src/test/java/com/android/tools/r8/ir/optimize/classinliner/BuilderWithInheritanceTest.java

// Copyright (c) 2018, 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.ir.optimize.classinliner;

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

import com.android.tools.r8.NeverInline;
import com.android.tools.r8.NeverMerge;
import com.android.tools.r8.TestBase;
import com.android.tools.r8.utils.codeinspector.CodeInspector;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

/** Regression test for b/120182628. */
@RunWith(Parameterized.class)
public class BuilderWithInheritanceTest extends TestBase {

  private final Backend backend;

  @Parameters(name = "Backend: {0}")
  public static Backend[] data() {
    return Backend.values();
  }

  public BuilderWithInheritanceTest(Backend backend) {
    this.backend = backend;
  }

  @Test
  public void test() throws Exception {
    CodeInspector inspector =
        testForR8(backend)
            .addInnerClasses(BuilderWithInheritanceTest.class)
            .addKeepMainRule(TestClass.class)
            .enableInliningAnnotations()
            .enableMergeAnnotations()
            .run(TestClass.class)
            .assertSuccessWithOutput("42")
            .inspector();
    assertThat(inspector.clazz(Builder.class), isPresent());
  }

  static class TestClass {

    public static void main(String[] args) {
      A a = new Builder(42).build();
      System.out.print(a.get());
    }
  }

  static class A {

    private final int f;

    public A(int f) {
      this.f = f;
    }

    public int get() {
      return f;
    }
  }

  @NeverMerge
  static class BuilderBase {

    protected int f;

    public BuilderBase(int f) {
      this.f = f;
    }

    @NeverInline
    public static int get(BuilderBase obj) {
      return obj.f;
    }
  }

  static class Builder extends BuilderBase {

    public Builder(int f) {
      super(f);
    }

    public A build() {
      // After force inlining of get() there will be a field-read "this.f", which is not allowed by
      // the class inliner, because the class inliner only handles reads from fields that are
      // declared on Builder.
      return new A(get(this));
    }
  }
}