diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 19901c43796..f331eb26a07 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -1028,17 +1028,11 @@ trait PrivateDocumentHelpers {
 impl<'a> PrivateDocumentHelpers for JSRef<'a, Document> {
     fn create_node_list<F: Fn(JSRef<Node>) -> bool>(self, callback: F) -> Temporary<NodeList> {
         let window = self.window.root();
-        let document_element = self.GetDocumentElement().root();
-        let mut nodes = RootedVec::new();
-        if let Some(ref root) = document_element {
-            for node in NodeCast::from_ref(root.r()).traverse_preorder() {
-                let node = node.root();
-                if callback(node.r()) {
-                    nodes.push(JS::from_rooted(node.r()));
-                }
-            }
-        };
-        NodeList::new_simple_list(window.r(), &nodes)
+        let doc = self.GetDocumentElement().root();
+        let maybe_node = doc.r().map(NodeCast::from_ref);
+        let iter = maybe_node.iter().flat_map(|node| node.traverse_preorder())
+                             .filter(|node| callback(node.root().r()));
+        NodeList::new_simple_list(window.r(), iter)
     }
 
     fn get_html_element(self) -> Option<Temporary<HTMLHtmlElement>> {
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index f7401c99b11..72e385cdfac 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -913,12 +913,9 @@ impl<'a> NodeHelpers for JSRef<'a, Node> {
     // https://dom.spec.whatwg.org/#dom-parentnode-queryselectorall
     #[allow(unsafe_code)]
     fn query_selector_all(self, selectors: DOMString) -> Fallible<Temporary<NodeList>> {
-        let mut nodes = RootedVec::new();
-        for node in try!(unsafe { self.query_selector_iter(selectors) }) {
-            nodes.push(JS::from_rooted(node));
-        }
         let window = window_from_node(self).root();
-        Ok(NodeList::new_simple_list(window.r(), &nodes))
+        let iter = try!(unsafe { self.query_selector_iter(selectors) });
+        Ok(NodeList::new_simple_list(window.r(), iter))
     }
 
 
diff --git a/components/script/dom/nodelist.rs b/components/script/dom/nodelist.rs
index 66b2cb6c5c4..bb3df75e920 100644
--- a/components/script/dom/nodelist.rs
+++ b/components/script/dom/nodelist.rs
@@ -6,7 +6,6 @@ use dom::bindings::codegen::Bindings::NodeListBinding;
 use dom::bindings::codegen::Bindings::NodeListBinding::NodeListMethods;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, JSRef, Rootable, Temporary};
-use dom::bindings::trace::RootedVec;
 use dom::bindings::utils::{Reflector, reflect_dom_object};
 use dom::node::{Node, NodeHelpers};
 use dom::window::Window;
@@ -39,8 +38,10 @@ impl NodeList {
                            GlobalRef::Window(window), NodeListBinding::Wrap)
     }
 
-    pub fn new_simple_list(window: JSRef<Window>, elements: &RootedVec<JS<Node>>) -> Temporary<NodeList> {
-        NodeList::new(window, NodeListType::Simple((**elements).clone()))
+    pub fn new_simple_list<T>(window: JSRef<Window>, iter: T)
+                              -> Temporary<NodeList>
+                              where T: Iterator<Item=Temporary<Node>> {
+        NodeList::new(window, NodeListType::Simple(iter.map(JS::from_rooted).collect()))
     }
 
     pub fn new_child_list(window: JSRef<Window>, node: JSRef<Node>) -> Temporary<NodeList> {