guava-tests/test/com/google/common/reflect/MutableTypeToInstanceMapTest.java

/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed 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 com.google.common.reflect;

import static org.truth0.Truth.ASSERT;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.testing.MapTestSuiteBuilder;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;
import com.google.common.collect.testing.testers.MapPutTester;
import com.google.common.reflect.ImmutableTypeToInstanceMapTest.TestTypeToInstanceMapGenerator;

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

import java.lang.reflect.Method;
import java.util.Map;
import java.util.Map.Entry;

/**
 * Unit test of {@link MutableTypeToInstanceMap}.
 *
 * @author Ben Yu
 */
public class MutableTypeToInstanceMapTest extends TestCase {

  public static Test suite() {
    TestSuite suite = new TestSuite();
    suite.addTestSuite(MutableTypeToInstanceMapTest.class);

    // Suppress this one because the tester framework doesn't understand that
    // *some* remappings will be allowed and others not.
    Method remapTest = null;
    try {
      remapTest = MapPutTester.class.getMethod(
          "testPut_replaceNullValueWithNonNullSupported");
    } catch (NoSuchMethodException e) {
      throw new AssertionError();
    }

    suite.addTest(MapTestSuiteBuilder
        .using(new TestTypeToInstanceMapGenerator() {
          // Other tests will verify what real, warning-free usage looks like
          // but here we have to do some serious fudging
          @Override
          @SuppressWarnings("unchecked")
          public Map<TypeToken, Object> create(Object... elements) {
            MutableTypeToInstanceMap<Object> map
                = new MutableTypeToInstanceMap<Object>();
            for (Object object : elements) {
              Entry<TypeToken, Object> entry = (Entry<TypeToken, Object>) object;
              map.putInstance(entry.getKey(), entry.getValue());
            }
            return (Map) map;
          }
        })
        .named("MutableTypeToInstanceMap")
        .withFeatures(
            MapFeature.SUPPORTS_REMOVE,
            MapFeature.RESTRICTS_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            CollectionFeature.SUPPORTS_ITERATOR_REMOVE,
            CollectionSize.ANY,
            MapFeature.ALLOWS_ANY_NULL_QUERIES)
        .suppressing(remapTest)
        .createTestSuite());

    return suite;
  }

  private TypeToInstanceMap<Object> map;

  @Override protected void setUp() throws Exception {
    map = new MutableTypeToInstanceMap<Object>();
  }

  public void testPutThrows() {
    try {
      map.put(TypeToken.of(Integer.class), new Integer(5));
      fail();
    } catch (UnsupportedOperationException expected) {}
  }

  public void testPutAllThrows() {
    try {
      map.putAll(ImmutableMap.of(TypeToken.of(Integer.class), new Integer(5)));
      fail();
    } catch (UnsupportedOperationException expected) {}
  }

  public void testEntrySetMutationThrows() {
    map.putInstance(String.class, "test");
    assertEquals(TypeToken.of(String.class), map.entrySet().iterator().next().getKey());
    assertEquals("test", map.entrySet().iterator().next().getValue());
    try {
      map.entrySet().iterator().next().setValue(1);
      fail();
    } catch (UnsupportedOperationException expected) {}
  }

  public void testEntrySetToArrayMutationThrows() {
    map.putInstance(String.class, "test");
    @SuppressWarnings("unchecked") // Should get a CCE later if cast is wrong
    Entry<Object, Object> entry = (Entry<Object, Object>) map.entrySet().toArray()[0];
    assertEquals(TypeToken.of(String.class), entry.getKey());
    assertEquals("test", entry.getValue());
    try {
      entry.setValue(1);
      fail();
    } catch (UnsupportedOperationException expected) {}
  }

  public void testEntrySetToTypedArrayMutationThrows() {
    map.putInstance(String.class, "test");
    @SuppressWarnings("unchecked") // Should get a CCE later if cast is wrong
    Entry<Object, Object> entry = map.entrySet().toArray(new Entry[0])[0];
    assertEquals(TypeToken.of(String.class), entry.getKey());
    assertEquals("test", entry.getValue());
    try {
      entry.setValue(1);
      fail();
    } catch (UnsupportedOperationException expected) {}
  }

  public void testPutAndGetInstance() {
    assertNull(map.putInstance(Integer.class, new Integer(5)));

    Integer oldValue = map.putInstance(Integer.class, new Integer(7));
    assertEquals(5, (int) oldValue);

    Integer newValue = map.getInstance(Integer.class);
    assertEquals(7, (int) newValue);
    assertEquals(7, (int) map.getInstance(TypeToken.of(Integer.class)));

    // Won't compile: map.putInstance(Double.class, new Long(42));
  }

  public void testNull() {
    try {
      map.putInstance((TypeToken) null, new Integer(1));
      fail();
    } catch (NullPointerException expected) {
    }
    map.putInstance(Integer.class, null);
    assertNull(map.get(Integer.class));
    assertNull(map.getInstance(Integer.class));

    map.putInstance(Long.class, null);
    assertNull(map.get(Long.class));
    assertNull(map.getInstance(Long.class));
  }

  public void testPrimitiveAndWrapper() {
    assertNull(map.getInstance(int.class));
    assertNull(map.getInstance(Integer.class));

    assertNull(map.putInstance(int.class, 0));
    assertNull(map.putInstance(Integer.class, 1));
    assertEquals(2, map.size());

    assertEquals(0, (int) map.getInstance(int.class));
    assertEquals(1, (int) map.getInstance(Integer.class));

    assertEquals(0, (int) map.putInstance(int.class, null));
    assertEquals(1, (int) map.putInstance(Integer.class, null));

    assertNull(map.getInstance(int.class));
    assertNull(map.getInstance(Integer.class));
    assertEquals(2, map.size());
  }

  public void testParameterizedType() {
    TypeToken<ImmutableList<Integer>> type = new TypeToken<ImmutableList<Integer>>() {};
    map.putInstance(type, ImmutableList.of(1));
    assertEquals(1, map.size());
    assertEquals(ImmutableList.of(1), map.getInstance(type));
  }

  public void testGeneriArrayType() {
    @SuppressWarnings("unchecked") // Trying to test generic array
    ImmutableList<Integer>[] array = new ImmutableList[] {ImmutableList.of(1)};
    TypeToken<ImmutableList<Integer>[]> type = new TypeToken<ImmutableList<Integer>[]>() {};
    map.putInstance(type, array);
    assertEquals(1, map.size());
    ASSERT.that(map.getInstance(type)).has().exactly(array[0]).inOrder();
  }

  public void testWildcardType() {
    TypeToken<ImmutableList<?>> type = new TypeToken<ImmutableList<?>>() {};
    map.putInstance(type, ImmutableList.of(1));
    assertEquals(1, map.size());
    assertEquals(ImmutableList.of(1), map.getInstance(type));
  }

  public void testGetInstance_withTypeVariable() {
    try {
      map.getInstance(this.<Number>anyIterableType());
      fail();
    } catch (IllegalArgumentException expected) {}
  }

  public void testPutInstance_withTypeVariable() {
    try {
      map.putInstance(this.<Integer>anyIterableType(), ImmutableList.of(1));
      fail();
    } catch (IllegalArgumentException expected) {}
  }

  private <T> TypeToken<Iterable<T>> anyIterableType() {
    return new TypeToken<Iterable<T>>() {};
  }
}