Add failing test for #559 (#828)

Author: cowtowncoder

src/test/java/tools/jackson/dataformat/xml/tofix/JaxbXmlValueRecord559Test.java

@@ -0,0 +1,69 @@
+package tools.jackson.dataformat.xml.tofix;
+
+import org.junit.jupiter.api.Test;
+
+import jakarta.xml.bind.annotation.*;
+
+import tools.jackson.databind.AnnotationIntrospector;
+import tools.jackson.databind.introspect.JacksonAnnotationIntrospector;
+import tools.jackson.dataformat.xml.*;
+import tools.jackson.dataformat.xml.testutil.failure.JacksonTestFailureExpected;
+import tools.jackson.module.jakarta.xmlbind.JakartaXmlBindAnnotationIntrospector;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+// [dataformat-xml#559] JAXB @XmlValue deserializing not working with records
+//
+// Root cause: @XmlValue targets only FIELD and METHOD, not PARAMETER.
+// For records, Java doesn't propagate the annotation to the constructor parameter,
+// so Jackson can't match the property-based creator param to the @XmlValue property.
+// Additionally, the JAXB introspector assigns implicit name "value" to @XmlValue
+// properties, causing a property definition split (constructor param keeps "name",
+// while field/getter get renamed to "value").
+public class JaxbXmlValueRecord559Test extends XmlTestUtil
+{
+    @XmlRootElement(name = "TestObject")
+    record TestObject(
+            @XmlValue String name,
+            @XmlAttribute int age) {}
+
+    // POJO equivalent — works fine because field/getter/setter all merge
+    // under the JAXB-assigned "value" name (no constructor param involved)
+    @XmlRootElement(name = "TestObject")
+    static class TestPojo {
+        @XmlValue
+        public String name;
+        @XmlAttribute
+        public int age;
+    }
+
+    private final XmlMapper MAPPER;
+    {
+        JakartaXmlBindAnnotationIntrospector jaxbIntr = new JakartaXmlBindAnnotationIntrospector();
+        AnnotationIntrospector intr = XmlAnnotationIntrospector.Pair.instance(
+                jaxbIntr,
+                new JacksonAnnotationIntrospector());
+        MAPPER = XmlMapper.builder()
+                .annotationIntrospector(intr)
+                .build();
+    }
+
+    // POJO: works
+    @Test
+    public void testDeserializePojo559() throws Exception {
+        String xml = "<TestObject age=\"12\">foo</TestObject>";
+        TestPojo obj = MAPPER.readValue(xml, TestPojo.class);
+        assertEquals("foo", obj.name);
+        assertEquals(12, obj.age);
+    }
+
+    // Record: fails
+    @JacksonTestFailureExpected
+    @Test
+    public void testDeserializeRecord559() throws Exception {
+        String xml = "<TestObject age=\"12\">foo</TestObject>";
+        TestObject obj = MAPPER.readValue(xml, TestObject.class);
+        assertEquals("foo", obj.name());
+        assertEquals(12, obj.age());
+    }
+}