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.kafka.common.security;
  
  import org.apache.kafka.common.security.auth.SaslExtensions;
  
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  
  import static org.junit.jupiter.api.Assertions.assertNotEquals;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class SaslExtensionsTest {
      Map<String, String> map;
  
      @BeforeEach
      public void setUp() {
          this.map = new HashMap<>();
          this.map.put("what", "42");
          this.map.put("who", "me");
      }
  
      @Test
      public void testReturnedMapIsImmutable() {
          SaslExtensions extensions = new SaslExtensions(this.map);
          assertThrows(UnsupportedOperationException.class, () -> extensions.map().put("hello", "test"));
      }
  
      @Test
      public void testCannotAddValueToMapReferenceAndGetFromExtensions() {
          SaslExtensions extensions = new SaslExtensions(this.map);
  
          assertNull(extensions.map().get("hello"));
          this.map.put("hello", "42");
          assertNull(extensions.map().get("hello"));
      }
  
      /**
       * Tests that even when using the same underlying values in the map, two {@link SaslExtensions}
       * are considered unique.
       *
       * @see SaslExtensions class-level documentation
       */
      @Test
      public void testExtensionsWithEqualValuesAreUnique() {
          // If the maps are distinct objects but have the same underlying values, the SaslExtension
          // objects should still be unique.
          assertNotEquals(new SaslExtensions(Collections.singletonMap("key", "value")),
              new SaslExtensions(Collections.singletonMap("key", "value")),
              "SaslExtensions with unique maps should be unique");
  
          // If the maps are the same object (with the same underlying values), the SaslExtension
          // objects should still be unique.
          assertNotEquals(new SaslExtensions(map),
              new SaslExtensions(map),
              "SaslExtensions with duplicate maps should be unique");
  
          // If the maps are empty, the SaslExtension objects should still be unique.
          assertNotEquals(SaslExtensions.empty(),
              SaslExtensions.empty(),
              "SaslExtensions returned from SaslExtensions.empty() should be unique");
      }
  }
  