src/test/java/com/android/tools/r8/classmerging/horizontal/interfaces/ClassHierarchyCycleAfterMergingTest.java

// Copyright (c) 2021, 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.classmerging.horizontal.interfaces;

import static com.android.tools.r8.utils.codeinspector.Matchers.isImplementing;
import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.assertFalse;

import com.android.tools.r8.NoHorizontalClassMerging;
import com.android.tools.r8.NoUnusedInterfaceRemoval;
import com.android.tools.r8.NoVerticalClassMerging;
import com.android.tools.r8.TestBase;
import com.android.tools.r8.TestParameters;
import com.android.tools.r8.TestParametersCollection;
import com.android.tools.r8.utils.codeinspector.ClassSubject;
import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

@RunWith(Parameterized.class)
public class ClassHierarchyCycleAfterMergingTest extends TestBase {

  private final TestParameters parameters;

  @Parameterized.Parameters(name = "{0}")
  public static TestParametersCollection data() {
    return getTestParameters().withAllRuntimesAndApiLevels().build();
  }

  public ClassHierarchyCycleAfterMergingTest(TestParameters parameters) {
    this.parameters = parameters;
  }

  @Test
  public void test() throws Exception {
    testForR8(parameters.getBackend())
        .addInnerClasses(getClass())
        .addKeepMainRule(Main.class)
        // I and J are not eligible for merging since that would lead to a cycle in the class
        // hierarchy.
        .addHorizontallyMergedClassesInspector(
            HorizontallyMergedClassesInspector::assertNoClassesMerged)
        .addOptionsModification(
            options -> {
              assertFalse(options.horizontalClassMergerOptions().isInterfaceMergingEnabled());
              options.horizontalClassMergerOptions().enableInterfaceMerging();
            })
        .enableNoHorizontalClassMergingAnnotations()
        .enableNoUnusedInterfaceRemovalAnnotations()
        .enableNoVerticalClassMergingAnnotations()
        .setMinApi(parameters.getApiLevel())
        .compile()
        .inspect(
            inspector -> {
              ClassSubject mainClassSubject = inspector.clazz(Main.class);
              assertThat(mainClassSubject, isPresent());
              assertThat(mainClassSubject, isImplementing(inspector.clazz(K.class)));
            })
        .run(parameters.getRuntime(), Main.class)
        .assertSuccessWithEmptyOutput();
  }

  static class Main implements K {

    public static void main(String[] args) {}
  }

  @NoUnusedInterfaceRemoval
  @NoVerticalClassMerging
  interface I {}

  @NoHorizontalClassMerging
  @NoUnusedInterfaceRemoval
  @NoVerticalClassMerging
  interface J extends I {}

  @NoUnusedInterfaceRemoval
  @NoVerticalClassMerging
  interface K extends J {}
}