Files
openlayers/test/spec/ol/observable.test.js
2018-07-26 10:14:58 -06:00

149 lines
3.8 KiB
JavaScript

import EventTarget from '../../../src/ol/events/Target.js';
import Observable, {unByKey} from '../../../src/ol/Observable.js';
describe('ol.Observable', function() {
describe('constructor', function() {
it('creates a new observable', function() {
const observable = new Observable();
expect(observable).to.be.a(Observable);
expect(observable).to.be.a(EventTarget);
});
});
describe('#on()', function() {
let observable, listener;
beforeEach(function() {
observable = new Observable();
listener = sinon.spy();
});
it('registers a listener for events of the given type', function() {
observable.on('foo', listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
observable.dispatchEvent('foo');
expect(listener.callCount).to.be(2);
});
it('accepts an array of event types', function() {
observable.on(['foo', 'bar'], listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
observable.dispatchEvent('bar');
expect(listener.callCount).to.be(2);
});
it('returns a listener key', function() {
const key = observable.on('foo', listener);
expect(typeof key).to.be('object');
});
});
describe('#once()', function() {
let observable, listener;
beforeEach(function() {
observable = new Observable();
listener = sinon.spy();
});
it('registers a listener that is only called once', function() {
observable.once('foo', listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
observable.dispatchEvent('foo');
expect(listener.callCount).to.be(1);
});
it('is safe to dispatch events of same type in a once listener', function() {
let callCount = 0;
observable.once('change', function() {
observable.changed();
observable.changed();
});
observable.on('change', function() {
++callCount;
});
expect(function() {
observable.changed();
}).to.not.throwException();
expect(callCount).to.be(3);
});
it('accepts an array of event types (called once for each)', function() {
observable.once(['foo', 'bar'], listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
observable.dispatchEvent('foo');
expect(listener.callCount).to.be(1);
observable.dispatchEvent('bar');
expect(listener.callCount).to.be(2);
observable.dispatchEvent('bar');
expect(listener.callCount).to.be(2);
});
it('returns a listener key', function() {
const key = observable.once('foo', listener);
expect(typeof key).to.be('object');
});
});
describe('#un()', function() {
let observable, listener;
beforeEach(function() {
observable = new Observable();
listener = sinon.spy();
});
it('unregisters a previously registered listener', function() {
observable.on('foo', listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
observable.un('foo', listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
});
});
describe('ol.Observable.unByKey()', function() {
let observable, listener;
beforeEach(function() {
observable = new Observable();
listener = sinon.spy();
});
it('unregisters a listener given the key returned by `on`', function() {
const key = observable.on('foo', listener);
observable.dispatchEvent('foo');
expect(listener.calledOnce).to.be(true);
unByKey(key);
observable.dispatchEvent('foo');
expect(listener.callCount).to.be(1);
});
});
});