Incorrect types for focusManager.setEventListener

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Describe the bug

The method focusManager.setEventListener accepts a SetupFn as parameter. And a setupFn is a function with a parameter setFocused: (focused?: boolean) => void.

The docs provide the following example:

focusManager.setEventListener((handleFocus) => {
  // Listen to visibilitychange
  if (typeof window !== 'undefined' && window.addEventListener) {
    window.addEventListener('visibilitychange', handleFocus, false)
    return () => {
      // Be sure to unsubscribe if a new handler is set
      window.removeEventListener('visibilitychange', handleFocus)
    }
  }
})

While this code works (!), it is not valid in TypeScript, because handleFocus is actually setFocused: (focused?: boolean) => void which is not valid as event listener callback function.

Note: This is also an issue, when not explicitly typing handleFocus (as in the docs example).

Your minimal, reproducible example

here

Steps to reproduce

Check the call of window.addEventListener("visibilitychange", setFocused, false); towards TypeScript errors.

Expected behavior

The given example should be valid TypeScript.

How often does this bug happen?

Every time

Screenshots or Videos

Platform

• OS: macOS
• Browser: Firefox, Chrome

Tanstack Query adapter

None

TanStack Query version

5.8.4

TypeScript version

6.9.1

Additional context

No response

[TkDodo]

seems just like a docs issue? The actual code we use is:

query/packages/query-core/src/focusManager.ts

Lines 16 to 30 in 1d3ee67

	this.#setup = (onFocus) => {
	// addEventListener does not exist in React Native, but window does
	// eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
	if (!isServer && window.addEventListener) {
	const listener = () => onFocus()
	// Listen to visibilitychange
	window.addEventListener('visibilitychange', listener, false)
	return () => {
	// Be sure to unsubscribe if a new handler is set
	window.removeEventListener('visibilitychange', listener)
	}
	}
	return
	}

so this indirection is all that's missing:

const listener = () => setFocused()

want to PR a docs change?

[BreakBB]

want to PR a docs change?

Sure!