_config.js

export default {
	data: {
		x: 'initial'
	},

	html: `
		<p>x: initial</p>
		<button class="foo">foo</button>
		<p>foo x: initial</p>
		<button class="bar">bar</button>
		<p>bar x: initial</p>
		<button class="baz">baz</button>
		<p>baz x: initial</p>
	`,

	test ( assert, component, target, window ) {
		const click = new window.MouseEvent( 'click' );
		const buttons = [ ...target.querySelectorAll( 'button' ) ];

		buttons[0].dispatchEvent( click );

		assert.equal( component.get( 'x' ), 'p' );
		assert.htmlEqual( target.innerHTML, `
			<p>x: p</p>
			<button class="foo">foo</button>
			<p>foo x: p</p>
			<button class="bar">bar</button>
			<p>bar x: p</p>
			<button class="baz">baz</button>
			<p>baz x: p</p>
		` );

		buttons[1].dispatchEvent( click );

		assert.equal( component.get( 'x' ), 'q' );
		assert.htmlEqual( target.innerHTML, `
			<p>x: q</p>
			<button class="foo">foo</button>
			<p>foo x: q</p>
			<button class="bar">bar</button>
			<p>bar x: q</p>
			<button class="baz">baz</button>
			<p>baz x: q</p>
		` );

		buttons[2].dispatchEvent( click );

		assert.equal( component.get( 'x' ), 'r' );
		assert.htmlEqual( target.innerHTML, `
			<p>x: r</p>
			<button class="foo">foo</button>
			<p>foo x: r</p>
			<button class="bar">bar</button>
			<p>bar x: r</p>
			<button class="baz">baz</button>
			<p>baz x: r</p>
		` );
	}
};