Backport test for #3220 in 2.11; actually passes (despite being under failing) for 2.11.4.

Author: cowtowncoder

src/test/java/com/fasterxml/jackson/failing/MixinForFactoryMethod3220Test.java

@@ -0,0 +1,147 @@
+package com.fasterxml.jackson.failing;
+
+import java.util.Objects;
+
+import com.fasterxml.jackson.annotation.*;
+
+import com.fasterxml.jackson.databind.BaseMapTest;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+
+public class MixinForFactoryMethod3220Test
+    extends BaseMapTest
+{
+    // [databind#3220]
+    static class Timestamped<T> {
+        private final T value;
+        private final int timestamp;
+
+        Timestamped(T value, int timestamp) {
+            this.value = value;
+            this.timestamp = timestamp;
+        }
+
+        public static <T> Timestamped<T> stamp(T value, int timestamp) {
+            return new Timestamped<>(value, timestamp);
+        }
+
+        public T getValue() {
+            return value;
+        }
+
+        public int getTimestamp() {
+            return timestamp;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            Timestamped<?> that = (Timestamped<?>) o;
+            return timestamp == that.timestamp && Objects.equals(value, that.value);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(value, timestamp);
+        }
+    }
+
+    abstract static class TimestampedMixin<T> {
+        @JsonCreator
+        public static <T> void stamp(
+            @JsonProperty("value") T value,
+            @JsonProperty("timestamp") int timestamp) {
+        }
+
+        @JsonGetter("value")
+        abstract T getValue();
+
+        @JsonGetter("timestamp")
+        abstract int getTimestamp();
+    }
+
+    static class Profile {
+        private final String firstName;
+        private final String lastName;
+
+        @JsonCreator
+        public Profile(@JsonProperty("firstName") String firstName,
+            @JsonProperty("lastName") String lastName
+        ) {
+            this.firstName = firstName;
+            this.lastName = lastName;
+        }
+
+        @JsonGetter("firstName")
+        public String getFirstName() {
+            return firstName;
+        }
+
+        @JsonGetter("lastName")
+        public String getLastName() {
+            return lastName;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            Profile profile = (Profile) o;
+            return Objects.equals(firstName, profile.firstName) && Objects.equals(lastName, profile.lastName);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(firstName, lastName);
+        }
+    }
+
+    static class User {
+        private final Timestamped<Profile> profile;
+
+        @JsonCreator
+        User(@JsonProperty("profile") Timestamped<Profile> profile) {
+            this.profile = profile;
+        }
+
+        @JsonGetter("profile")
+        public Timestamped<Profile> getProfile() {
+            return profile;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            User user = (User) o;
+            return Objects.equals(profile, user.profile);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(profile);
+        }
+    }
+
+    // [databind#3220]
+    public void testMixin() throws Exception
+    {
+        ObjectMapper mapper = JsonMapper.builder()
+                .addMixIn(Timestamped.class, TimestampedMixin.class)
+                .build();
+
+        Profile profile = new Profile("Jackson", "Databind");
+        User user = new User(new Timestamped<>(profile, 1));
+
+        User deserializedUser = mapper.readValue(
+            mapper.writerFor(User.class).writeValueAsString(user),
+            User.class
+        );
+
+        Timestamped<Profile> td = deserializedUser.getProfile();
+        Profile deserializedProfile = td.getValue();
+        assertEquals(profile, deserializedProfile);
+        assertEquals(user, deserializedUser);
+    }
+}