Auto merge of #9030 - askobara:refactoring-add-htmlformelement-fire_event, r=Manishearth

Add helper method HTMLFormElement::fire_event

Fixes #8777

<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/9030)
<!-- Reviewable:end -->

8 files changed, 62 insertions, 72 deletions

diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index b2033a2a92e..d1e529f3bfa 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -558,12 +558,8 @@ impl Document {
 
         self.ready_state.set(state);
 
-        let event = Event::new(GlobalRef::Window(&self.window),
-                               atom!("readystatechange"),
-                               EventBubbles::DoesNotBubble,
-                               EventCancelable::NotCancelable);
-        let target = self.upcast::<EventTarget>();
-        let _ = event.fire(target);
+        self.upcast::<EventTarget>().fire_simple_event("readystatechange",
+                                                       GlobalRef::Window(&self.window));
     }
 
     /// Return whether scripting is enabled or not
diff --git a/components/script/dom/eventtarget.rs b/components/script/dom/eventtarget.rs
index 612c3d78b11..94998185507 100644
--- a/components/script/dom/eventtarget.rs
+++ b/components/script/dom/eventtarget.rs
@@ -11,12 +11,12 @@ use dom::bindings::codegen::Bindings::EventListenerBinding::EventListener;
 use dom::bindings::codegen::Bindings::EventTargetBinding::EventTargetMethods;
 use dom::bindings::codegen::UnionTypes::EventOrString;
 use dom::bindings::error::{Error, Fallible, report_pending_exception};
-use dom::bindings::global::global_root_from_reflector;
+use dom::bindings::global::{GlobalRef, global_root_from_reflector};
 use dom::bindings::inheritance::{Castable, EventTargetTypeId};
 use dom::bindings::js::Root;
 use dom::bindings::reflector::{Reflectable, Reflector};
 use dom::errorevent::ErrorEvent;
-use dom::event::Event;
+use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::eventdispatcher::dispatch_event;
 use dom::virtualmethods::VirtualMethods;
 use dom::window::Window;
@@ -329,6 +329,24 @@ impl EventTarget {
     pub fn has_handlers(&self) -> bool {
         !self.handlers.borrow().is_empty()
     }
+
+    /// Implements https://html.spec.whatwg.org/multipage/#fire-a-simple-event
+    pub fn fire_simple_event(&self, name: &str, win: GlobalRef) -> Root<Event> {
+        self.fire_simple_event_params(name, EventBubbles::DoesNotBubble,
+                                      EventCancelable::NotCancelable, win)
+    }
+
+    /// Implements more customizable variant of EventTarget::fire_simple_event.
+    pub fn fire_simple_event_params(&self, name: &str,
+                                    bubbles: EventBubbles,
+                                    cancelable: EventCancelable,
+                                    win: GlobalRef) -> Root<Event> {
+        let event = Event::new(win, Atom::from(name), bubbles, cancelable);
+
+        event.fire(self);
+
+        event
+    }
 }
 
 impl EventTargetMethods for EventTarget {
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index f3c98dec0d9..6515eb58471 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -16,7 +16,7 @@ use dom::bindings::js::{Root};
 use dom::bindings::reflector::Reflectable;
 use dom::document::Document;
 use dom::element::Element;
-use dom::event::{Event, EventBubbles, EventCancelable};
+use dom::event::{EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
 use dom::htmlbuttonelement::HTMLButtonElement;
 use dom::htmldatalistelement::HTMLDataListElement;
@@ -169,23 +169,18 @@ impl HTMLFormElement {
         {
             if self.interactive_validation().is_err() {
                 // TODO: Implement event handlers on all form control elements
-                // XXXKiChjang: We're also calling the following two statements quite often,
-                //              we should refactor it into a function
-                let event = Event::new(GlobalRef::Window(win.r()),
-                                       atom!("invalid"),
-                                       EventBubbles::DoesNotBubble,
-                                       EventCancelable::NotCancelable);
-                event.fire(self.upcast());
+                self.upcast::<EventTarget>()
+                    .fire_simple_event("invalid", GlobalRef::Window(win.r()));
                 return;
             }
         }
         // Step 5
         if submit_method_flag == SubmittedFrom::NotFromFormSubmitMethod {
-            let event = Event::new(GlobalRef::Window(win.r()),
-                                   atom!("submit"),
-                                   EventBubbles::Bubbles,
-                                   EventCancelable::Cancelable);
-            event.fire(self.upcast());
+            let event = self.upcast::<EventTarget>()
+                .fire_simple_event_params("submit",
+                                          EventBubbles::Bubbles,
+                                          EventCancelable::Cancelable,
+                                          GlobalRef::Window(win.r()));
             if event.DefaultPrevented() {
                 return;
             }
@@ -280,11 +275,11 @@ impl HTMLFormElement {
         // Step 5-6
         let win = window_from_node(self);
         let unhandled_invalid_controls = invalid_controls.into_iter().filter_map(|field| {
-            let event = Event::new(GlobalRef::Window(win.r()),
-                                   atom!("invalid"),
-                                   EventBubbles::DoesNotBubble,
-                                   EventCancelable::Cancelable);
-            event.fire(field.as_event_target());
+            let event = field.as_event_target()
+                .fire_simple_event_params("invalid",
+                                          EventBubbles::DoesNotBubble,
+                                          EventCancelable::Cancelable,
+                                          GlobalRef::Window(win.r()));
             if !event.DefaultPrevented() { return Some(field); }
             None
         }).collect::<Vec<FormSubmittableElement>>();
@@ -393,11 +388,11 @@ impl HTMLFormElement {
         }
 
