| // Copyright (c) 2019, the R8 project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| package com.android.tools.r8.desugar.desugaredlibrary; |
| |
| import static org.junit.Assert.assertNotNull; |
| import static org.junit.Assert.assertTrue; |
| import static org.junit.Assert.fail; |
| |
| import com.android.tools.r8.TestParameters; |
| import com.android.tools.r8.TestParametersCollection; |
| import com.android.tools.r8.TestRuntime; |
| import com.android.tools.r8.TestRuntime.CfVm; |
| import com.android.tools.r8.utils.StringUtils; |
| import java.lang.reflect.Method; |
| import java.util.Collection; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.function.Predicate; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.Parameterized; |
| |
| /** |
| * This test checks that if a default interface method in a library is not overridden by a class |
| * method in the library, then a program defined maximally specific method becomes the target if |
| * present. |
| * |
| * <p>Concretely, Collection defines a default removeIf() method which is not overridden in either |
| * the List interface or the LinkedList class. Thus, any class deriving LinkedList for which |
| * removeIf is overridden or a new default method is added should target those extensions. |
| */ |
| @RunWith(Parameterized.class) |
| public class NoDefaultMethodOverrideInLibraryTest extends DesugaredLibraryTestBase { |
| |
| static final String EXPECTED = StringUtils.lines("MyIntegerList::removeIf", "false", "false"); |
| |
| private final TestParameters parameters; |
| |
| @Parameterized.Parameters(name = "{0}") |
| public static TestParametersCollection data() { |
| return getTestParameters().withAllRuntimes().withAllApiLevels().build(); |
| } |
| |
| public NoDefaultMethodOverrideInLibraryTest(TestParameters parameters) { |
| this.parameters = parameters; |
| } |
| |
| @Test |
| public void test() throws Exception { |
| TestRuntime systemRuntime = TestRuntime.getSystemRuntime(); |
| if (systemRuntime.isCf() && systemRuntime.asCf().isNewerThanOrEqual(CfVm.JDK8)) { |
| // This test assumes that the library defines a Collection class with a default removeIf. |
| Method removeIf = Collection.class.getDeclaredMethod("removeIf", Predicate.class); |
| assertNotNull(removeIf); |
| assertTrue(removeIf.isDefault()); |
| // Also, the LinkedList implementation does *not* define an override of removeIf. |
| try { |
| LinkedList.class.getDeclaredMethod("removeIf", Predicate.class); |
| fail("Unexpected defintion of removeIf on LinkedList"); |
| } catch (NoSuchMethodException e) { |
| // Expected. |
| } |
| } |
| if (parameters.isCfRuntime()) { |
| testForJvm() |
| .addInnerClasses(NoDefaultMethodOverrideInLibraryTest.class) |
| .run(parameters.getRuntime(), Main.class) |
| .assertSuccessWithOutput(EXPECTED); |
| } else { |
| testForD8() |
| .setMinApi(parameters.getApiLevel()) |
| .addInnerClasses(NoDefaultMethodOverrideInLibraryTest.class) |
| .enableCoreLibraryDesugaring(parameters.getApiLevel()) |
| .compile() |
| .addDesugaredCoreLibraryRunClassPath( |
| this::buildDesugaredLibrary, parameters.getApiLevel()) |
| .run(parameters.getRuntime(), Main.class) |
| .assertSuccessWithOutput(EXPECTED); |
| } |
| } |
| |
| // Custom list interface with a default method for removeIf. |
| interface MyIntegerList extends List<Integer> { |
| |
| @Override |
| default boolean removeIf(Predicate<? super Integer> filter) { |
| System.out.println("MyIntegerList::removeIf"); |
| return false; |
| } |
| } |
| |
| // Derived list with no override of removeIf but with a default method in MyIntegerList. |
| // The call will thus go to the maximally specific method, which is MyIntegerList::removeIf. |
| static class MyIntegerLinkedListWithoutOverride extends LinkedList<Integer> |
| implements MyIntegerList { |
| // No override of spliterator. |
| } |
| |
| // Derived list with an override of removeIf. The call must hit the classes override and that |
| // will explictly call the library default method (Collection.removeIf). |
| static class MyIntegerLinkedListWithOverride extends LinkedList<Integer> |
| implements MyIntegerList { |
| |
| @Override |
| public boolean removeIf(Predicate<? super Integer> filter) { |
| return super.removeIf(filter); |
| } |
| } |
| |
| static class Main { |
| |
| public static void main(String[] args) { |
| System.out.println(new MyIntegerLinkedListWithoutOverride().removeIf(e -> false)); |
| System.out.println(new MyIntegerLinkedListWithOverride().removeIf(e -> false)); |
| } |
| } |
| } |