Adjust types to allow initialFocus: () => undefined

[FloEdelmann]

initialFocus can be undefined, in this case the first tabbable node will be focused. Also, we can pass a function returning an element. But we can't return undefined in that function (according to the types):

focus-trap/index.d.ts

Line 12 in 94645eb

export type FocusTarget = FocusTargetValue | (() => FocusTargetValue);

But according to the implementation, it actually works:

focus-trap/index.js

Line 270 in 94645eb

let node = getNodeForOption('initialFocus');

focus-trap/index.js

Lines 233 to 267 in 94645eb

	const getNodeForOption = function (optionName, ...params) {
	let optionValue = config[optionName];
	if (typeof optionValue === 'function') {
	optionValue = optionValue(...params);
	}
	if (optionValue === true) {
	optionValue = undefined; // use default value
	}
	if (!optionValue) {
	if (optionValue === undefined || optionValue === false) {
	return optionValue;
	}
	// else, empty string (invalid), null (invalid), 0 (invalid)
	throw new Error(
	`\`${optionName}\` was specified but was not a node, or did not return a node`
	);
	}
	let node = optionValue; // could be HTMLElement, SVGElement, or non-empty string at this point
	if (typeof optionValue === 'string') {
	node = doc.querySelector(optionValue); // resolve to node, or null if fails
	if (!node) {
	throw new Error(
	`\`${optionName}\` as selector refers to no known node`
	);
	}
	}
	return node;
	};

So I suggest to adjust the types to allow undefined as a valid function return type.

[stefcameron]

@FloEdelmann You're correct! Setting the option to undefined or a function that returns undefined is specifically handled in getInitialFocusNode() so the docs and typings should reflect that. Thank you for bringing this to my attention.

I'll get this sorted shortly!

[stefcameron]

@FloEdelmann Please have a look at #1062 and LMK if the typings look good now.

[stefcameron]

Fix published in v7.5.3

[FloEdelmann]

Thanks!