function testNine() {
  let callback = sinon.stub().returns(42);
  callback({ x: 5, y: 5 });
  callback.calledWithMatch({ x: 5 });
  callback.alwaysCalledWithMatch({ y: 5 });
  callback.neverCalledWithMatch({ x: 6 });
  callback.notCalledWithMatch({ x: 6 });
  sinon.assert.calledWithMatch(callback, { x: 5 });
  sinon.assert.alwaysCalledWithMatch(callback, { y: 5 });
  sinon.assert.neverCalledWithMatch(callback, { x: 6 });
}