`import/no-unresolved` if `tsconfig` from `references` is extended

[nikitayutanov]

The 4.x release was intended to rework tsconfig with specified references. Everything works as expected unless one of the referenced configs extends another config.

Reproduction

Here’s a repository with a quick reproduction of the issue. The main tsconfig.json references both tsconfig.app.json and tsconfig.node.json.

However, since tsconfig.app.json extends tsconfig.base.json, running the eslint CLI results in an import/no-unresolved error.

This issue persists unless multiple projects are explicitly specified in eslint.config.js.

Real-World Use Case

While this may seem redundant, a real-world scenario would involve tsconfig.app.json extending a config provided by an external package rather than a locally defined one. For example:

{
  "extends": "@tsconfig/recommended/tsconfig.json"
}

This is particularly useful because it is currently not possible to inherit a single main config when using references.

---

Is this the intended behavior? It seems there are differences in how extended tsconfig files are handled when specified in the main config references.

Feel free to let me know if you need further adjustments, and thanks for your efforts!

[JounQin]

cc @Boshen

[JounQin]

@nikitayutanov Would you like to try the latest version of eslint-import-resolver-typescript? I believe this should already been fixed at unrs/unrs-resolver#12.

[mauriceackel]

I think I'm facing the same issue and I'm using 4.4.2. In the PR you've linked @JounQin, I see that you take the references into account but does it also "expand" the references (i.e. expand the extends config) of those references tsconfig files?

Using this config, I get an unresolved error:

// tsconfig.json
{
  "files": [],
  "references": [
    { "path": "./tsconfig.ref.json" },
  ]
}

// tsconfig.ref.json
{
  "extends": "tsconfig.base.json",
  "include": [ "src" ]
}

However, when I add the baseUrl and paths to tsconfig.ref.json it works:

// tsconfig.json
{
  "files": [],
  "references": [
    { "path": "./tsconfig.ref.json" },
  ]
}

// tsconfig.ref.json
{
  "extends": "tsconfig.base.json",
  "compilerOptions": {
    "baseUrl": "${configDir}/src",
    "paths": { "@/*": [ "./*" ] }
  },
  "include": [ "src" ]
}

So to me it seems like the extends is not correctly expanded.

[mauriceackel]

After some digging, I think I have found the issue in unrs.

It seems like we extend the root config in the lib.rs file (here).

Afterwards, we load the references of the root config. However, when we load the referenced config files, we do not extend them anymore.

To fix this, I believe this code as to also be added here

[JounQin]

@mauriceackel Do you want to raise a PR instead?