Fix #578 (@JsonAppend properties serialized twice) (#590)

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -4,6 +4,11 @@ Project: jackson-dataformat-xml
 === Releases ===
 ------------------------------------------------------------------------
 
+Not yet released
+
+#578: `XmlMapper` serializes `@JsonAppend` property twice
+ (reported by @stepince)
+
 2.15.0-rc2 (28-Mar-2023)
 
 #286: Conflict between `@JsonIdentityInfo` and Unwrapped Lists

src/main/java/com/fasterxml/jackson/dataformat/xml/JacksonXmlAnnotationIntrospector.java

@@ -1,12 +1,14 @@
 package com.fasterxml.jackson.dataformat.xml;
 
 import java.lang.annotation.Annotation;
+import java.util.List;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.PropertyName;
 import com.fasterxml.jackson.databind.cfg.MapperConfig;
 import com.fasterxml.jackson.databind.introspect.*;
 import com.fasterxml.jackson.databind.jsontype.impl.StdTypeResolverBuilder;
+import com.fasterxml.jackson.databind.ser.BeanPropertyWriter;
 import com.fasterxml.jackson.dataformat.xml.annotation.*;
 
 /**
@@ -124,6 +126,19 @@ public String findNamespace(MapperConfig<?> config, Annotated ann)
         return null;
     }
 
+    /**
+     * Due to issue [dataformat-xml#578] need to suppress calls to this method
+     * to avoid duplicate virtual properties from being added. Not elegant
+     * but .. works.
+     *
+     * @since 2.15
+     */
+    @Override
+    public void findAndAddVirtualProperties(MapperConfig<?> config, AnnotatedClass ac,
+            List<BeanPropertyWriter> properties) {
+        return;
+    }
+
     /*
     /**********************************************************************
     /* XmlAnnotationIntrospector, isXxx methods

src/test/java/com/fasterxml/jackson/dataformat/xml/failing/JsonAppend578Test.java renamed to src/test/java/com/fasterxml/jackson/dataformat/xml/ser/JsonAppend578Test.java

@@ -1,4 +1,4 @@
-package com.fasterxml.jackson.dataformat.xml.failing;
+package com.fasterxml.jackson.dataformat.xml.ser;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.databind.*;
@@ -53,6 +53,6 @@ public VirtualBeanPropertyWriter withConfig(MapperConfig<?> config, AnnotatedCla
     // [dataformat-xml#578]: Duplication of virtual properties
     public void testJsonAppend() throws Exception {
         String xml = MAPPER.writeValueAsString(new Pojo578("foo"));
-        assertEquals("<Pojo><name>foo</name><virtual>bar</virtual></Pojo>",xml);
+        assertEquals("<Pojo578><name>foo</name><virtual>bar</virtual></Pojo578>",xml);
     }
 }