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Bug: [no-unused-vars] Does not recognize usage in TS 4.7 "infer + extends" syntax #5330

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@pmer

Description

@pmer

Before You File a Bug Report Please Confirm You Have Done The Following...

  • I have tried restarting my IDE and the issue persists.
  • I have updated to the latest version of the packages.
  • I have searched for related issues and found none that matched my issue.
  • I have read the FAQ and my problem is not listed.

Playground Link

https://typescript-eslint.io/play/#ts=4.7.4&sourceType=module&code=C4TwDgpgBAGlC8UDOwBOBLAdgcygHykwFcBbAIwlQG4AoG0SKASQBMAeAFQD4EoOoIAD2ARMLJFADeUdCwBcMzADNKzFgOGjxsKAF8oAfjVQFmCADdKtGiwgBjADYBDVNCVFMd4OgD2mKEqcXAAU5k4ORBAKHAA0MvJqQQCUCuY+stZKwdKyCgCMenEATEm0QA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6Jge1tidmUQAmtAG4BDaKgwBtcNhyJo0DtEiyIAXVkBfEFqA&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA

Repro Code

type X = string | number;  // 'X' is defined but never used. 1:6 - 1:7

type Id<T> = T extends { id: infer Id extends X } ? Id : never;  // X is used here!

declare function f<T>(value: T, id: Id<T>): void;

f({ id: 1 }, 2);

ESLint Config

module.exports = {
  parser: "@typescript-eslint/parser",
  rules: {
    "@typescript-eslint/no-unused-vars": ["error"],
  },
};

tsconfig

{
}

Expected Result

I expected no error.

Actual Result

There was an error on line 1.

Additional Info

This is using the new infer + extends syntax from TypeScript 4.7.

Versions

package version
@typescript-eslint/eslint-plugin 5.30.5
@typescript-eslint/parser 5.30.5
TypeScript 4.7.4
ESLint 8.19.0
node 18.4.0

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    accepting prsGo ahead, send a pull request that resolves this issuebugSomething isn't workinggood first issueGood for newcomerspackage: scope-managerIssues related to @typescript-eslint/scope-manager

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