Add failing test for #2461

src/test/java/com/fasterxml/jackson/failing/UnwrappedCaching2461Test.java

@@ -0,0 +1,50 @@
+package com.fasterxml.jackson.failing;
+
+import com.fasterxml.jackson.annotation.JsonUnwrapped;
+import com.fasterxml.jackson.databind.*;
+
+public class UnwrappedCaching2461Test extends BaseMapTest
+{
+    // [databind#2461]
+    static class Base {
+        public String id;
+
+        Base(String id) {
+            this.id = id;
+        }
+    }
+
+    static class BaseContainer {
+        @JsonUnwrapped(prefix = "base.")
+        public Base base;
+
+        BaseContainer(Base base) {
+            this.base = base;
+        }
+    }
+
+    static class BaseContainerContainer {
+        @JsonUnwrapped(prefix = "container.")
+        public BaseContainer container;
+
+        BaseContainerContainer(BaseContainer container) {
+            this.container = container;
+        }
+    }
+
+    // [databind#2461]
+    public void testUnwrappedCaching() throws Exception {
+        final BaseContainer inner = new BaseContainer(new Base("12345"));
+        final BaseContainerContainer outer = new BaseContainerContainer(inner);
+
+        final ObjectMapper mapperOrder1 = newJsonMapper();
+        assertEquals("{\"container.base.id\":\"12345\"}", mapperOrder1.writeValueAsString(outer));
+        assertEquals("{\"base.id\":\"12345\"}", mapperOrder1.writeValueAsString(inner));
+        assertEquals("{\"container.base.id\":\"12345\"}", mapperOrder1.writeValueAsString(outer));
+
+        final ObjectMapper mapperOrder2 = newJsonMapper();
+        assertEquals("{\"base.id\":\"12345\"}", mapperOrder2.writeValueAsString(inner));
+        //  Will fail here
+        assertEquals("{\"container.base.id\":\"12345\"}", mapperOrder2.writeValueAsString(outer));
+    }
+}