src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithIfUserTest.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.ir.optimize.string;

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.AssertUtils;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

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

  private final TestParameters parameters;

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

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

  @Test
  public void test() throws Exception {
    AssertUtils.assertFailsCompilationIf(
        parameters.isDexRuntime(),
        () -> {
          testForR8(parameters.getBackend())
              .addInnerClasses(StringBuilderWithIfUserTest.class)
              .addKeepMainRule(Main.class)
              .setMinApi(parameters.getApiLevel())
              .compile()
              .run(parameters.getRuntime(), Main.class)
              .assertSuccessWithOutputLines("Hello world!");
        });
  }

  static class Main {

    public static void main(String[] args) {
      StringBuilder builder = new StringBuilder();
      StringBuilder other = System.currentTimeMillis() > 0 ? new StringBuilder() : builder;
      builder.append("Hello world!");
      if (builder != other) {
        System.out.println(builder.toString());
      }
    }
  }
}