content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.cassandra.sidecar.client.selection;
  
  import java.util.Arrays;
  import java.util.Iterator;
  import java.util.List;
  import java.util.NoSuchElementException;
  
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  import org.apache.cassandra.sidecar.client.SidecarInstance;
  import org.apache.cassandra.sidecar.client.SidecarInstancesProvider;
  import org.apache.cassandra.sidecar.client.SimpleSidecarInstancesProvider;
  
  import static org.assertj.core.api.Assertions.assertThat;
  import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
  import static org.mockito.Mockito.mock;
  
  /**
   * Unit tests for the {@link OrderedInstanceSelectionPolicy}
   */
  class OrderedInstanceSelectionPolicyTest
  {
      List<SidecarInstance> mockInstanceList;
      SidecarInstance mockInstance1;
      SidecarInstance mockInstance2;
      SidecarInstance mockInstance3;
      SidecarInstance mockInstance4;
  
      @BeforeEach
      void setup()
      {
          mockInstance1 = mock(SidecarInstance.class);
          mockInstance2 = mock(SidecarInstance.class);
          mockInstance3 = mock(SidecarInstance.class);
          mockInstance4 = mock(SidecarInstance.class);
          mockInstanceList = Arrays.asList(mockInstance1, mockInstance2, mockInstance3, mockInstance4);
      }
  
      @Test
      public void testIterator()
      {
  
          SidecarInstancesProvider provider = new SimpleSidecarInstancesProvider(mockInstanceList);
          InstanceSelectionPolicy instanceSelectionPolicy = new OrderedInstanceSelectionPolicy(provider);
          Iterator<SidecarInstance> iterator = instanceSelectionPolicy.iterator();
  
          assertThat(iterator.hasNext()).isTrue().as("Expected to be true");
          assertThat(iterator.hasNext()).isTrue().as("Test idempotency of hasNext by running it again");
          assertThat(iterator.next()).isSameAs(mockInstance1);
          assertThat(iterator.hasNext()).isTrue();
          assertThat(iterator.next()).isSameAs(mockInstance2);
          assertThat(iterator.hasNext()).isTrue();
          assertThat(iterator.next()).isSameAs(mockInstance3);
          assertThat(iterator.hasNext()).isTrue();
          assertThat(iterator.next()).isSameAs(mockInstance4);
          assertThat(iterator.hasNext()).isFalse().as("Expected to be false");
          assertThat(iterator.hasNext()).isFalse().as("Test idempotency of hasNext by running it again");
          assertThatExceptionOfType(NoSuchElementException.class).isThrownBy(iterator::next);
      }
  }
  