src/test/java/com/android/tools/r8/optimize/atomicfieldupdater/AtomicFieldUpdaterCatchUsageTest.java

// Copyright (c) 2026, 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.optimize.atomicfieldupdater;

import static com.android.tools.r8.DiagnosticsMatcher.diagnosticMessage;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.core.IsNot.not;
import static org.hamcrest.core.StringContains.containsString;

import com.android.tools.r8.TestParameters;
import com.android.tools.r8.TestParametersCollection;
import com.android.tools.r8.utils.codeinspector.MethodSubject;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)
public class AtomicFieldUpdaterCatchUsageTest extends AtomicFieldUpdaterBase {

  public AtomicFieldUpdaterCatchUsageTest(TestParameters parameters) {
    super(parameters);
  }

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

  @Test
  public void testR8() throws Exception {
    Class<TestClass> testClass = TestClass.class;
    testForR8(parameters)
        .apply(this::enableAtomicFieldUpdaterWithInfo)
        .addProgramClasses(testClass)
        .addKeepMainRule(testClass)
        .compile()
        .inspectDiagnosticMessagesIf(
            isOptimizationOn(),
            diagnostics ->
                diagnostics.assertInfosMatch(
                    diagnosticMessage(containsString("Can instrument")),
                    diagnosticMessage(containsString("Cannot optimize")),
                    diagnosticMessage(containsString("Cannot optimize")),
                    diagnosticMessage(containsString("Cannot optimize")),
                    diagnosticMessage(containsString("Cannot remove"))))
        .inspect(
            inspector -> {
              MethodSubject method = inspector.clazz(testClass).mainMethod();
              assertThat(method, not(INVOKES_UNSAFE));
            })
        .run(parameters.getRuntime(), testClass)
        .assertSuccessWithOutputLines("Hello!!");
  }

  // Corresponding to simple kotlin usage of `atomic("Hello")` via atomicfu.
  public static class TestClass {

    private volatile Object myString;

    private static final AtomicReferenceFieldUpdater<TestClass, Object> myString$FU;

    static {
      myString$FU =
          AtomicReferenceFieldUpdater.newUpdater(TestClass.class, Object.class, "myString");
    }

    public TestClass() {
      super();
      myString = "Hello";
    }

    public static void main(String[] args) {
      TestClass instance = new TestClass();
      try {
        Object old = myString$FU.getAndSet(instance, "World");
        myString$FU.set(instance, old.toString() + "!!");
        System.out.println(myString$FU.get(instance));
      } catch (Exception e) {
        // The try block never throws. This is here to test the rewriting with catch handlers.
        throw new RuntimeException(e);
      }
    }
  }
}