1 files changed, 86 insertions, 0 deletions
diff --git a/preact/debug/test/browser/component-stack.test.js b/preact/debug/test/browser/component-stack.test.js
new file mode 100644
index 0000000..87cd085
--- /dev/null
+++ b/preact/debug/test/browser/component-stack.test.js
@@ -0,0 +1,86 @@
+import { createElement, render, Component } from 'preact';
+import 'preact/debug';
+import { setupScratch, teardown } from '../../../test/_util/helpers';
+
+/** @jsx createElement */
+
+describe('component stack', () => {
+	/** @type {HTMLDivElement} */
+	let scratch;
+
+	let errors = [];
+	let warnings = [];
+
+	const getStack = arr => arr[0].split('\n\n')[1];
+
+	beforeEach(() => {
+		scratch = setupScratch();
+
+		errors = [];
+		warnings = [];
+		sinon.stub(console, 'error').callsFake(e => errors.push(e));
+		sinon.stub(console, 'warn').callsFake(w => warnings.push(w));
+	});
+
+	afterEach(() => {
+		console.error.restore();
+		console.warn.restore();
+		teardown(scratch);
+	});
+
+	it('should print component stack', () => {
+		function Foo() {
+			return <Thrower />;
+		}
+
+		class Thrower extends Component {
+			constructor(props) {
+				super(props);
+				this.setState({ foo: 1 });
+			}
+
+			render() {
+				return <div>foo</div>;
+			}
+		}
+
+		render(<Foo />, scratch);
+
+		let lines = getStack(warnings).split('\n');
+		expect(lines[0].indexOf('Thrower') > -1).to.equal(true);
+		expect(lines[1].indexOf('Foo') > -1).to.equal(true);
+	});
+
+	it('should only print owners', () => {
+		function Foo(props) {
+			return <div>{props.children}</div>;
+		}
+
+		function Bar() {
+			return (
+				<Foo>
+					<Thrower />
+				</Foo>
+			);
+		}
+
+		class Thrower extends Component {
+			render() {
+				return (
+					<table>
+						<td>
+							<tr>foo</tr>
+						</td>
+					</table>
+				);
+			}
+		}
+
+		render(<Bar />, scratch);
+
+		let lines = getStack(errors).split('\n');
+		expect(lines[0].indexOf('td') > -1).to.equal(true);
+		expect(lines[1].indexOf('Thrower') > -1).to.equal(true);
+		expect(lines[2].indexOf('Bar') > -1).to.equal(true);
+	});
+});