more testing

Author: cowtowncoder

src/test/java/tools/jackson/dataformat/xml/ser/XmlGeneratorInitializerTest.java

@@ -5,6 +5,7 @@
 import tools.jackson.databind.ObjectWriter;
 import tools.jackson.dataformat.xml.XmlMapper;
 import tools.jackson.dataformat.xml.XmlTestUtil;
+import tools.jackson.dataformat.xml.XmlWriteFeature;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.fail;
@@ -13,7 +14,7 @@ public class XmlGeneratorInitializerTest extends XmlTestUtil
 {
     private final XmlMapper MAPPER = newMapper();
 
-    // [dataformat-xml#150]: DTD writing
+    // [dataformat-xml#150]: DTD writing -- ok cases
     @Test
     public void testDTDWithOnlyRootElement() throws Exception
     {
@@ -59,6 +60,25 @@ public void testDTDWithInternalSubset() throws Exception
                 w.writeValueAsString(new StringBean("test")));
     }
 
+    // Verify prolog ordering: XML declaration must come before DOCTYPE
+    @Test
+    public void testDTDWithXmlDeclaration() throws Exception
+    {
+        XmlMapper mapper = XmlMapper.builder()
+                .configure(XmlWriteFeature.WRITE_XML_DECLARATION, true)
+                .build();
+        ObjectWriter w = mapper.writer().with(
+                new XmlGeneratorInitializer()
+                        .setDTD("StringBean", "system", "http://foo.bar", null));
+        // XML declaration is emitted with single quotes, DOCTYPE with double quotes,
+        // so cannot use a2q() on the whole string here.
+        assertEquals("<?xml version='1.0' encoding='UTF-8'?>"
+                +"<!DOCTYPE StringBean PUBLIC \"http://foo.bar\" \"system\">"
+                +"<StringBean><text>test</text></StringBean>",
+                w.writeValueAsString(new StringBean("test")));
+    }
+
+    // [dataformat-xml#150]: DTD writing -- failing cases
     @Test
     public void testDTDInvalidNoRoot() throws Exception
     {