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Bug: [prefer-for-of] false positive when using non-null assertion within update expressions #10977

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@zyoshoka

Description

@zyoshoka

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=5.8.2&fileType=.tsx&code=MYewdgzgLgBAhgJwXAnjAvDA2gRgDQwDMhBATACwEC0AnALoDcAUEwPSswgDWTAZiAhgAKADYBTWAEsMMAAwMY0gDzwkqAHTiwAcygALBZIDURgJSrkKLJLonmbDrziSRfAcPFSZ8xTBWJLTTEdfUMTcwDUazoAQjsmIA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6Y6RAM0Wlq4D2fAV3RRe0IZHBgAviFlA&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA&tokens=false

Repro Code

const array = [1, 33, 24, -9];

// ok
for (let i = 0; i < array.length; i++) array[i]++;

// fail
for (let i = 0; i < array.length; i++) array[i]!++;

ESLint Config

module.exports = {
  parser: "@typescript-eslint/parser",
  rules: {
    "@typescript-eslint/prefer-for-of": "error",
  },
};

tsconfig

{
  "compilerOptions": {
    "strictNullChecks": true
  }
}

Expected Result

The 7th line shouldn't report prefer-for-of error.

Actual Result

The 7th line reports prefer-for-of error.

Additional Info

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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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