Polymorphic Deduction Tests for Object vs Array (#4791)

Tests for #4772, mark as fixed (actually fix via FasterXML/jackson-core#1356 for 2.19.0)

Author: Gems

release-notes/CREDITS-2.x

@@ -1828,6 +1828,9 @@ Eduard Gomoliako (@Gems)
  * Reported #4602: Possible wrong use of _arrayDelegateDeserializer in
    BeanDeserializerBase::deserializeFromObjectUsingNonDefault()
   (2.18.0)
+ * Reported #4772: Serialization and deserialization issue of sub-types used with
+  `JsonTypeInfo.Id.DEDUCTION` where sub-types are Object and Array
+  (2.19.0)
 
 Mathijs Vogelzang (@mathijs81)
  * Reported #4678: Java records don't serialize with `MapperFeature.REQUIRE_SETTERS_FOR_GETTERS`

release-notes/VERSION-2.x

@@ -24,6 +24,9 @@ Project: jackson-databind
   Map object is ignored when Map key type not defined
  (reported by @devdanylo)
  (fix by Joo-Hyuk K)
+#4772: Serialization and deserialization issue of sub-types used with
+  `JsonTypeInfo.Id.DEDUCTION` where sub-types are Object and Array
+ (reported by Eduard G)
 #4773: `SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS` should not apply to Maps
   with uncomparable keys
  (requested by @nathanukey)

src/test/java/com/fasterxml/jackson/databind/jsontype/PolymorphicDeductionObjectVsArrayTest.java

@@ -0,0 +1,108 @@
+package com.fasterxml.jackson.databind.jsontype;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
+
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.annotation.*;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.testutil.DatabindTestUtil;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class PolymorphicDeductionObjectVsArrayTest extends DatabindTestUtil {
+    @JsonTypeInfo(use = JsonTypeInfo.Id.DEDUCTION, defaultImpl = DataArray.class)
+    @JsonSubTypes({@JsonSubTypes.Type(DataObject.class), @JsonSubTypes.Type(DataArray.class)})
+    interface Data {
+        @JsonIgnore
+        boolean isObject();
+    }
+
+    static class DataItem {
+        final String id;
+
+        @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
+        DataItem(@JsonProperty("id") String id) {
+            this.id = id;
+        }
+
+        public String getId() {
+            return id;
+        }
+    }
+
+    static class DataObject extends DataItem implements Data {
+
+        @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
+        DataObject(@JsonProperty("id") String id) {
+            super(id);
+        }
+
+        @Override
+        public boolean isObject() {
+            return true;
+        }
+    }
+
+    static class DataArray extends ArrayList<DataItem> implements Data {
+        private static final long serialVersionUID = 1L;
+
+        @JsonCreator
+        DataArray(Collection<DataItem> items) {
+            super(new ArrayList<>(items));
+        }
+
+        @Override
+        public boolean isObject() {
+            return false;
+        }
+    }
+
+    static class Container {
+        @JsonProperty("data")
+        Data data;
+    }
+
+    private final ObjectMapper MAPPER = newJsonMapper();
+
+    private static final String containerWithObjectData = a2q("{'data':{'id':'#1'}}");
+
+    private static final String containerWithArrayData = a2q("{'data':[{'id':'#1'}]}");
+
+    @Test
+    public void testDeserialization() throws Exception {
+        Container container = MAPPER.readValue(containerWithObjectData, Container.class);
+
+        assertInstanceOf(DataObject.class, container.data);
+        assertSame(container.data.getClass(), DataObject.class);
+        assertTrue(container.data.isObject());
+        assertEquals("#1", ((DataItem) container.data).id);
+
+        container = MAPPER.readValue(containerWithArrayData, Container.class);
+        assertInstanceOf(DataArray.class, container.data);
+        assertEquals(container.data.getClass(), DataArray.class);
+        assertFalse(container.data.isObject());
+
+        @SuppressWarnings("unchecked")
+        Iterator<DataItem> arrayDataIterator = ((Iterable<DataItem>) container.data).iterator();
+
+        assertTrue(arrayDataIterator.hasNext());
+        assertEquals("#1", arrayDataIterator.next().id);
+    }
+
+    @Test
+    public void testSerialization() throws Exception {
+        Container container = new Container();
+        container.data = new DataObject("#1");
+        String json = MAPPER.writeValueAsString(container);
+        assertEquals(containerWithObjectData, json);
+
+        container = new Container();
+        container.data = new DataArray(Arrays.asList(new DataItem("#1")));
+        json = MAPPER.writeValueAsString(container);
+        assertEquals(containerWithArrayData, json);
+    }
+}

src/test/java/com/fasterxml/jackson/databind/jsontype/TestGenericListSerialization.java

@@ -10,7 +10,6 @@
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.testutil.DatabindTestUtil;
-import com.fasterxml.jackson.databind.type.TypeFactory;
 
 import static org.junit.jupiter.api.Assertions.*;
 

src/test/java/com/fasterxml/jackson/databind/jsontype/TestPolymorphicDeduction.java

@@ -9,15 +9,11 @@
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonValue;
 
-import com.fasterxml.jackson.databind.DeserializationFeature;
-import com.fasterxml.jackson.databind.JavaType;
-import com.fasterxml.jackson.databind.MapperFeature;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.exc.InvalidDefinitionException;
 import com.fasterxml.jackson.databind.exc.InvalidTypeIdException;
 import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.databind.testutil.DatabindTestUtil;
-import com.fasterxml.jackson.databind.type.TypeFactory;
 
 import static org.junit.jupiter.api.Assertions.*;
 

src/test/java/com/fasterxml/jackson/databind/jsontype/TestTypeNames.java

@@ -12,7 +12,6 @@
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsontype.impl.StdSubtypeResolver;
 import com.fasterxml.jackson.databind.testutil.DatabindTestUtil;
-import com.fasterxml.jackson.databind.type.TypeFactory;
 
 import static org.junit.jupiter.api.Assertions.*;
 

src/test/java/com/fasterxml/jackson/databind/jsontype/TestTypedDeserialization.java

@@ -14,7 +14,6 @@
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.testutil.DatabindTestUtil;
-import com.fasterxml.jackson.databind.type.TypeFactory;
 
 import static org.junit.jupiter.api.Assertions.*;