TS2322: Type 'null' is not assignable to type 'void | Diff'

[jantimon]

the diff function return type is Diff | void however it returns null in line 152:

json-delta/index.ts

Lines 144 to 154 in 41275a6

	export function diff(
	a: AnyJson,
	b: AnyJson,
	tolerance = Infinity
	): Diff | void {
	let result: Diff = [];
	if (gatherDiff(a, b, tolerance, [], result) || result.length > tolerance)
	return [[[], b]];
	if (result.length === 0) return null;
	return result;
	}

I can prepare a PR if it helps