/*
* Copyright (C) 2007 Google Inc.
*
* 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.collect;
import com.google.common.base.Function;
import com.google.common.base.Functions;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.testing.IteratorFeature.UNMODIFIABLE;
import com.google.common.collect.testing.IteratorTester;
import com.google.common.collect.testing.ListTestSuiteBuilder;
import com.google.common.collect.testing.TestStringListGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.ListFeature;
import static com.google.common.testing.junit3.JUnitAsserts.assertContentsInOrder;
import com.google.common.testutils.NullPointerTester;
import com.google.common.testutils.SerializableTester;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.easymock.classextension.EasyMock;
import java.io.Serializable;
import java.util.ArrayList;
import static java.util.Arrays.asList;
import java.util.Collection;
import java.util.Collections;
import static java.util.Collections.singletonList;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;
import java.util.RandomAccess;
/**
* Unit test for {@code Lists}.
*
* @author Kevin Bourrillion
* @author Mike Bostock
* @author Jared Levy
*/
public class ListsTest extends TestCase {
private static final Collection<Integer> SOME_COLLECTION
= asList(0, 1, 1);
private static final Iterable<Integer> SOME_ITERABLE = new SomeIterable();
private static class SomeIterable implements Iterable<Integer>, Serializable {
public Iterator<Integer> iterator() {
return SOME_COLLECTION.iterator();
}
private static final long serialVersionUID = 0;
}
private static final List<Integer> SOME_LIST
= Lists.newArrayList(1, 2, 3, 4);
private static final List<Integer> SOME_SEQUENTIAL_LIST
= Lists.newLinkedList(asList(1, 2, 3, 4));
private static final List<String> SOME_STRING_LIST
= asList("1", "2", "3", "4");
private static final Function<Number, String> SOME_FUNCTION
= new SomeFunction();
private static class SomeFunction
implements Function<Number, String>, Serializable {
public String apply(Number n) {
return String.valueOf(n);
}
private static final long serialVersionUID = 0;
}
public static Test suite() {
TestSuite suite = new TestSuite();
suite.addTestSuite(ListsTest.class);
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
String[] rest = new String[elements.length - 1];
System.arraycopy(elements, 1, rest, 0, elements.length - 1);
return Lists.asList(elements[0], rest);
}
})
.named("Lists.asList, 2 parameter")
.withFeatures(CollectionSize.SEVERAL, CollectionSize.ONE,
CollectionFeature.ALLOWS_NULL_VALUES)
.createTestSuite());
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
String[] rest = new String[elements.length - 2];
System.arraycopy(elements, 2, rest, 0, elements.length - 2);
return Lists.asList(elements[0], elements[1], rest);
}
})
.named("Lists.asList, 3 parameter")
.withFeatures(CollectionSize.SEVERAL,
CollectionFeature.ALLOWS_NULL_VALUES)
.createTestSuite());
final Function<String, String> removeFirst
= new Function<String, String>() {
public String apply(String from) {
return (from.length() == 0) ? from : from.substring(1);
}
};
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
List<String> fromList = Lists.newArrayList();
for (String element : elements) {
fromList.add("q" + checkNotNull(element));
}
return Lists.transform(fromList, removeFirst);
}
})
.named("Lists.transform, random access, no nulls")
.withFeatures(CollectionSize.ANY,
ListFeature.REMOVE_OPERATIONS)
.createTestSuite());
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
List<String> fromList = Lists.newLinkedList();
for (String element : elements) {
fromList.add("q" + checkNotNull(element));
}
return Lists.transform(fromList, removeFirst);
}
})
.named("Lists.transform, sequential access, no nulls")
.withFeatures(CollectionSize.ANY,
ListFeature.REMOVE_OPERATIONS)
.createTestSuite());
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
List<String> fromList = Lists.newArrayList(elements);
return Lists.transform(fromList, Functions.<String>identity());
}
})
.named("Lists.transform, random access, nulls")
.withFeatures(CollectionSize.ANY,
ListFeature.REMOVE_OPERATIONS,
CollectionFeature.ALLOWS_NULL_VALUES)
.createTestSuite());
suite.addTest(ListTestSuiteBuilder.using(new TestStringListGenerator() {
@Override protected List<String> create(String[] elements) {
List<String> fromList =
Lists.newLinkedList(asList(elements));
return Lists.transform(fromList, Functions.<String>identity());
}
})
.named("Lists.transform, sequential access, nulls")
.withFeatures(CollectionSize.ANY,
ListFeature.REMOVE_OPERATIONS,
CollectionFeature.ALLOWS_NULL_VALUES)
.createTestSuite());
return suite;
}
public void testIllustrateVarargsWeirdness() {
String[] array = { "foo", "bar" };
List<String> list = ImmutableList.of(array);
// Fortunately, this does what the caller clearly intended
assertEquals(2, list.size());
// If the list-of-array is desired, a special method type parameter must be
// inserted or the code won't compile.
