fix(dom): preserve namespaced attribute qualified names

crates/obscura-dom/src/serialize.rs

@@ -99,8 +99,11 @@ impl DomTree {
                         buf.push_str(tag);
                         for attr in attrs {
                             buf.push(' ');
-                            let attr_name = attr.name.local.as_ref();
-                            buf.push_str(attr_name);
+                            if let Some(prefix) = &attr.name.prefix {
+                                buf.push_str(prefix);
+                                buf.push(':');
+                            }
+                            buf.push_str(attr.name.local.as_ref());
                             buf.push_str("=\"");
                             escape_attr(&attr.value, buf);
                             buf.push('"');

crates/obscura-dom/src/tree.rs

@@ -1,4 +1,4 @@
-use html5ever::{LocalName, Namespace, QualName};
+use html5ever::{LocalName, Namespace, Prefix, QualName};
 use std::cell::RefCell;
 use std::collections::HashMap;
 use std::fmt;
@@ -32,13 +32,24 @@ pub struct Attribute {
     pub value: String,
 }
 
-/// The local-name portion of an attribute name, i.e. the part after any prefix.
-/// `"xlink:href"` -> `"href"`, `"href"` -> `"href"`. Used for namespace-aware
-/// attribute lookup, which keys on `(namespace, localName)`.
-fn attr_local_suffix(name: &str) -> &str {
-    match name.rfind(':') {
-        Some(i) => &name[i + 1..],
-        None => name,
+impl Attribute {
+    pub fn qualified_name(&self) -> String {
+        match &self.name.prefix {
+            Some(prefix) => format!("{}:{}", prefix, self.name.local),
+            None => self.name.local.to_string(),
+        }
+    }
+
+    pub fn qualified_name_eq(&self, name: &str) -> bool {
+        match &self.name.prefix {
+            Some(prefix) => {
+                name.len() == prefix.len() + self.name.local.len() + 1
+                    && name.starts_with(prefix.as_ref())
+                    && name.as_bytes().get(prefix.len()) == Some(&b':')
+                    && &name[prefix.len() + 1..] == self.name.local.as_ref()
+            }
+            None => self.name.local.as_ref() == name,
+        }
     }
 }
 
@@ -115,7 +126,7 @@ impl Node {
 
     pub fn get_attribute(&self, name: &str) -> Option<&str> {
         self.attrs()?.iter().find_map(|a| {
-            if a.name.local.as_ref() == name {
+            if a.qualified_name_eq(name) {
                 Some(a.value.as_str())
             } else {
                 None
@@ -136,13 +147,10 @@ impl Node {
         }
     }
 
-    // Read a namespaced attribute by (namespace, localName). The stored local
-    // name may be qualified (e.g. "xlink:href" for setAttributeNS-created attrs)
-    // or a bare local (e.g. "href" for parser-created ones), so compare against
-    // the part after any prefix.
+    // Read a namespaced attribute by (namespace, localName).
     pub fn get_attribute_ns(&self, ns: &str, local: &str) -> Option<&str> {
         self.attrs()?.iter().find_map(|a| {
-            if a.name.ns.as_ref() == ns && attr_local_suffix(a.name.local.as_ref()) == local {
+            if a.name.ns.as_ref() == ns && a.name.local.as_ref() == local {
                 Some(a.value.as_str())
             } else {
                 None
@@ -150,21 +158,24 @@ impl Node {
         })
     }
 
-    // Set a namespaced attribute. `qualified` is the qualified name
-    // (e.g. "xlink:href"); it is stored as the local name with the namespace
-    // recorded, matching how the non-namespaced path stores names, so
-    // getAttribute(qualified) and serialization keep working unchanged.
+    // Set a namespaced attribute using a proper QualName: prefix and local name
+    // remain separate while qualified-name APIs and serialization reconstruct
+    // `prefix:local` when needed.
     pub fn set_attribute_ns(&mut self, ns: &str, qualified: &str, value: String) {
         if let NodeData::Element { attrs, .. } = &mut self.data {
-            let local = attr_local_suffix(qualified);
+            let (prefix, local) = match qualified.split_once(':') {
+                Some((prefix, local)) => (Some(Prefix::from(prefix)), local),
+                None => (None, qualified),
+            };
             if let Some(attr) = attrs
                 .iter_mut()
-                .find(|a| a.name.ns.as_ref() == ns && attr_local_suffix(a.name.local.as_ref()) == local)
+                .find(|a| a.name.ns.as_ref() == ns && a.name.local.as_ref() == local)
             {
+                attr.name.prefix = prefix;
                 attr.value = value;
             } else {
                 attrs.push(Attribute {
-                    name: QualName::new(None, Namespace::from(ns), LocalName::from(qualified)),
+                    name: QualName::new(prefix, Namespace::from(ns), LocalName::from(local)),
                     value,
                 });
             }
@@ -174,7 +185,7 @@ impl Node {
     pub fn remove_attribute_ns(&mut self, ns: &str, local: &str) {
         if let NodeData::Element { attrs, .. } = &mut self.data {
             attrs.retain(|a| {
-                !(a.name.ns.as_ref() == ns && attr_local_suffix(a.name.local.as_ref()) == local)
+                !(a.name.ns.as_ref() == ns && a.name.local.as_ref() == local)
             });
         }
     }

