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Bug: [@typescript-eslint/no-unnecessary-type-assertion] False positives for "as const" assertions #8721

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@ashvinsrivatsa

Description

@ashvinsrivatsa

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=5.4.2&fileType=.tsx&code=KYDwDg9gTgLgBAYwgOwM7wLYEMoGthRwC8cARNngaXFqoiugNwCwAUKJLHAJbIwEAzLAmBwAIlhhY4AbzZw4FfFABccGAE8wwCAMU5lLVgoBuWADYBXYGvRReAcyMBfNgMvIEMbikRRgksASUgAUAJRqwdJyxvRo8ABGtKIkMvqUqunKcM5GCv4wllDIsnAAdBVJqMAANHBmVjZk1LlszkA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6Jge1tiacTJTIAhtEK0ipWkOTJE0fJQ5N0UOdA7RI4MAF8QOoA&tsconfig=N4KAvkA&tokens=false

Repro Code

export const marker = "marker" as const;
export interface Data {
  marker: typeof marker;
  value: string;
}
function createData(): Data {
  const base = { marker: marker };
  return { ...base, value: "" };
}

ESLint Config

module.exports = {
  "rules": {
    "@typescript-eslint/no-unnecessary-type-assertion": "error"
  }
}

tsconfig

{
}

Expected Result

The first line of this code should not report an error for the as const assertion, since this assertion is necessary - removing it is a TypeScript compilation error (see TypeScript playground).

Actual Result

Starting in typescript-eslint@7.3 (presumably #8558), the first line of this code reports a @typescript-eslint/no-unnecessary-type-assertion error.

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    accepting prsGo ahead, send a pull request that resolves this issuebugSomething isn't workinglocked due to agePlease open a new issue if you'd like to say more. See https://typescript-eslint.io/contributing.package: eslint-pluginIssues related to @typescript-eslint/eslint-plugin

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