@webcomponents/custom-elements
Version:
HTML Custom Elements Polyfill
119 lines (88 loc) • 3.37 kB
HTML
<html>
<head>
<title>Element#setAttribute</title>
<script>
(window.customElements = window.customElements || {}).forcePolyfill = true;
</script>
<script src="../../../../es6-promise/dist/es6-promise.auto.min.js"></script>
<script src="../../../../web-component-tester/browser.js"></script>
<script src="../../../custom-elements.min.js"></script>
</head>
<body>
<script>
function generateLocalName() {
return 'test-element-' + Math.random().toString(32).substring(2);
}
function defineWithLocalName(localName, observedAttributes) {
customElements.define(localName, class extends HTMLElement {
static get observedAttributes() { return observedAttributes; }
constructor() {
super();
this.constructed = true;
this.connectedCallbackCount = 0;
this.disconnectedCallbackCount = 0;
this.attrCallbackArgs = [];
}
connectedCallback() {
this.connectedCallbackCount++;
}
disconnectedCallback() {
this.disconnectedCallbackCount++;
}
attributeChangedCallback(name, oldValue, newValue, namespace) {
this.attrCallbackArgs.push(Array.prototype.slice.apply(arguments));
}
});
}
suite('Setting new values.', function() {
let localName1;
setup(function() {
localName1 = generateLocalName();
defineWithLocalName(localName1, []);
localName2 = generateLocalName();
defineWithLocalName(localName2, ['attr']);
});
test('Changes to unobserved attributes do not trigger callbacks.', function() {
const element = document.createElement(localName1);
assert.equal(element.attrCallbackArgs.length, 0);
element.setAttribute('attr', 'abc');
assert.equal(element.attrCallbackArgs.length, 0);
});
test('Changes to observed attributes trigger callbacks.', function() {
const element = document.createElement(localName2);
assert.equal(element.attrCallbackArgs.length, 0);
element.setAttribute('attr', 'abc');
assert.equal(element.attrCallbackArgs.length, 1);
assert.deepEqual(element.attrCallbackArgs[0], ['attr', null, 'abc', null]);
});
});
suite('Changing previously set values.', function() {
let localName;
setup(function() {
localName = generateLocalName();
defineWithLocalName(localName, ['attr']);
});
test('Setting an observed attribute to its current value does trigger a callback.', function() {
const element = document.createElement(localName);
assert.equal(element.attrCallbackArgs.length, 0);
element.setAttribute('attr', 'abc');
assert.equal(element.attrCallbackArgs.length, 1);
assert.deepEqual(element.attrCallbackArgs[0], ['attr', null, 'abc', null]);
element.setAttribute('attr', 'abc');
assert.equal(element.attrCallbackArgs.length, 2);
});
test('Setting an observed attribute to a different value triggers a callback.', function() {
const element = document.createElement(localName);
assert.equal(element.attrCallbackArgs.length, 0);
element.setAttribute('attr', 'abc');
assert.equal(element.attrCallbackArgs.length, 1);
assert.deepEqual(element.attrCallbackArgs[0], ['attr', null, 'abc', null]);
element.setAttribute('attr', 'def');
assert.equal(element.attrCallbackArgs.length, 2);
assert.deepEqual(element.attrCallbackArgs[1], ['attr', 'abc', 'def', null]);
});
});
</script>
</body>
</html>