1 files changed, 109 insertions, 0 deletions
diff --git a/src/test/java/org/apache/commons/lang3/concurrent/MemoizerFunctionTest.java b/src/test/java/org/apache/commons/lang3/concurrent/MemoizerFunctionTest.java
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index 000000000..4b2ff52dc
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+++ b/src/test/java/org/apache/commons/lang3/concurrent/MemoizerFunctionTest.java
@@ -0,0 +1,109 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.commons.lang3.concurrent;
+
+import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.replay;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.function.Function;
+
+import org.apache.commons.lang3.AbstractLangTest;
+import org.easymock.EasyMock;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class MemoizerFunctionTest extends AbstractLangTest {
+
+    private Function<Integer, Integer> function;
+
+    @BeforeEach
+    public void setUpComputableMock() {
+        function = EasyMock.mock(Function.class);
+    }
+
+    @Test
+    public void testDefaultBehaviourNotToRecalculateExecutionExceptions() throws Exception {
+        final Integer input = 1;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function);
+        final IllegalArgumentException interruptedException = new IllegalArgumentException();
+        expect(function.apply(input)).andThrow(interruptedException);
+        replay(function);
+
+        assertThrows(Throwable.class, () -> memoizer.compute(input));
+        assertThrows(IllegalArgumentException.class, () -> memoizer.compute(input));
+    }
+
+    @Test
+    public void testDoesNotRecalculateWhenSetToFalse() throws Exception {
+        final Integer input = 1;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function, false);
+        final IllegalArgumentException interruptedException = new IllegalArgumentException();
+        expect(function.apply(input)).andThrow(interruptedException);
+        replay(function);
+
+        assertThrows(Throwable.class, () -> memoizer.compute(input));
+        assertThrows(IllegalArgumentException.class, () -> memoizer.compute(input));
+    }
+
+    @Test
+    public void testDoesRecalculateWhenSetToTrue() throws Exception {
+        final Integer input = 1;
+        final Integer answer = 3;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function, true);
+        final IllegalArgumentException interruptedException = new IllegalArgumentException();
+        expect(function.apply(input)).andThrow(interruptedException).andReturn(answer);
+        replay(function);
+
+        assertThrows(Throwable.class, () -> memoizer.compute(input));
+        assertEquals(answer, memoizer.compute(input));
+    }
+
+    @Test
+    public void testOnlyCallComputableOnceIfDoesNotThrowException() throws Exception {
+        final Integer input = 1;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function);
+        expect(function.apply(input)).andReturn(input);
+        replay(function);
+
+        assertEquals(input, memoizer.compute(input), "Should call computable first time");
+        assertEquals(input, memoizer.compute(input), "Should not call the computable the second time");
+    }
+
+    @Test
+    public void testWhenComputableThrowsError() throws Exception {
+        final Integer input = 1;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function);
+        final Error error = new Error();
+        expect(function.apply(input)).andThrow(error);
+        replay(function);
+
+        assertThrows(Error.class, () -> memoizer.compute(input));
+    }
+
+    @Test
+    public void testWhenComputableThrowsRuntimeException() throws Exception {
+        final Integer input = 1;
+        final Memoizer<Integer, Integer> memoizer = new Memoizer<>(function);
+        final RuntimeException runtimeException = new RuntimeException("Some runtime exception");
+        expect(function.apply(input)).andThrow(runtimeException);
+        replay(function);
+
+        assertThrows(RuntimeException.class, () -> memoizer.compute(input));
+    }
+}