Auto merge of #9237 - frewsxcv:htmlformelement-elements, r=KiChjang

Implement HTMLFormElement::Elements

Fixes #8566

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6 files changed, 141 insertions, 2 deletions

diff --git a/components/script/dom/htmlcollection.rs b/components/script/dom/htmlcollection.rs
index 1e80481ac68..ec71502bf42 100644
--- a/components/script/dom/htmlcollection.rs
+++ b/components/script/dom/htmlcollection.rs
@@ -66,7 +66,7 @@ pub struct HTMLCollection {
 
 impl HTMLCollection {
     #[allow(unrooted_must_root)]
-    fn new_inherited(root: &Node, filter: Box<CollectionFilter + 'static>) -> HTMLCollection {
+    pub fn new_inherited(root: &Node, filter: Box<CollectionFilter + 'static>) -> HTMLCollection {
         HTMLCollection {
             reflector_: Reflector::new(),
             root: JS::from_ref(root),
diff --git a/components/script/dom/htmlformcontrolscollection.rs b/components/script/dom/htmlformcontrolscollection.rs
new file mode 100644
index 00000000000..2b9b3060a86
--- /dev/null
+++ b/components/script/dom/htmlformcontrolscollection.rs
@@ -0,0 +1,62 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use dom::bindings::codegen::Bindings::HTMLCollectionBinding::HTMLCollectionMethods;
+use dom::bindings::codegen::Bindings::HTMLFormControlsCollectionBinding;
+use dom::bindings::codegen::Bindings::HTMLFormControlsCollectionBinding::HTMLFormControlsCollectionMethods;
+use dom::bindings::global::GlobalRef;
+use dom::bindings::js::Root;
+use dom::bindings::reflector::reflect_dom_object;
+use dom::element::Element;
+use dom::htmlcollection::{CollectionFilter, HTMLCollection};
+use dom::node::Node;
+use dom::window::Window;
+use util::str::DOMString;
+
+#[dom_struct]
+pub struct HTMLFormControlsCollection {
+    collection: HTMLCollection,
+}
+
+impl HTMLFormControlsCollection {
+    fn new_inherited(root: &Node, filter: Box<CollectionFilter + 'static>) -> HTMLFormControlsCollection {
+        HTMLFormControlsCollection {
+            collection: HTMLCollection::new_inherited(root, filter)
+        }
+    }
+
+    pub fn new(window: &Window, root: &Node, filter: Box<CollectionFilter + 'static>)
+        -> Root<HTMLFormControlsCollection>
+    {
+        reflect_dom_object(box HTMLFormControlsCollection::new_inherited(root, filter),
+                           GlobalRef::Window(window),
+                           HTMLFormControlsCollectionBinding::Wrap)
+    }
+
+    // FIXME: This shouldn't need to be implemented here since HTMLCollection (the parent of
+    // HTMLFormControlsCollection) implements Length
+    pub fn Length(&self) -> u32 {
+        self.collection.Length()
+    }
+}
+
+impl HTMLFormControlsCollectionMethods for HTMLFormControlsCollection {
+    // https://html.spec.whatwg.org/multipage/#dom-htmlformcontrolscollection-nameditem
+    fn NamedGetter(&self, name: DOMString, found: &mut bool) -> Option<Root<Element>> {
+        self.collection.NamedGetter(name, found)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#the-htmlformcontrolscollection-interface:supported-property-names
+    fn SupportedPropertyNames(&self) -> Vec<DOMString> {
+        self.collection.SupportedPropertyNames()
+    }
+
+    // FIXME: This shouldn't need to be implemented here since HTMLCollection (the parent of
+    // HTMLFormControlsCollection) implements IndexedGetter
+    //
+    // https://dom.spec.whatwg.org/#dom-htmlcollection-item
+    fn IndexedGetter(&self, index: u32, found: &mut bool) -> Option<Root<Element>> {
+        self.collection.IndexedGetter(index, found)
+    }
+}
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index 512a0d6a56c..072231d4054 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -20,10 +20,14 @@ use dom::element::Element;
 use dom::event::{EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
 use dom::htmlbuttonelement::HTMLButtonElement;
+use dom::htmlcollection::CollectionFilter;
 use dom::htmldatalistelement::HTMLDataListElement;
 use dom::htmlelement::HTMLElement;
+use dom::htmlfieldsetelement::HTMLFieldSetElement;
+use dom::htmlformcontrolscollection::HTMLFormControlsCollection;
 use dom::htmlinputelement::HTMLInputElement;
 use dom::htmlobjectelement::HTMLObjectElement;
+use dom::htmloutputelement::HTMLOutputElement;
 use dom::htmlselectelement::HTMLSelectElement;
 use dom::htmltextareaelement::HTMLTextAreaElement;
 use dom::node::{Node, document_from_node, window_from_node};
@@ -135,6 +139,62 @@ impl HTMLFormElementMethods for HTMLFormElement {
     fn Reset(&self) {
         self.reset(ResetFrom::FromFormResetMethod);
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-form-elements
+    fn Elements(&self) -> Root<HTMLFormControlsCollection> {
+        #[derive(JSTraceable, HeapSizeOf)]
+        struct ElementsFilter {
+            form: Root<HTMLFormElement>
+        }
+        impl CollectionFilter for ElementsFilter {
+            fn filter<'a>(&self, elem: &'a Element, _root: &'a Node) -> bool {
+                let form_owner = match elem.upcast::<Node>().type_id() {
+                    NodeTypeId::Element(ElementTypeId::HTMLElement(t)) => {
+                        match t {
+                            HTMLElementTypeId::HTMLButtonElement => {
+                                elem.downcast::<HTMLButtonElement>().unwrap().form_owner()
+                            }
+                            HTMLElementTypeId::HTMLFieldSetElement => {
+                                elem.downcast::<HTMLFieldSetElement>().unwrap().form_owner()
+                            }
+                            HTMLElementTypeId::HTMLInputElement => {
+                                let input_elem = elem.downcast::<HTMLInputElement>().unwrap();
+                                if input_elem.type_() == atom!("image") {
+                                    return false;
+                                }
+                                input_elem.form_owner()
+                            }
+                            HTMLElementTypeId::HTMLObjectElement => {
+                                elem.downcast::<HTMLObjectElement>().unwrap().form_owner()
+                            }
+                            HTMLElementTypeId::HTMLOutputElement => {
+                                elem.downcast::<HTMLOutputElement>().unwrap().form_owner()
+                            }
+                            HTMLElementTypeId::HTMLSelectElement => {
+                                elem.downcast::<HTMLSelectElement>().unwrap().form_owner()
+                            }
+                            HTMLElementTypeId::HTMLTextAreaElement => {
+                                elem.downcast::<HTMLTextAreaElement>().unwrap().form_owner()
+                            }
+                            _ => {
+                                debug_assert!(!elem.downcast::<HTMLElement>().unwrap().is_listed_element());
+                                return false;
+                            }
+                        }
+                    }
+                    _ => return false,
+                };
+
+                match form_owner {
+                    Some(form_owner) => form_owner == self.form,
+                    None => false,
+                }
+            }
+        }
+        let filter = box ElementsFilter { form: Root::from_ref(self) };
+        let window = window_from_node(self);
+        HTMLFormControlsCollection::new(window.r(), self.upcast(), filter)
+    }
 }
 
