Add a new test for JsonNodeFactory

Author: cowtowncoder

src/test/java/com/fasterxml/jackson/databind/node/JsonNodeFactoryTest.java

@@ -2,13 +2,24 @@
 
 import java.math.BigDecimal;
 import java.math.BigInteger;
+import java.util.TreeMap;
 
 import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.json.JsonMapper;
 
 public class JsonNodeFactoryTest extends NodeTestBase
 {
     private final ObjectMapper MAPPER = objectMapper();
 
+    static class SortingNodeFactory extends JsonNodeFactory {
+        private static final long serialVersionUID = 1L;
+
+        @Override
+        public ObjectNode objectNode() {
+            return new ObjectNode(this, new TreeMap<String, JsonNode>());
+        }
+    }
+
     public void testSimpleCreation()
     {
         JsonNodeFactory f = MAPPER.getNodeFactory();
@@ -36,4 +47,29 @@ public void testSimpleCreation()
 
         assertTrue(f.missingNode().isMissingNode());
     }
+
+    // 09-Sep-2020, tatu: Let's try something more useful: auto-sorting
+    //    Tree Model!
+
+   public void testSortingObjectNode() throws Exception
+   {
+       final String SIMPLE_INPUT = "{\"b\":2,\"a\":1}";
+       
+       // First, by default, ordering retained:
+       assertEquals(SIMPLE_INPUT,
+               MAPPER.writeValueAsString(MAPPER.readTree(SIMPLE_INPUT)));
+
+       // But can change easily
+       ObjectMapper mapper = JsonMapper.builder()
+               .nodeFactory(new SortingNodeFactory())
+               .build();
+       JsonNode sort = mapper.readTree(SIMPLE_INPUT);
+       assertEquals("{\"a\":1,\"b\":2}", MAPPER.writeValueAsString(sort));
+
+       final String BIGGER_INPUT = a2q("['x',{'b':1,'c':true,'a':3},false]");
+       final String BIGGER_OUTPUT = a2q("['x',{'a':3,'b':1,'c':true},false]");
+
+       assertEquals(BIGGER_OUTPUT,
+               MAPPER.writeValueAsString(mapper.readTree(BIGGER_INPUT)));
+   }
 }