Test which AtomicHelper is used by AggregateFutureState, including after Android optimization.

This is similar to cl/742859752 and cl/742922048, which did the same for `AbstractFutureState`.

RELNOTES=n/a
PiperOrigin-RevId: 744264888

Author: cpovirk

android/guava-tests/test/com/google/common/util/concurrent/AggregateFutureStateDefaultAtomicHelperTest.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2015 The Guava Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.google.common.util.concurrent;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import junit.framework.TestCase;
+import org.jspecify.annotations.NullUnmarked;
+
+/**
+ * Tests that {@link AggregateFutureState} uses the expected {@code AtomicHelper} implementation.
+ *
+ * <p>We have more thorough testing of {@code AtomicHelper} implementations in {@link
+ * AggregateFutureStateFallbackAtomicHelperTest}. The advantage to this test is that it can run
+ * under Android.
+ */
+@NullUnmarked
+public class AggregateFutureStateDefaultAtomicHelperTest extends TestCase {
+  public void testUsingExpectedAtomicHelper() throws Exception {
+    assertThat(AggregateFutureState.atomicHelperTypeForTest()).isEqualTo("SafeAtomicHelper");
+  }
+}

android/guava/src/com/google/common/util/concurrent/AggregateFutureState.java

@@ -20,6 +20,7 @@
 import static java.util.concurrent.atomic.AtomicReferenceFieldUpdater.newUpdater;
 
 import com.google.common.annotations.GwtCompatible;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.j2objc.annotations.ReflectionSupport;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
@@ -143,13 +144,20 @@ final void clearSeenExceptions() {
     seenExceptions = null;
   }
 
+  @VisibleForTesting
+  static String atomicHelperTypeForTest() {
+    return ATOMIC_HELPER.atomicHelperTypeForTest();
+  }
+
   private abstract static class AtomicHelper {
     /** Atomic compare-and-set of the {@link AggregateFutureState#seenExceptions} field. */
     abstract void compareAndSetSeenExceptions(
         AggregateFutureState<?> state, @Nullable Set<Throwable> expect, Set<Throwable> update);
 
     /** Atomic decrement-and-get of the {@link AggregateFutureState#remaining} field. */
     abstract int decrementAndGetRemainingCount(AggregateFutureState<?> state);
+
+    abstract String atomicHelperTypeForTest();
   }
 
   private static final class SafeAtomicHelper extends AtomicHelper {
@@ -170,6 +178,11 @@ void compareAndSetSeenExceptions(
     int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
       return remainingCountUpdater.decrementAndGet(state);
     }
+
+    @Override
+    String atomicHelperTypeForTest() {
+      return "SafeAtomicHelper";
+    }
   }
 
   private static final class SynchronizedAtomicHelper extends AtomicHelper {
@@ -189,6 +202,11 @@ int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
         return --state.remaining;
       }
     }
+
+    @Override
+    String atomicHelperTypeForTest() {
+      return "SynchronizedAtomicHelper";
+    }
   }
 
   /**

guava-tests/test/com/google/common/util/concurrent/AggregateFutureStateDefaultAtomicHelperTest.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2015 The Guava Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.google.common.util.concurrent;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import junit.framework.TestCase;
+import org.jspecify.annotations.NullUnmarked;
+
+/**
+ * Tests that {@link AggregateFutureState} uses the expected {@code AtomicHelper} implementation.
+ *
+ * <p>We have more thorough testing of {@code AtomicHelper} implementations in {@link
+ * AggregateFutureStateFallbackAtomicHelperTest}. The advantage to this test is that it can run
+ * under Android.
+ */
+@NullUnmarked
+public class AggregateFutureStateDefaultAtomicHelperTest extends TestCase {
+  public void testUsingExpectedAtomicHelper() throws Exception {
+    assertThat(AggregateFutureState.atomicHelperTypeForTest()).isEqualTo("SafeAtomicHelper");
+  }
+}

guava/src/com/google/common/util/concurrent/AggregateFutureState.java

@@ -20,6 +20,7 @@
 import static java.util.concurrent.atomic.AtomicReferenceFieldUpdater.newUpdater;
 
 import com.google.common.annotations.GwtCompatible;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.j2objc.annotations.ReflectionSupport;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
@@ -143,13 +144,20 @@ final void clearSeenExceptions() {
     seenExceptions = null;
   }
 
+  @VisibleForTesting
+  static String atomicHelperTypeForTest() {
+    return ATOMIC_HELPER.atomicHelperTypeForTest();
+  }
+
   private abstract static class AtomicHelper {
     /** Atomic compare-and-set of the {@link AggregateFutureState#seenExceptions} field. */
     abstract void compareAndSetSeenExceptions(
         AggregateFutureState<?> state, @Nullable Set<Throwable> expect, Set<Throwable> update);
 
     /** Atomic decrement-and-get of the {@link AggregateFutureState#remaining} field. */
     abstract int decrementAndGetRemainingCount(AggregateFutureState<?> state);
+
+    abstract String atomicHelperTypeForTest();
   }
 
   private static final class SafeAtomicHelper extends AtomicHelper {
@@ -170,6 +178,11 @@ void compareAndSetSeenExceptions(
     int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
       return remainingCountUpdater.decrementAndGet(state);
     }
+
+    @Override
+    String atomicHelperTypeForTest() {
+      return "SafeAtomicHelper";
+    }
   }
 
   private static final class SynchronizedAtomicHelper extends AtomicHelper {
@@ -189,6 +202,11 @@ int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
         return --state.remaining;
       }
     }
+
+    @Override
+    String atomicHelperTypeForTest() {
+      return "SynchronizedAtomicHelper";
+    }
   }
 
   /**