crates/obscura-js/js/bootstrap.js

@@ -1402,7 +1402,12 @@ class Element extends Node {
     if (popoverPrev !== undefined) this._popoverTypeMaybeChanged(popoverPrev);
     if (globalThis.__mutationObservers?.length) globalThis.__notifyMutation('attributes', this._nid, [], [], n);
   }
-  setAttributeNS(ns, n, v) { _dom("set_attribute_ns", this._nid, String(ns == null ? "" : ns) + "\0" + String(n) + "\0" + String(v)); } // n is the qualified name; stored with its namespace
+  setAttributeNS(ns, n, v) {
+    ns = ns == null || ns === '' ? '' : String(ns);
+    n = String(n);
+    _ns_validateQualifiedName(ns, n);
+    _dom("set_attribute_ns", this._nid, ns + "\0" + n + "\0" + String(v));
+  }
   removeAttribute(n) { n = _htmlAttrName(this, n); const popoverPrev = (n === "popover") ? this.popover : undefined; _dom("remove_attribute", this._nid, n); if (popoverPrev !== undefined) this._popoverTypeMaybeChanged(popoverPrev); }
   removeAttributeNS(ns, n) { _dom("remove_attribute_ns", this._nid, String(ns == null ? "" : ns) + "\0" + String(n)); }
   hasAttribute(n) { return this.getAttribute(n) !== null; }
@@ -8423,6 +8428,22 @@ const _ns_isValidXmlName = (name) => {
   return /^[A-Za-z_:][\w.\-:]*$/.test(name);
 };
 
+const _ns_validateQualifiedName = (namespaceURI, qualifiedName) => {
+  const parts = qualifiedName.split(':');
+  if (parts.length > 2 || parts.some((part) => !_ns_isValidXmlName(part))) {
+    throw new DOMException('Invalid attribute name', 'InvalidCharacterError');
+  }
+  const prefix = parts.length === 2 ? parts[0] : null;
+  const XML = 'http://www.w3.org/XML/1998/namespace';
+  const XMLNS = 'http://www.w3.org/2000/xmlns/';
+  if ((prefix && !namespaceURI)
+      || (prefix === 'xml' && namespaceURI !== XML)
+      || ((qualifiedName === 'xmlns' || prefix === 'xmlns') && namespaceURI !== XMLNS)
+      || (namespaceURI === XMLNS && qualifiedName !== 'xmlns' && prefix !== 'xmlns')) {
+    throw new DOMException('The namespace is invalid', 'NamespaceError');
+  }
+};
+
 // Document.prototype.createAttribute: create a detached Attr node
 if (!Document.prototype.createAttribute) {
   Document.prototype.createAttribute = function(localName) {

crates/obscura-js/src/ops.rs

@@ -321,7 +321,7 @@ fn op_dom_inner(state: &OpState, cmd: String, arg1: String, arg2: String) -> Str
             let names: Vec<String> = dom
                 .with_node(NodeId::new(nid), |n| {
                     n.attrs()
-                        .map(|a| a.iter().map(|x| x.name.local.as_ref().to_string()).collect())
+                        .map(|a| a.iter().map(|x| x.qualified_name()).collect())
                         .unwrap_or_default()
                 })
                 .unwrap_or_default();
@@ -373,7 +373,7 @@ fn op_dom_inner(state: &OpState, cmd: String, arg1: String, arg2: String) -> Str
             let nid = arg1.parse::<u32>().unwrap_or(0);
             dom.with_node_mut(NodeId::new(nid), |n| {
                 if let NodeData::Element { attrs, .. } = &mut n.data {
-                    attrs.retain(|a| a.name.local.as_ref() != arg2.as_str());
+                    attrs.retain(|a| !a.qualified_name_eq(&arg2));
                 }
             });
             "true".into()

crates/obscura-js/src/runtime.rs

@@ -1345,6 +1345,40 @@ mod tests {
         assert_eq!(v, serde_json::json!("hi"));
     }
 
+    #[test]
+    fn namespaced_attribute_keeps_its_qualified_name() {
+        let mut rt = setup_runtime("<html><body></body></html>");
+        let v = rt
+            .evaluate("(function(){var s=document.createElementNS('http://www.w3.org/2000/svg','svg');s.setAttributeNS('http://www.w3.org/1999/xlink','xlink:href','#g');return s.getAttribute('xlink:href')+'|'+s.getAttributeNames()[0]+'|'+s.outerHTML;})()")
+            .unwrap();
+        assert_eq!(v, serde_json::json!("#g|xlink:href|<svg xlink:href=\"#g\"></svg>"));
+    }
+
+    #[test]
+    fn parsed_xlink_attribute_is_available_through_both_apis() {
+        let mut rt = setup_runtime(
+            r##"<html><body><svg><use id="u" xlink:href="#icon"></use></svg></body></html>"##,
+        );
+        let v = rt
+            .evaluate("(function(){var u=document.getElementById('u');return u.getAttribute('xlink:href')+'|'+u.getAttributeNS('http://www.w3.org/1999/xlink','href')+'|'+u.getAttributeNames().join(',');})()")
+            .unwrap();
+        assert_eq!(v, serde_json::json!("#icon|#icon|id,xlink:href"));
+    }
+
+    #[test]
+    fn set_attribute_ns_validates_namespace_constraints() {
+        let mut rt = setup_runtime("<html><body></body></html>");
+        let v = rt
+            .evaluate("(function(){var e=document.createElement('div'),out=[];for(const args of [[null,'x:y'],['urn:test','a:b:c'],['urn:test','xml:lang'],['urn:test','xmlns:x']]){try{e.setAttributeNS(args[0],args[1],'v');out.push('none')}catch(err){out.push(err.name)}}return out.join('|');})()")
+            .unwrap();
+        assert_eq!(
+            v,
+            serde_json::json!(
+                "NamespaceError|InvalidCharacterError|NamespaceError|NamespaceError"
+            )
+        );
+    }
+
     #[test]
     fn test_document_title() {
         let mut rt = setup_runtime("<html><head><title>Test</title></head><body></body></html>");