In node-red-node-test-helper input handler not called on errors and warnings

[ttoktassynov]

Beware that if you are testing an error or warning condition of your node behavior then currently input handler doesn't get called while unit testing.

So assuming this code:

// somewhere in FooNode constructor
this.on('input', msg => {
  if (msg.omg) {
    this.error('lolwtf');
  }
  // ..etc..
});

This wouldn't work:

describe('if `omg` in input message', function () {
  it('should call `error` with "lolwtf" ', function (done) {
    const flow = {
      name: 'n1',
      /* ..etc.. */
    };
    helper.load(FooNode, flow, function () {
      const n1 = helper.getNode('n1')
      n1.receive({omg: true});
      n1.on('input', () => {
        n1.warn.should.be.calledWithExactly('lolwtf');
        done();
      });
    });
  });
});

It would just result in timeout.
Here is reported issue