List<String[]> listOfArray = ImmutableList.<String[]>of(array);
// This also behaves as expected
assertEquals(1, listOfArray.size());
// It's pretty strange that the selection of overload can depend on the
// type parameter given. But what if raw types are used?
@SuppressWarnings("unchecked")
List whatIsThis = ImmutableList.of(array);
// In most cases I think this will be what the caller intended. If not...
// well, ya shoulda used the generics, bub.
assertEquals(2, whatIsThis.size());
// Unfortunately, the below will blow up at runtime
// But hey, can't say the compiler didn't warn ya
try {
ImmutableList.of((String[]) null);
fail();
} catch (NullPointerException expected) {
}
}
public void testNewArrayListEmpty() {
ArrayList<Integer> list = Lists.newArrayList();
assertEquals(Collections.emptyList(), list);
}
public void testNewArrayListWithCapacity() {
ArrayList<Integer> list = Lists.newArrayListWithCapacity(0);
assertEquals(Collections.emptyList(), list);
ArrayList<Integer> bigger = Lists.newArrayListWithCapacity(256);
assertEquals(Collections.emptyList(), bigger);
}
public void testNewArrayListWithCapacity_negative() {
try {
Lists.newArrayListWithCapacity(-1);
fail();
} catch (IllegalArgumentException expected) {
}
}
public void testNewArrayListWithExpectedSize() {
ArrayList<Integer> list = Lists.newArrayListWithExpectedSize(0);
assertEquals(Collections.emptyList(), list);
ArrayList<Integer> bigger = Lists.newArrayListWithExpectedSize(256);
assertEquals(Collections.emptyList(), bigger);
}
public void testNewArrayListWithExpectedSize_negative() {
try {
Lists.newArrayListWithExpectedSize(-1);
fail();
} catch (IllegalArgumentException expected) {
}
}
public void testNewArrayListVarArgs() {
ArrayList<Integer> list = Lists.newArrayList(0, 1, 1);
assertEquals(SOME_COLLECTION, list);
}
public void testComputeArrayListCapacity() {
assertEquals(5, Lists.computeArrayListCapacity(0));
assertEquals(13, Lists.computeArrayListCapacity(8));
assertEquals(89, Lists.computeArrayListCapacity(77));
assertEquals(22000005, Lists.computeArrayListCapacity(20000000));
assertEquals(Integer.MAX_VALUE,
Lists.computeArrayListCapacity(Integer.MAX_VALUE - 1000));
}
public void testNewArrayListFromCollection() {
ArrayList<Integer> list = Lists.newArrayList(SOME_COLLECTION);
assertEquals(SOME_COLLECTION, list);
}
public void testNewArrayListFromIterable() {
ArrayList<Integer> list = Lists.newArrayList(SOME_ITERABLE);
assertEquals(SOME_COLLECTION, list);
}
public void testNewArrayListFromIterator() {
ArrayList<Integer> list = Lists.newArrayList(SOME_COLLECTION.iterator());
assertEquals(SOME_COLLECTION, list);
}
public void testNewLinkedListEmpty() {
LinkedList<Integer> list = Lists.newLinkedList();
assertEquals(Collections.emptyList(), list);
}
public void testNewLinkedListFromCollection() {
LinkedList<Integer> list = Lists.newLinkedList(SOME_COLLECTION);
assertEquals(SOME_COLLECTION, list);
}
public void testNewLinkedListFromIterable() {
LinkedList<Integer> list = Lists.newLinkedList(SOME_ITERABLE);
assertEquals(SOME_COLLECTION, list);
}
public void testNullPointerExceptions() throws Exception {
NullPointerTester tester = new NullPointerTester();
tester.testAllPublicStaticMethods(Lists.class);
}
/**
* This is just here to illustrate how {@code Arrays#asList} differs from
* {@code Lists#newArrayList}.
