1 files changed, 61 insertions, 0 deletions
diff --git a/src/test/java/com/code_intelligence/jazzer/mutation/support/WeakIdentityHashMapTest.java b/src/test/java/com/code_intelligence/jazzer/mutation/support/WeakIdentityHashMapTest.java
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+++ b/src/test/java/com/code_intelligence/jazzer/mutation/support/WeakIdentityHashMapTest.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2023 Code Intelligence GmbH
+ *
+ * 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.code_intelligence.jazzer.mutation.support;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import java.util.Arrays;
+import java.util.List;
+import org.junit.jupiter.api.Test;
+
+class WeakIdentityHashMapTest {
+  private static void reachabilityFence(Object o) {
+    // Polyfill for JDK 9+ Reference.reachabilityFence:
+    // https://mail.openjdk.org/pipermail/core-libs-dev/2018-February/051312.html
+  }
+
+  @Test
+  void testWeakIdentityHashMap_hasIdentitySemantics() {
+    WeakIdentityHashMap<List<Integer>, String> map = new WeakIdentityHashMap<>();
+
+    List<Integer> list = Arrays.asList(1, 2);
+    map.put(list, "value");
+    assertThat(map.containsKey(list)).isTrue();
+
+    List<Integer> equalList = Arrays.asList(1, 2);
+    assertThat(map.containsKey(equalList)).isFalse();
+
+    reachabilityFence(list);
+  }
+
+  @Test
+  void testWeakIdentityHashMap_hasWeakSemantics() {
+    WeakIdentityHashMap<List<Integer>, String> map = new WeakIdentityHashMap<>();
+
+    List<Integer> list = Arrays.asList(1, 2);
+    map.put(list, "value");
+    assertThat(map.containsKey(list)).isTrue();
+    assertThat(map.size()).isEqualTo(1);
+    assertThat(map.isEmpty()).isFalse();
+
+    reachabilityFence(list);
+    map.collectKeysForTesting();
+
+    assertThat(map.size()).isEqualTo(0);
+    assertThat(map.isEmpty()).isTrue();
+  }
+}