1 files changed, 155 insertions, 0 deletions
diff --git a/src/test/java/org/apache/commons/lang3/tuple/MutablePairTest.java b/src/test/java/org/apache/commons/lang3/tuple/MutablePairTest.java
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+++ b/src/test/java/org/apache/commons/lang3/tuple/MutablePairTest.java
@@ -0,0 +1,155 @@
+/*
+ * 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.tuple;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.HashMap;
+import java.util.Map.Entry;
+
+import org.apache.commons.lang3.AbstractLangTest;
+import org.apache.commons.lang3.SerializationUtils;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test the MutablePair class.
+ */
+public class MutablePairTest extends AbstractLangTest {
+
+    @Test
+    public void testBasic() {
+        MutablePair<Integer, String> oldPair = new MutablePair<>(0, "foo");
+        MutablePair<Integer, String> nowPair;
+        for (int i=0; i<4; i++) {
+            nowPair = MutablePair.of(oldPair);
+            assertEquals(0, nowPair.left.intValue());
+            assertEquals(0, nowPair.getLeft().intValue());
+            assertEquals("foo", nowPair.right);
+            assertEquals("foo", nowPair.getRight());
+            assertEquals(oldPair, nowPair);
+            oldPair = nowPair;
+        }
+
+        MutablePair<Object, String> oldPair2 = new MutablePair<>(null, "bar");
+        MutablePair<Object, String> nowPair2;
+        for (int i=0; i<4; i++) {
+            nowPair2 = MutablePair.of(oldPair2);
+            assertNull(nowPair2.left);
+            assertNull(nowPair2.getLeft());
+            assertEquals("bar", nowPair2.right);
+            assertEquals("bar", nowPair2.getRight());
+            oldPair2 = nowPair2;
+        }
+    }
+
+    @Test
+    public void testDefault() {
+        final MutablePair<Integer, String> pair = new MutablePair<>();
+        assertNull(pair.getLeft());
+        assertNull(pair.getRight());
+    }
+
+    @Test
+    public void testEmptyArrayGenerics() {
+        final MutablePair<Integer, String>[] empty = MutablePair.emptyArray();
+        assertEquals(0, empty.length);
+    }
+
+    @Test
+    public void testEmptyArrayLength() {
+        @SuppressWarnings("unchecked")
+        final MutablePair<Integer, String>[] empty = (MutablePair<Integer, String>[]) MutablePair.EMPTY_ARRAY;
+        assertEquals(0, empty.length);
+    }
+
+    @Test
+    public void testEquals() {
+        assertEquals(MutablePair.of(null, "foo"), MutablePair.of(null, "foo"));
+        assertNotEquals(MutablePair.of("foo", 0), MutablePair.of("foo", null));
+        assertNotEquals(MutablePair.of("foo", "bar"), MutablePair.of("xyz", "bar"));
+
+        final MutablePair<String, String> p = MutablePair.of("foo", "bar");
+        assertEquals(p, p);
+        assertNotEquals(p, new Object());
+    }
+
+    @Test
+    public void testHashCode() {
+        assertEquals(MutablePair.of(null, "foo").hashCode(), MutablePair.of(null, "foo").hashCode());
+    }
+
+    @Test
+    public void testMutate() {
+        final MutablePair<Integer, String> pair = new MutablePair<>(0, "foo");
+        pair.setLeft(42);
+        pair.setRight("bar");
+        assertEquals(42, pair.getLeft().intValue());
+        assertEquals("bar", pair.getRight());
+    }
+
+    @Test
+    public void testOfNonNull() {
+        assertThrows(NullPointerException.class, () -> MutablePair.ofNonNull(null, null));
+        assertThrows(NullPointerException.class, () -> MutablePair.ofNonNull(null, "x"));
+        assertThrows(NullPointerException.class, () -> MutablePair.ofNonNull("x", null));
+        final MutablePair<String, String> pair = MutablePair.ofNonNull("x", "y");
+        assertEquals("x", pair.left);
+        assertEquals("y", pair.right);
+    }
+
+    @Test
+    public void testPairOfMapEntry() {
+        final HashMap<Integer, String> map = new HashMap<>();
+        map.put(0, "foo");
+        final Entry<Integer, String> entry = map.entrySet().iterator().next();
+        final Pair<Integer, String> pair = MutablePair.of(entry);
+        assertEquals(entry.getKey(), pair.getLeft());
+        assertEquals(entry.getValue(), pair.getRight());
+    }
+
+    @Test
+    public void testPairOfObjects() {
+        final MutablePair<Integer, String> pair = MutablePair.of(0, "foo");
+        assertEquals(0, pair.getLeft().intValue());
+        assertEquals("foo", pair.getRight());
+        final MutablePair<Object, String> pair2 = MutablePair.of(null, "bar");
+        assertNull(pair2.getLeft());
+        assertEquals("bar", pair2.getRight());
+        final MutablePair<?, ?> pair3 = MutablePair.of(null, null);
+        assertNull(pair3.left);
+        assertNull(pair3.right);
+    }
+
+    @Test
+    public void testSerialization() throws Exception {
+        final MutablePair<Integer, String> origPair = MutablePair.of(0, "foo");
+        final MutablePair<Integer, String> deserializedPair = SerializationUtils.roundtrip(origPair);
+        assertEquals(origPair, deserializedPair);
+        assertEquals(origPair.hashCode(), deserializedPair.hashCode());
+    }
+
+    @Test
+    public void testToString() {
+        assertEquals("(null,null)", MutablePair.of(null, null).toString());
+        assertEquals("(null,two)", MutablePair.of(null, "two").toString());
+        assertEquals("(one,null)", MutablePair.of("one", null).toString());
+        assertEquals("(one,two)", MutablePair.of("one", "two").toString());
+    }
+}