*/
public void testArraysAsList() {
List<String> ourWay = Lists.newArrayList("foo", "bar", "baz");
List<String> otherWay = asList("foo", "bar", "baz");
// They're logically equal
assertEquals(ourWay, otherWay);
// The result of Arrays.asList() is mutable
otherWay.set(0, "FOO");
assertEquals("FOO", otherWay.get(0));
// But it can't grow
try {
otherWay.add("nope");
fail("no exception thrown");
} catch (UnsupportedOperationException expected) {
}
// And it can't shrink
try {
otherWay.remove(2);
fail("no exception thrown");
} catch (UnsupportedOperationException expected) {
}
}
public void testAsList1() throws Exception {
List<String> list = Lists.asList("foo", new String[] { "bar", "baz" });
checkFooBarBazList(list);
SerializableTester.reserializeAndAssert(list);
assertTrue(list instanceof RandomAccess);
new IteratorTester<String>(5, UNMODIFIABLE,
asList("foo", "bar", "baz"),
IteratorTester.KnownOrder.KNOWN_ORDER) {
@Override protected Iterator<String> newTargetIterator() {
return Lists.asList("foo", new String[] {"bar", "baz"}).iterator();
}
}.test();
}
private void checkFooBarBazList(List<String> list) {
assertContentsInOrder(list, "foo", "bar", "baz");
assertEquals(3, list.size());
assertIndexIsOutOfBounds(list, -1);
assertEquals("foo", list.get(0));
assertEquals("bar", list.get(1));
assertEquals("baz", list.get(2));
assertIndexIsOutOfBounds(list, 3);
}
public void testAsList1Small() throws Exception {
List<String> list = Lists.asList("foo", new String[0]);
assertContentsInOrder(list, "foo");
assertEquals(1, list.size());
assertIndexIsOutOfBounds(list, -1);
assertEquals("foo", list.get(0));
assertIndexIsOutOfBounds(list, 1);
assertTrue(list instanceof RandomAccess);
new IteratorTester<String>(3, UNMODIFIABLE, singletonList("foo"),
IteratorTester.KnownOrder.KNOWN_ORDER) {
@Override protected Iterator<String> newTargetIterator() {
return Lists.asList("foo", new String[0]).iterator();
}
}.test();
}
public void testAsList2() throws Exception {
List<String> list = Lists.asList("foo", "bar", new String[] { "baz" });
checkFooBarBazList(list);
assertTrue(list instanceof RandomAccess);
new IteratorTester<String>(5, UNMODIFIABLE, asList("foo", "bar",
"baz"), IteratorTester.KnownOrder.KNOWN_ORDER) {
@Override protected Iterator<String> newTargetIterator() {
return Lists.asList("foo", "bar", new String[] {"baz"}).iterator();
}
}.test();
}
public void testAsList2Small() throws Exception {
List<String> list = Lists.asList("foo", "bar", new String[0]);
assertContentsInOrder(list, "foo", "bar");
assertEquals(2, list.size());
assertIndexIsOutOfBounds(list, -1);
assertEquals("foo", list.get(0));
assertEquals("bar", list.get(1));
assertIndexIsOutOfBounds(list, 2);
SerializableTester.reserializeAndAssert(list);
assertTrue(list instanceof RandomAccess);
new IteratorTester<String>(5, UNMODIFIABLE, asList("foo", "bar"),
IteratorTester.KnownOrder.KNOWN_ORDER) {
@Override protected Iterator<String> newTargetIterator() {
return Lists.asList("foo", "bar", new String[0]).iterator();
}
}.test();
}
private static void assertIndexIsOutOfBounds(List<String> list, int index) {
try {
list.get(index);
fail();
} catch (IndexOutOfBoundsException expected) {
}
}
public void testTransformEqualityRandomAccess() {
List<String> list = Lists.transform(SOME_LIST, SOME_FUNCTION);
assertEquals(SOME_STRING_LIST, list);
SerializableTester.reserializeAndAssert(list);
}
public void testTransformEqualitySequential() {
List<String> list = Lists.transform(SOME_SEQUENTIAL_LIST, SOME_FUNCTION);
assertEquals(SOME_STRING_LIST, list);
SerializableTester.reserializeAndAssert(list);
}
public void testTransformHashCodeRandomAccess() {
List<String> list = Lists.transform(SOME_LIST, SOME_FUNCTION);
assertEquals(SOME_STRING_LIST.hashCode(), list.hashCode());
}
public void testTransformHashCodeSequential() {
List<String> list = Lists.transform(SOME_SEQUENTIAL_LIST, SOME_FUNCTION);
assertEquals(SOME_STRING_LIST.hashCode(), list.hashCode());
}
public void testTransformModifiableRandomAccess() {
List<Integer> fromList = Lists.newArrayList(SOME_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformModifiable(list);
}
public void testTransformModifiableSequential() {
List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformModifiable(list);
}
