Add test for #3596

src/test/java/tools/jackson/databind/tofix/SealedPolymorphic3596Test.java

@@ -0,0 +1,79 @@
+package tools.jackson.databind.tofix;
+
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
+
+import tools.jackson.databind.ObjectMapper;
+import tools.jackson.databind.testutil.DatabindTestUtil;
+import tools.jackson.databind.testutil.failure.JacksonTestFailureExpected;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+
+// [databind#3596] possibility to not require JsonTypeInfo annotation for sealed classes?
+public class SealedPolymorphic3596Test
+    extends DatabindTestUtil
+{
+
+    @JsonTypeInfo(use = JsonTypeInfo.Id.SIMPLE_NAME)
+    static sealed class SealedSuperWithAnno3596
+            permits SealedSubWithAnno3596A, SealedSubWithAnno3596B {
+    }
+
+    static sealed class SealedSuperWithoutAnno3596
+            permits SealedSubWithoutAnno3596A, SealedSubWithoutAnno3596B {
+    }
+
+    private final ObjectMapper MAPPER = newJsonMapper();
+
+    // Same as [databind#4601], but just so we have something to compare with
+    @Test
+    public void testSealedClassWithAnnotation()
+            throws Exception
+    {
+        String jsonStr = a2q(String.format("{'@type':'%s'}", SealedSubWithAnno3596A.class.getSimpleName()));
+
+        // ser
+        assertEquals(jsonStr, MAPPER.writeValueAsString(new SealedSubWithAnno3596A()));
+
+        // deser
+        SealedSuperWithAnno3596 bean = MAPPER.readValue(jsonStr, SealedSuperWithAnno3596.class);
+        assertInstanceOf(SealedSuperWithAnno3596.class, bean);
+        assertInstanceOf(SealedSubWithAnno3596A.class, bean);
+    }
+
+    // Without annotation
+    @JacksonTestFailureExpected
+    @Test
+    public void testSealedClassWithoutAnnotation()
+            throws Exception
+    {
+        String jsonStr = a2q(String.format("{'@type':'%s'}", SealedSubWithoutAnno3596A.class.getSimpleName()));
+
+        // ser
+        assertEquals(jsonStr, MAPPER.writeValueAsString(new SealedSubWithoutAnno3596A()));
+
+        // deser
+        SealedSuperWithoutAnno3596 bean = MAPPER.readValue(jsonStr, SealedSuperWithoutAnno3596.class);
+        assertInstanceOf(SealedSuperWithoutAnno3596.class, bean);
+        assertInstanceOf(SealedSubWithoutAnno3596A.class, bean);
+    }
+
+}
+
+final class SealedSubWithAnno3596A
+        extends SealedPolymorphic3596Test.SealedSuperWithAnno3596 {
+}
+
+final class SealedSubWithAnno3596B
+        extends SealedPolymorphic3596Test.SealedSuperWithAnno3596 {
+}
+
+final class SealedSubWithoutAnno3596A
+        extends SealedPolymorphic3596Test.SealedSuperWithoutAnno3596 {
+}
+
+final class SealedSubWithoutAnno3596B
+        extends SealedPolymorphic3596Test.SealedSuperWithoutAnno3596 {
+}