Skip to content

Bug: [no-unnecessary-condition] don't flag values of an unconstrained or valid type parameter #10442

@ronami

Description

@ronami

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=5.7.2&fileType=.tsx&code=CYUwxgNghgTiAEYD2A7AzgF3hkmCMAXPABQCU8AvAHzwBGSSEIUKA3AFCiSwLLpY5MAJiJlKNAK4oA1iiQB3Np3DQ4iVJmy4MAZiIAeACpUx1eIY5dVvDQO0AWA4fggAHjhTA0dBkxYnyMwt2dgB6UPgAByg0NFx2AG08ABp4FAkICABdADoAMwBLCBwYYkEMPFIOMIjo2Pik1PTM3MLikFLyoSqQ8Pg0AAskDOAomLRElLSM7PyikrLtHR6a-qGRsdjJppnW%2BY7FzHseoA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6Jge1tiacTJTIAhtEK0yHJgBNK%2BSpPRRE0aB2iRwYAL4gtQA&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA&tokens=false

Repro Code

declare const test1: () => boolean;
declare const test2: () => unknown;
declare const test3: <T>() => T;
declare const test4: <T extends boolean>() => T;

// passes
[1, null].filter(test1);

// passes
[1, null].filter(test2);

// should pass
[1, null].filter(test3);

// should pass
[1, null].filter(test4);

ESLint Config

module.exports = {
  parser: "@typescript-eslint/parser",
  rules: {
    "@typescript-eslint/no-unnecessary-condition": "error"
  },
};

tsconfig

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

Expected Result

I expect all use-cases to be consistent and not report as errors.

Actual Result

The use-cases with a type constraint report (unnecessarily) as an error.

Additional Info

This seems similar to #10311 and looks like the fix should be similar.

Metadata

Metadata

Assignees

No one assigned

    Labels

    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

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions

      pFad - Phonifier reborn

      Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.

      Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.


      Alternative Proxies:

      Alternative Proxy

      pFad Proxy

      pFad v3 Proxy

      pFad v4 Proxy