private static void assertTransformModifiable(List<String> list) {
try {
list.add("5");
fail("transformed list is addable");
} catch (UnsupportedOperationException expected) {}
list.remove(0);
assertEquals(asList("2", "3", "4"), list);
list.remove("3");
assertEquals(asList("2", "4"), list);
try {
list.set(0, "5");
fail("transformed list is setable");
} catch (UnsupportedOperationException expected) {}
list.clear();
assertEquals(Collections.emptyList(), list);
}
public void testTransformViewRandomAccess() {
List<Integer> fromList = Lists.newArrayList(SOME_LIST);
List<String> toList = Lists.transform(fromList, SOME_FUNCTION);
assertTransformView(fromList, toList);
}
public void testTransformViewSequential() {
List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
List<String> toList = Lists.transform(fromList, SOME_FUNCTION);
assertTransformView(fromList, toList);
}
private static void assertTransformView(List<Integer> fromList,
List<String> toList) {
/* fromList modifications reflected in toList */
fromList.set(0, 5);
assertEquals(asList("5", "2", "3", "4"), toList);
fromList.add(6);
assertEquals(asList("5", "2", "3", "4", "6"), toList);
fromList.remove(Integer.valueOf(2));
assertEquals(asList("5", "3", "4", "6"), toList);
fromList.remove(2);
assertEquals(asList("5", "3", "6"), toList);
/* toList modifications reflected in fromList */
toList.remove(2);
assertEquals(asList(5, 3), fromList);
toList.remove("5");
assertEquals(asList(3), fromList);
toList.clear();
assertEquals(Collections.emptyList(), fromList);
}
public void testTransformRandomAccess() {
List<String> list = Lists.transform(SOME_LIST, SOME_FUNCTION);
assertTrue(list instanceof RandomAccess);
}
public void testTransformSequential() {
List<String> list = Lists.transform(SOME_SEQUENTIAL_LIST, SOME_FUNCTION);
assertFalse(list instanceof RandomAccess);
}
public void testTransformListIteratorRandomAccess() {
List<Integer> fromList = Lists.newArrayList(SOME_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformListIterator(list);
}
public void testTransformListIteratorSequential() {
List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformListIterator(list);
}
private static void assertTransformListIterator(List<String> list) {
ListIterator<String> iterator = list.listIterator(1);
assertEquals(1, iterator.nextIndex());
assertEquals("2", iterator.next());
assertEquals("3", iterator.next());
assertEquals("4", iterator.next());
assertEquals(4, iterator.nextIndex());
try {
iterator.next();
fail("did not detect end of list");
} catch (NoSuchElementException expected) {}
assertEquals(3, iterator.previousIndex());
assertEquals("4", iterator.previous());
assertEquals("3", iterator.previous());
assertEquals("2", iterator.previous());
assertTrue(iterator.hasPrevious());
assertEquals("1", iterator.previous());
assertFalse(iterator.hasPrevious());
assertEquals(-1, iterator.previousIndex());
try {
iterator.previous();
fail("did not detect beginning of list");
} catch (NoSuchElementException expected) {}
iterator.remove();
assertEquals(asList("2", "3", "4"), list);
assertFalse(list.isEmpty());
// An UnsupportedOperationException or IllegalStateException may occur.
try {
iterator.add("1");
fail("transformed list iterator is addable");
} catch (UnsupportedOperationException expected) {
} catch (IllegalStateException expected) {}
try {
iterator.set("1");
fail("transformed list iterator is settable");
} catch (UnsupportedOperationException expected) {
} catch (IllegalStateException expected) {}
}
public void testTransformIteratorRandomAccess() {
List<Integer> fromList = Lists.newArrayList(SOME_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformIterator(list);
}
public void testTransformIteratorSequential() {
List<Integer> fromList = Lists.newLinkedList(SOME_SEQUENTIAL_LIST);
List<String> list = Lists.transform(fromList, SOME_FUNCTION);
assertTransformIterator(list);
}
/**
* We use this class to avoid the need to suppress generics checks with
* easy mock.
*/
private interface IntegerList extends List<Integer> {}
/**
* This test depends on the fact that {@code AbstractSequentialList.iterator}
* transforms the {@code iterator()} call into a call on {@code
* listIterator(int)}. This is fine because the behavior is clearly
* documented so it's not expected to change.
