src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionOnFieldTest.java

// Copyright (c) 2022, 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.keepanno;

import static com.android.tools.r8.utils.codeinspector.Matchers.isAbsent;
import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
import static org.hamcrest.CoreMatchers.containsString;
import static org.hamcrest.MatcherAssert.assertThat;

import com.android.tools.r8.keepanno.annotations.KeepConstraint;
import com.android.tools.r8.keepanno.annotations.KeepTarget;
import com.android.tools.r8.keepanno.annotations.UsesReflection;
import com.android.tools.r8.utils.AndroidApiLevel;
import com.android.tools.r8.utils.StringUtils;
import com.android.tools.r8.utils.codeinspector.CodeInspector;
import com.google.common.collect.ImmutableList;
import java.lang.reflect.Field;
import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameter;

@RunWith(Parameterized.class)
public class KeepUsesReflectionOnFieldTest extends KeepAnnoTestBase {

  static final String EXPECTED = StringUtils.lines("Hello, world");

  @Parameter public KeepAnnoParameters parameters;

  @Parameterized.Parameters(name = "{0}")
  public static List<KeepAnnoParameters> data() {
    return createParameters(
        getTestParameters().withDefaultRuntimes().withApiLevel(AndroidApiLevel.B).build());
  }

  @Test
  public void test() throws Exception {
    testForKeepAnno(parameters)
        .addProgramClasses(getInputClasses())
        .addKeepMainRule(TestClass.class)
        .setExcludedOuterClass(getClass())
        .inspectOutputConfig(
            rules -> {
              assertThat(rules, containsString("context: " + descriptor(A.class) + "foo()V"));
              assertThat(rules, containsString("description: Keep the\\nstring-valued fields"));
            })
        .run(TestClass.class)
        .assertSuccessWithOutput(EXPECTED)
        .applyIf(parameters.isShrinker(), r -> r.inspect(this::checkOutput));
  }

  public List<Class<?>> getInputClasses() {
    return ImmutableList.of(TestClass.class, A.class);
  }

  private void checkOutput(CodeInspector inspector) {
    assertThat(inspector.clazz(A.class), isPresent());
    assertThat(inspector.clazz(A.class).uniqueFieldWithOriginalName("fieldA"), isPresent());
    assertThat(
        inspector.clazz(A.class).uniqueFieldWithOriginalName("fieldB"),
        parameters.isPG() ? isPresent() : isAbsent());
  }

  static class A {

    public String fieldA = "Hello, world";
    public Integer fieldB = 42;

    @UsesReflection(
        description = "Keep the\nstring-valued fields",
        value = {
          @KeepTarget(
              className = "com.android.tools.r8.keepanno.KeepUsesReflectionOnFieldTest$A",
              fieldType = "java.lang.String",
              constraints = {KeepConstraint.LOOKUP, KeepConstraint.FIELD_GET})
        })
    public void foo() throws Exception {
      for (Field field : getClass().getDeclaredFields()) {
        if (field.getType().equals(String.class)) {
          System.out.println(field.get(this));
        }
      }
    }
  }

  static class TestClass {

    public static void main(String[] args) throws Exception {
      new A().foo();
    }
  }
}