/**
 * Create a unique session id.
 */
function createSessionModel(id = ''): Session.IModel {
  return {
    id: id || uuid(),
    notebook: { path: uuid() },
    kernel: { id: uuid(), name: uuid() }
  };
}

    it('should not be emitted for an iopub signal', async () => {
      const kernel = await tester.start();

      // We'll send two messages, first an iopub message, then a shell message.
      // The unhandledMessage signal should only emit once for the shell message.
      const msgId = uuid();
      const emission = testEmission(kernel.unhandledMessage, {
        test: (k, msg) => { expect(msg.header.msg_id).to.be(msgId); }
      });

      // Send an iopub message.
      tester.sendStatus(uuid(), 'idle');

      // Send a shell message.
      let msg = KernelMessage.createShellMessage({
        msgType: 'foo',
        channel: 'shell',
        session: tester.serverSessionId,
        msgId
      });
      msg.parent_header = {session: kernel.clientId};
      tester.send(msg);

      await emission;
    });

 it('should generate a random 32 character hex string', () => {
   let id0 = uuid();
   let id1 = uuid();
   expect(id0.length).to.equal(32);
   expect(id1.length).to.equal(32);
   expect(id0).to.not.equal(id1);
 });

/**
 * Create a unique session id.
 */
function createSessionModel(id = ''): Session.IModel {
  return {
    id: id || uuid(),
    path: uuid(),
    type: '',
    name: '',
    kernel: { id: uuid(), name: uuid() }
  };
}

 beforeEach((done) => {
   tester = new KernelTester();
   data = [{ id: uuid(), name: 'test' },
           { id: uuid(), name: 'test2' }];
   tester.runningKernels = data;
   manager = new KernelManager();
   expect(manager.specs).to.be(null);
   expect(manager.running().next()).to.be(void 0);
   manager.ready.then(done, done);
 });

 it('should yield a list of valid kernel ids', (done) => {
   let data = [
     { id: uuid(), name: 'test' },
     { id: uuid(), name: 'test2' }
   ];
   tester.runningKernels = data;
   Kernel.listRunning().then(response => {
     let running = toArray(response);
     expect(running[0]).to.eql(data[0]);
     expect(running[1]).to.eql(data[1]);
     done();
   });
 });

function createFactory() {
  return new WidgetFactory({
    name: uuid(),
    fileExtensions: ['.txt', '.foo.bar'],
    defaultFor: ['.txt', '.foo.bar']
  });
}