*/
public void testTransformedSequentialIterationUsesBackingListIterationOnly() {
List<Integer> randomAccessList = Lists.newArrayList(SOME_SEQUENTIAL_LIST);
ListIterator<Integer> sampleListIterator =
SOME_SEQUENTIAL_LIST.listIterator();
List<Integer> listMock = EasyMock.createMock(IntegerList.class);
EasyMock.expect(listMock.listIterator(0)).andReturn(sampleListIterator);
EasyMock.replay(listMock);
List<String> transform = Lists.transform(listMock, SOME_FUNCTION);
assertTrue(Iterables.elementsEqual(
transform, Lists.transform(randomAccessList, SOME_FUNCTION)));
EasyMock.verify(listMock);
}
private static void assertTransformIterator(List<String> list) {
Iterator<String> iterator = list.iterator();
assertTrue(iterator.hasNext());
assertEquals("1", iterator.next());
assertTrue(iterator.hasNext());
assertEquals("2", iterator.next());
assertTrue(iterator.hasNext());
assertEquals("3", iterator.next());
assertTrue(iterator.hasNext());
assertEquals("4", iterator.next());
assertFalse(iterator.hasNext());
try {
iterator.next();
fail("did not detect end of list");
} catch (NoSuchElementException expected) {}
iterator.remove();
assertEquals(asList("1", "2", "3"), list);
assertFalse(iterator.hasNext());
}
public void testPartition_badSize() {
List<Integer> source = Collections.singletonList(1);
try {
Lists.partition(source, 0);
fail();
} catch (IllegalArgumentException expected) {
}
}
public void testPartition_empty() {
List<Integer> source = Collections.emptyList();
List<List<Integer>> partitions = Lists.partition(source, 1);
assertTrue(partitions.isEmpty());
assertEquals(0, partitions.size());
}
public void testPartition_1_1() {
List<Integer> source = Collections.singletonList(1);
List<List<Integer>> partitions = Lists.partition(source, 1);
assertEquals(1, partitions.size());
assertEquals(Collections.singletonList(1), partitions.get(0));
}
public void testPartition_1_2() {
List<Integer> source = Collections.singletonList(1);
List<List<Integer>> partitions = Lists.partition(source, 2);
assertEquals(1, partitions.size());
assertEquals(Collections.singletonList(1), partitions.get(0));
}
public void testPartition_2_1() {
List<Integer> source = asList(1, 2);
List<List<Integer>> partitions = Lists.partition(source, 1);
assertEquals(2, partitions.size());
assertEquals(Collections.singletonList(1), partitions.get(0));
assertEquals(Collections.singletonList(2), partitions.get(1));
}
public void testPartition_3_2() {
List<Integer> source = asList(1, 2, 3);
List<List<Integer>> partitions = Lists.partition(source, 2);
assertEquals(2, partitions.size());
assertEquals(asList(1, 2), partitions.get(0));
assertEquals(asList(3), partitions.get(1));
}
public void testPartitionRandomAccessTrue() {
List<Integer> source = asList(1, 2, 3);
List<List<Integer>> partitions = Lists.partition(source, 2);
assertTrue(partitions instanceof RandomAccess);
assertTrue(partitions.get(0) instanceof RandomAccess);
assertTrue(partitions.get(1) instanceof RandomAccess);
}
public void testPartitionRandomAccessFalse() {
List<Integer> source = Lists.newLinkedList(asList(1, 2, 3));
List<List<Integer>> partitions = Lists.partition(source, 2);
assertFalse(partitions instanceof RandomAccess);
assertFalse(partitions.get(0) instanceof RandomAccess);
assertFalse(partitions.get(1) instanceof RandomAccess);
}
// TODO: use the ListTestSuiteBuilder
public void testPartition_view() {
List<Integer> list = asList(1, 2, 3);
List<List<Integer>> partitions = Lists.partition(list, 3);
// Changes before the partition is retrieved are reflected
list.set(0, 3);
Iterator<List<Integer>> iterator = partitions.iterator();
// Changes before the partition is retrieved are reflected
list.set(1, 4);
List<Integer> first = iterator.next();
// Changes after are too (unlike Iterables.partition)
list.set(2, 5);
assertEquals(asList(3, 4, 5), first);
// Changes to a sublist also write through to the original list
first.set(1, 6);
assertEquals(asList(3, 6, 5), list);
}
}