@Test
public void channelPrimerShouldCallPoolConstruction() throws IOException {

  ChannelPrimer mockChannelPrimer = Mockito.mock(ChannelPrimer.class);
  ManagedChannel channel1 = Mockito.mock(ManagedChannel.class);
  ManagedChannel channel2 = Mockito.mock(ManagedChannel.class);
  ChannelPool.create(
      2, new FakeChannelFactory(Arrays.asList(channel1, channel2), mockChannelPrimer));
  Mockito.verify(mockChannelPrimer, Mockito.times(2))
      .primeChannel(Mockito.any(ManagedChannel.class));
}