Test that we don't add new methods or supertypes to ListenableFuture.

Notably, we periodically get a suggestion of adding a `Duration` overload of `get`.

RELNOTES=n/a
PiperOrigin-RevId: 540662488

Author: cpovirk

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

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2023 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.assertWithMessage;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Future;
+import junit.framework.TestCase;
+
+/** Test for {@link ListenableFuture}. */
+public class ListenableFutureTest extends TestCase {
+  public void testNoNewApis() throws Exception {
+    assertWithMessage(
+            "Do not add new methods to ListenableFuture. Its API needs to continue to match the"
+                + " version we released in a separate artifact com.google.guava:listenablefuture.")
+        .that(ListenableFuture.class.getDeclaredMethods())
+        .asList()
+        .containsExactly(
+            ListenableFuture.class.getMethod("addListener", Runnable.class, Executor.class));
+    assertWithMessage(
+            "Do not add new supertypes to ListenableFuture. Its API needs to continue to match the"
+                + " version we released in a separate artifact com.google.guava:listenablefuture.")
+        .that(ListenableFuture.class.getInterfaces())
+        .asList()
+        .containsExactly(Future.class);
+  }
+}

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

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+/*
+ * Copyright (C) 2023 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.assertWithMessage;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Future;
+import junit.framework.TestCase;
+
+/** Test for {@link ListenableFuture}. */
+public class ListenableFutureTest extends TestCase {
+  public void testNoNewApis() throws Exception {
+    assertWithMessage(
+            "Do not add new methods to ListenableFuture. Its API needs to continue to match the"
+                + " version we released in a separate artifact com.google.guava:listenablefuture.")
+        .that(ListenableFuture.class.getDeclaredMethods())
+        .asList()
+        .containsExactly(
+            ListenableFuture.class.getMethod("addListener", Runnable.class, Executor.class));
+    assertWithMessage(
+            "Do not add new supertypes to ListenableFuture. Its API needs to continue to match the"
+                + " version we released in a separate artifact com.google.guava:listenablefuture.")
+        .that(ListenableFuture.class.getInterfaces())
+        .asList()
+        .containsExactly(Future.class);
+  }
+}