diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index a8f9ce28db5..a53c37f84e4 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -9,6 +9,7 @@ use dom::bindings::codegen::Bindings::HTMLButtonElementBinding::HTMLButtonElemen
 use dom::bindings::codegen::Bindings::HTMLFormElementBinding;
 use dom::bindings::codegen::Bindings::HTMLFormElementBinding::HTMLFormElementMethods;
 use dom::bindings::codegen::Bindings::HTMLInputElementBinding::HTMLInputElementMethods;
+use dom::bindings::codegen::Bindings::HTMLTextAreaElementBinding::HTMLTextAreaElementMethods;
 use dom::bindings::conversions::DerivedFrom;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::inheritance::{Castable, ElementTypeId, HTMLElementTypeId, NodeTypeId};
@@ -293,17 +294,18 @@ impl HTMLFormElement {
         let node = self.upcast::<Node>();
         // FIXME(#3553): This is an incorrect way of getting controls owned
         //               by the form, but good enough until html5ever lands
-        node.traverse_preorder().filter_map(|child| {
+        let mut data_set = Vec::new();
+        for child in node.traverse_preorder() {
             // Step 3.1: The field element is disabled.
             match child.downcast::<Element>() {
                 Some(el) if !el.get_disabled_state() => (),
-                _ => return None,
+                _ => continue,
             }
 
             // Step 3.1: The field element has a datalist element ancestor.
             if child.ancestors()
                     .any(|a| Root::downcast::<HTMLDataListElement>(a).is_some()) {
-                return None;
+                continue;
             }
             match child.type_id() {
                 NodeTypeId::Element(ElementTypeId::HTMLElement(element)) => {
@@ -311,21 +313,37 @@ impl HTMLFormElement {
                         HTMLElementTypeId::HTMLInputElement => {
                             let input = child.downcast::<HTMLInputElement>().unwrap();
                             // Step 3.2-3.7
-                            input.get_form_datum(submitter)
+                            if let Some(datum) = input.get_form_datum(submitter) {
+                                data_set.push(datum);
+                            }
                         }
                         HTMLElementTypeId::HTMLButtonElement |
-                        HTMLElementTypeId::HTMLSelectElement |
-                        HTMLElementTypeId::HTMLObjectElement |
-                        HTMLElementTypeId::HTMLTextAreaElement => {
+                        HTMLElementTypeId::HTMLObjectElement => {
                             // Unimplemented
-                            None
+                            ()
                         }
-                        _ => None
+                        HTMLElementTypeId::HTMLSelectElement => {
+                            let select = child.downcast::<HTMLSelectElement>().unwrap();
+                            select.push_form_data(&mut data_set);
+                        }
+                        HTMLElementTypeId::HTMLTextAreaElement => {
+                            let textarea = child.downcast::<HTMLTextAreaElement>().unwrap();
+                            let name = textarea.Name();
+                            if !name.is_empty() {
+                                data_set.push(FormDatum {
+                                    ty: textarea.Type(),
+                                    name: name,
+                                    value: textarea.Value()
+                                });
+                            }
+                        }
+                        _ => ()
                     }
                 }
-                _ => None
+                _ => ()
             }
-        }).collect()
+        }
+        data_set
         // TODO: Handle `dirnames` (needs directionality support)
         //       https://html.spec.whatwg.org/multipage/#the-directionality
     }
diff --git a/components/script/dom/htmlselectelement.rs b/components/script/dom/htmlselectelement.rs
index daf4d6f9ba5..6db068d6da2 100644
--- a/components/script/dom/htmlselectelement.rs
+++ b/components/script/dom/htmlselectelement.rs
@@ -14,7 +14,7 @@ use dom::document::Document;
 use dom::element::{AttributeMutation, Element};
 use dom::htmlelement::HTMLElement;
 use dom::htmlfieldsetelement::HTMLFieldSetElement;
-use dom::htmlformelement::{FormControl, HTMLFormElement};
+use dom::htmlformelement::{FormControl, FormDatum, HTMLFormElement};
 use dom::htmloptionelement::HTMLOptionElement;
 use dom::node::{Node, UnbindContext, window_from_node};
 use dom::nodelist::NodeList;
@@ -82,6 +82,23 @@ impl HTMLSelectElement {
         }
     }
 
+    pub fn push_form_data(&self, data_set: &mut Vec<FormDatum>) {
+        let node = self.upcast::<Node>();
+        if self.Name().is_empty() {
+            return;
+        }
+        for opt in node.traverse_preorder().filter_map(Root::downcast::<HTMLOptionElement>) {
+            let element = opt.upcast::<Element>();
+            if opt.Selected() && element.get_enabled_state() {
+                data_set.push(FormDatum {
+                    ty: self.Type(),
+                    name: self.Name(),
+                    value: opt.Value()
+                });
+            }
+        }
+    }
+
     // https://html.spec.whatwg.org/multipage/#concept-select-pick
     pub fn pick_option(&self, picked: &HTMLOptionElement) {
         if !self.Multiple() {
diff --git a/tests/wpt/metadata/html/semantics/forms/form-submission-0/url-encoded.html.ini b/tests/wpt/metadata/html/semantics/forms/form-submission-0/url-encoded.html.ini
deleted file mode 100644
index 4f322ca7011..00000000000
--- a/tests/wpt/metadata/html/semantics/forms/form-submission-0/url-encoded.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[url-encoded.html]
-  type: testharness
-  [textarea.simple]
-    expected: FAIL
-