test: add unit test for ToStringUtils

dubbo-common/src/test/java/org/apache/dubbo/common/utils/ToStringUtilsTest.java

@@ -0,0 +1,80 @@
+/*
+ * 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.dubbo.common.utils;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class ToStringUtilsTest {
+
+    @Test
+    void testPrintToString() {
+        // Testing the first method that tries to use JSON
+        String result = ToStringUtils.printToString("Dubbo");
+        // It should wrap it in quotes because of JsonUtils
+        assertTrue(result.contains("Dubbo"));
+
+        assertEquals("null", ToStringUtils.printToString(null));
+    }
+
+    @Test
+    void testToStringWithSimpleTypes() {
+        // Simple types should just return their string value
+        assertEquals("123", ToStringUtils.toString(123));
+        assertEquals("true", ToStringUtils.toString(true));
+        assertEquals("null", ToStringUtils.toString(null));
+    }
+
+    @Test
+    void testToStringWithArray() {
+        // Testing the loop that builds [item1, item2]
+        Object[] array = new Object[] {"A", "B", 1};
+        assertEquals("[A, B, 1]", ToStringUtils.toString(array));
+    }
+
+    @Test
+    void testToStringWithList() {
+        // Testing the List block
+        List<String> list = Arrays.asList("Apple", "Banana");
+        assertEquals("[Apple, Banana]", ToStringUtils.toString(list));
+    }
+
+    @Test
+    void testToStringWithMap() {
+        // Testing the Map block with the key=value format
+        Map<String, Integer> map = new HashMap<>();
+        map.put("key", 1);
+        assertEquals("{key=1}", ToStringUtils.toString(map));
+    }
+
+    @Test
+    void testComplexRecursion() {
+        // A List inside a Map
+        Map<String, Object> complexMap = new HashMap<>();
+        complexMap.put("list", Arrays.asList(1, 2));
+
+        String result = ToStringUtils.toString(complexMap);
+        assertEquals("{list=[1, 2]}", result);
+    }
+}