verify(mockLoadBalancer).selectChannel(mockOperation);
        verify(alternativeChannel).addPendingOperation(mockOperation);
    }

    @Test
    void testFailureWithNoAlternativeChannels() throws Exception {
        failedChannel.addPendingOperation(mockOperation);

        channelInfo.addPendingOperation(mockOperation);
        assertEquals(1, channelInfo.getRequestsPending());
        assertFalse(channelInfo.getPendingOperations().isEmpty());

        assertTrue(channelInfo.removePendingOperation(mockOperation));
        assertEquals(0, channelInfo.getRequestsPending());

        channelInfo.addPendingOperation(mockOperation);

    @Test
    void testLeastLoadedStrategy() {
        loadBalancer.setStrategy(LoadBalancingStrategy.LEAST_LOADED);

        // Add pending operations to channel1 to make it more loaded
        channel1.addPendingOperation(mockMessage);

        when(mockChannelManager.getHealthyChannels()).thenReturn(Arrays.asList(channel1, channel2));

        ChannelInfo selected = loadBalancer.selectChannel(mockMessage);