Test for #4792, new regression b/w 2.17 and 2.18 (#4793)

Author: JooHyukKim

src/test/java/com/fasterxml/jackson/databind/tofix/PolymorphicDeserWithJsonUnwrapped4792Test.java

@@ -0,0 +1,59 @@
+package com.fasterxml.jackson.databind.tofix;
+
+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 com.fasterxml.jackson.databind.testutil.failure.JacksonTestFailureExpected;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+
+import static com.fasterxml.jackson.annotation.JsonProperty.Access.READ_ONLY;
+
+// [databind#4792] JsonUnwrapped throwing "Unrecognized field" after upgrade to 2.18
+public class PolymorphicDeserWithJsonUnwrapped4792Test
+    extends DatabindTestUtil
+{
+
+    @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "name")
+    @JsonSubTypes({
+            @JsonSubTypes.Type(value = SubA.class, name = "A"),
+    })
+    interface Parent { }
+
+    static class SubA implements Parent {
+        @JsonUnwrapped
+        @JsonProperty(access = READ_ONLY)
+        private Model model;
+
+        @JsonCreator
+        public SubA(@JsonProperty("model") Model model) {
+            this.model = model;
+        }
+    }
+
+    static class Model {
+        public String name;
+    }
+
+    public static class Wrapper {
+        public Parent model;
+    }
+
+    private final ObjectMapper objectMapper = newJsonMapper();
+
+    @JacksonTestFailureExpected
+    @Test
+    public void testMainTest()
+            throws Exception
+    {
+        Wrapper w = objectMapper.readValue(a2q("{'model':{'name':'A','name': 'Rick'}}"), Wrapper.class);
+
+        assertInstanceOf(SubA.class, w.model);
+        assertInstanceOf(Model.class, ((SubA) w.model).model);
+        assertEquals("Rick", ((SubA) w.model).model.name);
+    }
+
+}