add more tests for Timer (#2889)

superset/assets/spec/javascripts/sqllab/Timer_spec.jsx

@@ -1,6 +1,6 @@
 import React from 'react';
-import { shallow } from 'enzyme';
-import { describe, it } from 'mocha';
+import { mount } from 'enzyme';
+import { describe, it, beforeEach } from 'mocha';
 import { expect } from 'chai';
 
 import Timer from '../../../javascripts/components/Timer';
@@ -8,18 +8,44 @@ import { now } from '../../../javascripts/modules/dates';
 
 
 describe('Timer', () => {
+  let wrapper;
   const mockedProps = {
     startTime: now(),
     endTime: null,
     isRunning: true,
-    state: 'warning',
+    status: 'warning',
   };
-  it('is valid', () => {
-    expect(React.isValidElement(<Timer {...mockedProps} />))
-    .to.equal(true);
+
+  beforeEach(() => {
+    wrapper = mount(<Timer {...mockedProps} />);
   });
-  it('renders a span', () => {
-    const wrapper = shallow(<Timer {...mockedProps} />);
-    expect(wrapper.find('span')).to.have.length(1);
+
+  it('is a valid element', () => {
+    expect(React.isValidElement(<Timer {...mockedProps} />)).to.equal(true);
+  });
+
+  it('componentWillMount starts timer after 30ms and sets state.clockStr', () => {
+    expect(wrapper.state().clockStr).to.equal('');
+    setTimeout(() => {
+      expect(wrapper.state().clockStr).not.equal('');
+    }, 31);
+  });
+
+  it('calls startTimer on mount', () => {
+    const startTimerSpy = sinon.spy(Timer.prototype, 'startTimer');
+    wrapper.mount();
+    expect(Timer.prototype.startTimer.calledOnce);
+    startTimerSpy.restore();
+  });
+
+  it('calls stopTimer on unmount', () => {
+    const stopTimerSpy = sinon.spy(Timer.prototype, 'stopTimer');
+    wrapper.unmount();
+    expect(Timer.prototype.stopTimer.calledOnce);
+    stopTimerSpy.restore();
+  });
+
+  it('renders a span with the correct class', () => {
+    expect(wrapper.find('span').hasClass('label-warning')).to.equal(true);
   });
 });