• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

{
  "rules": {
    "@typescript-eslint/no-unnecessary-type-constraint": "error"
  }
}

Consider the following example:

const maybe = <T extends any>(whatever: T): T => {
  console.log(Object.keys(whatever)) // TS is complaining, which is good
  return whatever
}

It's dummy but it has a problem: calling maybe(null) will throw a runtime error (TypeError: Cannot convert undefined or null to object). Therefore I'd like Typescript to fail here. It does now, all good so far.

The rule no-unnecessary-type-constraint suggests replacing <T extends any> with <T>, because "Constraining the generic type `T` to `any` does nothing and is unnecessary."

So I change it to:

const maybe = <T>(whatever: T): T => {
  console.log(Object.keys(whatever)))
  return whatever
}

Result: TS is silent, the code is not safe against a runtime error.

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