src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllOptionalConversionTest.java

// 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.conversiontests;

import com.android.tools.r8.TestRuntime.DexRuntime;
import com.android.tools.r8.ToolHelper.DexVm;
import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
import com.android.tools.r8.utils.AndroidApiLevel;
import com.android.tools.r8.utils.StringUtils;
import java.nio.file.Path;
import java.util.Optional;
import java.util.OptionalDouble;
import java.util.OptionalInt;
import java.util.OptionalLong;
import org.junit.Test;

public class AllOptionalConversionTest extends DesugaredLibraryTestBase {

  @Test
  public void testRewrittenAPICalls() throws Exception {
    Path customLib = testForD8().addProgramClasses(CustomLibClass.class).compile().writeToZip();
    testForD8()
        .setMinApi(AndroidApiLevel.B)
        .addProgramClasses(Executor.class)
        .addLibraryClasses(CustomLibClass.class)
        .enableCoreLibraryDesugaring(AndroidApiLevel.B)
        .compile()
        .addDesugaredCoreLibraryRunClassPath(this::buildDesugaredLibrary, AndroidApiLevel.B)
        .addRunClasspathFiles(customLib)
        .run(new DexRuntime(DexVm.ART_9_0_0_HOST), Executor.class)
        .assertSuccessWithOutput(
            StringUtils.lines(
                "Optional[value]",
                "OptionalDouble[1.0]",
                "OptionalInt[1]",
                "OptionalLong[1]",
                "Optional[value]",
                "value"));
  }

  static class Executor {

    public static void main(String[] args) {
      returnValueUsed();
      returnValueUnused();
      virtualMethods();
    }

    @SuppressWarnings("all")
    public static void returnValueUsed() {
      System.out.println(CustomLibClass.mix(Optional.empty(), Optional.of("value")));
      System.out.println(CustomLibClass.mix(OptionalDouble.empty(), OptionalDouble.of(1.0)));
      System.out.println(CustomLibClass.mix(OptionalInt.empty(), OptionalInt.of(1)));
      System.out.println(CustomLibClass.mix(OptionalLong.empty(), OptionalLong.of(1L)));
    }

    @SuppressWarnings("all")
    public static void returnValueUnused() {
      CustomLibClass.mix(Optional.empty(), Optional.of("value"));
      CustomLibClass.mix(OptionalDouble.empty(), OptionalDouble.of(1.0));
      CustomLibClass.mix(OptionalInt.empty(), OptionalInt.of(1));
      CustomLibClass.mix(OptionalLong.empty(), OptionalLong.of(1L));
    }

    public static void virtualMethods() {
      CustomLibClass customLibClass = new CustomLibClass();
      Optional<String> optionalValue = Optional.of("value");
      customLibClass.virtual(optionalValue);
      customLibClass.virtualString(optionalValue);
      System.out.println(customLibClass.virtual(optionalValue));
      System.out.println(customLibClass.virtualString(optionalValue));
    }
  }

  // This class will be put at compilation time as library and on the runtime class path.
  // This class is convenient for easy testing. Each method plays the role of methods in the
  // platform APIs for which argument/return values need conversion.
  static class CustomLibClass {

    @SuppressWarnings("all")
    public static <T> Optional<T> mix(Optional<T> optional1, Optional<T> optional2) {
      return optional1.isPresent() ? optional1 : optional2;
    }

    @SuppressWarnings("all")
    public static OptionalDouble mix(OptionalDouble optional1, OptionalDouble optional2) {
      return optional1.isPresent() ? optional1 : optional2;
    }

    @SuppressWarnings("all")
    public static OptionalInt mix(OptionalInt optional1, OptionalInt optional2) {
      return optional1.isPresent() ? optional1 : optional2;
    }

    @SuppressWarnings("all")
    public static OptionalLong mix(OptionalLong optional1, OptionalLong optional2) {
      return optional1.isPresent() ? optional1 : optional2;
    }

    @SuppressWarnings("all")
    public Optional<String> virtual(Optional<String> optional) {
      return optional;
    }

    @SuppressWarnings("all")
    public String virtualString(Optional<String> optional) {
      return optional.get();
    }
  }
}