Add failing test for #2021

Author: cowtowncoder

src/test/java/com/fasterxml/jackson/databind/deser/creators/DelegatingCreatorAnnotations2016Test.java

@@ -3,6 +3,7 @@
 import java.util.*;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+
 import com.fasterxml.jackson.databind.BaseMapTest;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;

src/test/java/com/fasterxml/jackson/failing/DelegatingCreatorAnnotations2021Test.java

@@ -0,0 +1,58 @@
+package com.fasterxml.jackson.failing;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+
+import com.fasterxml.jackson.core.JsonParser;
+
+import com.fasterxml.jackson.databind.BaseMapTest;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
+
+// Tests for problems uncovered with [databind#2016]; related to
+// `@JsonDeserialize` modifications to type, deserializer(s)
+@SuppressWarnings("serial")
+public class DelegatingCreatorAnnotations2021Test extends BaseMapTest
+{
+    // [databind#2021]
+    static class DelegatingWithCustomDeser2021 {
+        public final static Double DEFAULT = 0.25;
+
+        Number value;
+
+        @JsonCreator(mode = JsonCreator.Mode.DELEGATING)
+        public DelegatingWithCustomDeser2021(@JsonDeserialize(using = ValueDeser2021.class) Number v) {
+            value = v;
+        }
+    }
+
+    static class ValueDeser2021 extends StdDeserializer<Number> {
+        public ValueDeser2021() { super(Number.class); }
+
+        @Override
+        public Number deserialize(JsonParser p, DeserializationContext ctxt)
+            throws IOException
+        {
+            p.skipChildren();
+            return DelegatingWithCustomDeser2021.DEFAULT;
+        }
+    }
+
+    /*
+    /**********************************************************************
+    /* Test methods
+    /**********************************************************************
+     */
+
+    private final ObjectMapper MAPPER = newObjectMapper();
+
+    // [databind#2021]
+    public void testCustomDeserForDelegating() throws Exception
+    {
+        DelegatingWithCustomDeser2021 actual = MAPPER.readValue(" true ", DelegatingWithCustomDeser2021.class);
+        assertEquals(DelegatingWithCustomDeser2021.DEFAULT, actual.value);
+    }
+}