date-picker/test/unit/show.spec.js

A simple client-side date-picker

describe('unit/show.spec.js', function() {
	var ctor = require('../helpers/date-picker')
	  , dp

	beforeEach(function() {
		dp = new ctor();
	});

	describe('When calling show()', function() {
		var showSpy
		  , showResult

		describe('with valid parameters', function() {
			beforeEach(function() {
				var elm = document.createElement('div')

				// We don't care about rendering. We will just make this a noop
				dp.render = function() { return document.createElement('div'); };

				showSpy = sinon.spy();
				dp.on('show', showSpy);

				showResult = dp.show(elm);
			});

			it('should emit a "show" event', function() {
				expect(showSpy).to.have.been.called;
			});
			it('should pass the date-picker to the event-listener', function() {
				expect(showSpy).to.have.been.calledWith(dp);
			});

			it('should return the date-picker, for chaining', function() {
				expect(showResult).to.equal(dp);
			});
		});

		describe('with an invalid selector', function() {
			beforeEach(function() {
				sinon.stub(document, 'querySelector').returns(null);
			});
			afterEach(function() {
				document.querySelector.restore();
			});
			it('should attempt to look it up', function() {
				expect(function() {
					dp.show('invalid');
				}).to['throw']();

				expect(document.querySelector).to.have.been.calledWith('invalid');
			});
			it('should throw an exception', function() {
				expect(function() {
					dp.show('invalid');
				}).to['throw']('"invalid" does not resolve to an element!');
			});
		});
	});
});