💅 `noUnusedPrivateClassMembers` does not handle bracket notation

[mrazauskas]

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Workspace:
  Open Documents:               0

Rule name

noUnusedPrivateClassMembers

Playground link

https://biomejs.dev/playground/?lintRules=noUnusedPrivateClassMembers&code=ZQB4AHAAbwByAHQAIABjAGwAYQBzAHMAIABTAGEAbQBwAGwAZQAgAHsACgAgACAAcAByAGkAdgBhAHQAZQAgAGEAZABkADsACgAgACAAcAByAGkAdgBhAHQAZQAgAHIAZQBtAG8AdgBlADsACgAKACAAIABjAG8AbgBzAHQAcgB1AGMAdABvAHIAKAApACAAewAKACAAIAAgACAAdABoAGkAcwAuAGEAZABkACAAPQAgACgAKQAgAD0APgAgAHsAfQAKACAAIAAgACAAdABoAGkAcwAuAHIAZQBtAG8AdgBlACAAPQAgACgAKQAgAD0APgAgAHsAfQAKACAAIAB9AAoACgAgACAAbwBuACgAYQBjAHQAaQBvAG4AOgAgACIAYQBkAGQAIgAgAHwAIAAiAHIAZQBtAG8AdgBlACIAKQAgAHsACgAgACAAIAAgAHQAaABpAHMAWwBhAGMAdABpAG8AbgBdACgAKQAKACAAIAB9AAoAfQA%3D

Expected result

In one project I have logic similar to the following:

export class Sample {
  private add;
  private remove;

  constructor() {
    this.add = () => {}
    this.remove = () => {}
  }

  on(action: "add" | "remove") {
    this[action]()
  }
}

Because of type information, TypeScript’s noUnusedLocals is able to understand that both this.add and this.remove are not unused. At the moment noUnusedPrivateClassMembers reports them as unused, but that is not correct.

Not sure if that is possible to fix. What you think?

Code of Conduct

• I agree to follow Biome's Code of Conduct

[Conaclos]

To avoid false positive and complex machinery, we could just consider that a computed access can access any member. Hence, in such classes we could just consider that all members are used.

If we choose to implement this, we should document it in a caveat section in the rule docs.

[mrazauskas]

we could just consider that a computed access can access any member

This will work perfectly with my project. Thanks for taking the time to find the solution!