svelte/test/runtime/samples/component-slot-let-inline-function/_config.js

let logs;
function log(value) {
	logs.push(value);
}

export default {
	html: '<button>click me</button>',
	props: {
		a: 'a',
		b: 'b',
		log
	},
	before_test() {
		logs = [];
	},
	async test({ assert, component, target, window }) {
		const button = target.querySelector('button');
		await button.dispatchEvent(new window.MouseEvent('click'));

		assert.deepEqual(logs, ['a: a, b: b']);

		component.a = '1'; 
		component.b = '2';
		await button.dispatchEvent(new window.MouseEvent('click'));
		assert.deepEqual(logs, ['a: a, b: b', 'a: 1, b: 2']);
	}
};