avm2+tests: Fully implement XML.appendChild, add a test

core/src/avm2/globals/xml.rs

@@ -314,22 +314,59 @@ pub fn append_child<'gc>(
 ) -> Result<Value<'gc>, Error<'gc>> {
     let xml = this.as_xml_object().unwrap();
 
-    let child = args.get_object(activation, 0, "child")?;
-    if let Some(child) = child.as_xml_object() {
+    let child = args.get_value(0);
+    if let Some(child) = child.as_object().and_then(|o| o.as_xml_object()) {
         xml.node()
             .append_child(activation.context.gc_context, *child.node())?;
-    } else if let Some(list) = child.as_xml_list_object() {
-        if list.target().is_some() {
-            return Err("Cannot append XMLList with target".into());
-        }
+    } else if let Some(list) = child.as_object().and_then(|o| o.as_xml_list_object()) {
         for child in &*list.children() {
             xml.node()
                 .append_child(activation.context.gc_context, *child.node())?;
         }
     } else {
-        return Err(format!("Cannot append non-XML value {child:?}").into());
+        // Appending a non-XML/XMLList object
+        let last_child_name = if let E4XNodeKind::Element { children, .. } = &*xml.node().kind() {
+            let num_children = children.len();
+
+            match num_children {
+                0 => None,
+                _ => children[num_children - 1].local_name(),
+            }
+        } else {
+            // FIXME - figure out exactly when appending is allowed in FP,
+            // and throw the proper AVM error.
+            return Err(Error::RustError(
+                format!(
+                    "Cannot append child {child:?} to node {:?}",
+                    xml.node().kind()
+                )
+                .into(),
+            ));
         };
-    Ok(Value::Undefined)
+
+        let text = child.coerce_to_string(activation)?;
+        if let Some(last_child_name) = last_child_name {
+            let element_node =
+                E4XNode::element(activation.context.gc_context, last_child_name, *xml.node()); // Creating an element requires passing a parent node, unlike creating a text node
+
+            let text_node = E4XNode::text(activation.context.gc_context, text, None);
+
+            element_node
+                .append_child(activation.context.gc_context, text_node)
+                .expect("Appending to an element node should succeed");
+
+            xml.node()
+                .append_child(activation.context.gc_context, element_node)?;
+        } else {
+            let node = E4XNode::text(activation.context.gc_context, text, None);
+            // The text node will be parented in the append_child operation
+
+            xml.node()
+                .append_child(activation.context.gc_context, node)?;
+        }
+    };
+
+    Ok(this.into())
 }
 
 pub fn descendants<'gc>(

tests/tests/swfs/avm2/xml_appendchild/Test.as

@@ -0,0 +1,27 @@
+package {
+    import flash.display.MovieClip;
+
+    public class Test extends MovieClip {
+
+        public function Test() {
+            XML.prettyPrinting = false;
+            var xml:XML = <a><child1/><child2/></a>;
+            trace(xml);
+            var xmls:XMLList = (<root><child3/><child4/></root>).children();
+            var appended:XML = xml.appendChild(xmls);
+            trace(appended);
+            trace(xml);
+            trace(xml == appended);
+            xml.child3 = "4";
+            trace(xmls);
+            xml.appendChild("qwerty");
+            trace(xml);
+            trace(xml.appendChild({"key":"value"}));
+            var xml2:XML = <b>abcd</b>;
+            trace(xml2.appendChild("text1").toXMLString());
+            xml2 = <b></b>;
+            trace(xml2.appendChild("text2").toXMLString());
+        }
+    }
+}
+

tests/tests/swfs/avm2/xml_appendchild/output.txt

@@ -0,0 +1,10 @@
+<a><child1/><child2/></a>
+<a><child1/><child2/><child3/><child4/></a>
+<a><child1/><child2/><child3/><child4/></a>
+true
+<child3>4</child3>
+<child4/>
+<a><child1/><child2/><child3>4</child3><child4/><child4>qwerty</child4></a>
+<a><child1/><child2/><child3>4</child3><child4/><child4>qwerty</child4><child4>[object Object]</child4></a>
+<b>abcdtext1</b>
+<b>text2</b>

tests/tests/swfs/avm2/xml_appendchild/test.toml

@@ -0,0 +1 @@
+num_frames = 1