconfig is a pure json package (@my/ts-config), it exposes base.json. The root of the monorepo adds @my/ts-config as a dependency.

pkg does not declare @my/ts-config as dependency and pkg/tsconfig.json depends on @my/ts-config/base. tsserver can resolve to the base.json correctly, but rslib can't and dts is not generated.

When copying all the contents from tsconfig/base.json directly to pkg/tsconfig.json, rslib is able to generate the dts files.

Reproduce link

https://github.com/yf-yang/rslib-monorepo-dts-bug

Reproduce Steps

pnpm i
cd pkg
pnpm build

dist/ does not contain dts file

[Timeless0911]

You can run npx tsc in pkg, which generated dts in tsconfig/dist as same as Rslib did.

You should set "declarationDir": "dist" in pkg/tsconfig.json though.

[yf-yang]

@Timeless0911 I am not sure about declarationDir part. Does tsconfig's reference say it is not inherited? I did receive the error from rslib and added it to the root config

[Timeless0911]

I think the error message is correct

[yf-yang]

OK, seems "declarationDir" is resolved relative to the config that defines it.

[yf-yang]

@Timeless0911 Could you consider triggering a warning if the dts are found in a different folder than their associated js? I'm not entirely sure about the complexity this might entail for various scenarios, just an idea

[Timeless0911]

Good idea, I think a warning can be give when declarationDir or outDir is outside the project root.