Add a failing test for #2605

src/test/java/com/fasterxml/jackson/failing/EnumPolymorphic2605Test.java

@@ -0,0 +1,45 @@
+package com.fasterxml.jackson.failing;
+
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
+
+import com.fasterxml.jackson.databind.*;
+
+public class EnumPolymorphic2605Test extends BaseMapTest
+{
+    // for [databind#2605]
+    static class EnumContaintingClass <ENUM_TYPE extends Enum<ENUM_TYPE>> {
+        @JsonTypeInfo(
+            use = JsonTypeInfo.Id.CLASS,
+            include = JsonTypeInfo.As.PROPERTY,
+            property = "@class"
+        )
+         private ENUM_TYPE selected;
+
+        protected EnumContaintingClass() { }
+
+        public EnumContaintingClass(ENUM_TYPE selected) {
+          this.selected = selected;
+        }
+
+        public ENUM_TYPE getSelected() {
+          return selected;
+        }
+
+        public void setSelected(ENUM_TYPE selected) {
+          this.selected = selected;
+        }
+    }
+
+    static enum TestEnum { FIRST, SECOND, THIRD; }
+
+    private final ObjectMapper MAPPER = newJsonMapper();
+
+    // for [databind#2605]
+    public void testRoundtrip() throws Exception
+    {
+      EnumContaintingClass<TestEnum> gui = new EnumContaintingClass<TestEnum>(TestEnum.SECOND);
+      String str = MAPPER.writeValueAsString(gui);
+      Object o = MAPPER.readerFor(EnumContaintingClass.class).readValue(str);
+      assertNotNull(o);
+    }
+}