 #[derive(Copy, Clone, HeapSizeOf, PartialEq)]
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index 89b0745dbc3..38abcd56ddd 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -272,6 +272,7 @@ pub mod htmlelement;
 pub mod htmlembedelement;
 pub mod htmlfieldsetelement;
 pub mod htmlfontelement;
+pub mod htmlformcontrolscollection;
 pub mod htmlformelement;
 pub mod htmlframeelement;
 pub mod htmlframesetelement;
diff --git a/components/script/dom/webidls/HTMLFormControlsCollection.webidl b/components/script/dom/webidls/HTMLFormControlsCollection.webidl
new file mode 100644
index 00000000000..e7f2e84a566
--- /dev/null
+++ b/components/script/dom/webidls/HTMLFormControlsCollection.webidl
@@ -0,0 +1,16 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#htmlformcontrolscollection
+interface HTMLFormControlsCollection : HTMLCollection {
+  // inherits length and item()
+  // getter (RadioNodeList or Element)? namedItem(DOMString name); // shadows inherited namedItem()
+};
+
+/*
+interface RadioNodeList : NodeList {
+  attribute DOMString value;
+};
+*/
diff --git a/components/script/dom/webidls/HTMLFormElement.webidl b/components/script/dom/webidls/HTMLFormElement.webidl
index e2423dcce6c..4fde856a6a5 100644
--- a/components/script/dom/webidls/HTMLFormElement.webidl
+++ b/components/script/dom/webidls/HTMLFormElement.webidl
@@ -16,7 +16,7 @@ interface HTMLFormElement : HTMLElement {
            attribute boolean noValidate;
            attribute DOMString target;
 
-  //[SameObject] readonly attribute HTMLFormControlsCollection elements;
+  [SameObject] readonly attribute HTMLFormControlsCollection elements;
   //readonly attribute long length;
   //getter Element (unsigned long index);
   //getter (RadioNodeList or Element) (DOMString name);