         let win = window_from_node(self);
-        let event = Event::new(GlobalRef::Window(win.r()),
-                               atom!("reset"),
-                               EventBubbles::Bubbles,
-                               EventCancelable::Cancelable);
-        event.fire(self.upcast());
+        let event = self.upcast::<EventTarget>()
+            .fire_simple_event_params("reset",
+                                      EventBubbles::Bubbles,
+                                      EventCancelable::Cancelable,
+                                      GlobalRef::Window(win.r()));
         if event.DefaultPrevented() {
             return;
         }
@@ -430,6 +425,7 @@ impl HTMLFormElement {
         };
         self.marked_for_reset.set(false);
     }
+
 }
 
 // TODO: add file support
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 8b3def1c7cb..c51e98d8f92 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -17,7 +17,8 @@ use dom::bindings::reflector::Reflectable;
 use dom::customevent::CustomEvent;
 use dom::document::Document;
 use dom::element::{AttributeMutation, Element, RawLayoutElementHelpers};
-use dom::event::{Event, EventBubbles, EventCancelable};
+use dom::event::Event;
+use dom::eventtarget::EventTarget;
 use dom::htmlelement::HTMLElement;
 use dom::node::{Node, window_from_node};
 use dom::urlhelper::UrlHelper;
@@ -208,12 +209,7 @@ impl HTMLIFrameElement {
 
         // Step 4
         let window = window_from_node(self);
-        let event = Event::new(GlobalRef::Window(window.r()),
-                               atom!("load"),
-                               EventBubbles::DoesNotBubble,
-                               EventCancelable::NotCancelable);
-        event.fire(self.upcast());
-
+        self.upcast::<EventTarget>().fire_simple_event("load", GlobalRef::Window(window.r()));
         // TODO Step 5 - unset child document `mut iframe load` flag
     }
 }
diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index de25eb87369..39b485d6d6c 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/components/script/dom/htmlimageelement.rs
@@ -15,7 +15,7 @@ use dom::bindings::js::{LayoutJS, Root};
 use dom::bindings::refcounted::Trusted;
 use dom::document::Document;
 use dom::element::AttributeMutation;
-use dom::event::{Event, EventBubbles, EventCancelable};
+use dom::eventtarget::EventTarget;
 use dom::htmlelement::HTMLElement;
 use dom::node::{Node, NodeDamage, document_from_node, window_from_node};
 use dom::virtualmethods::VirtualMethods;
@@ -77,12 +77,7 @@ impl Runnable for ImageResponseHandlerRunnable {
 
         // Fire image.onload
         let window = window_from_node(document.r());
-        let event = Event::new(GlobalRef::Window(window.r()),
-                               atom!("load"),
-                               EventBubbles::DoesNotBubble,
-                               EventCancelable::NotCancelable);
-        event.fire(element.upcast());
-
+        element.upcast::<EventTarget>().fire_simple_event("load", GlobalRef::Window(window.r()));
         // Trigger reflow
         window.add_pending_reflow();
     }
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index 35d04fed47e..a7143133b05 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -858,19 +858,16 @@ impl Activatable for HTMLInputElement {
                 // https://html.spec.whatwg.org/multipage/#radio-button-state-(type=radio):activation-behavior
                 if self.mutable() {
                     let win = window_from_node(self);
-                    let target = self.upcast();
-
-                    let event = Event::new(GlobalRef::Window(win.r()),
-                                           atom!("input"),
-                                           EventBubbles::Bubbles,
-                                           EventCancelable::NotCancelable);
-                    event.fire(target);
-
-                    let event = Event::new(GlobalRef::Window(win.r()),
-                                           atom!("change"),
-                                           EventBubbles::Bubbles,
-                                           EventCancelable::NotCancelable);
-                    event.fire(target);
+                    let target = self.upcast::<EventTarget>();
+
+                    target.fire_simple_event_params("input",
+                                                    EventBubbles::Bubbles,
+                                                    EventCancelable::NotCancelable,
+                                                    GlobalRef::Window(win.r()));
+                    target.fire_simple_event_params("change",
+                                                    EventBubbles::Bubbles,
+                                                    EventCancelable::NotCancelable,
+                                                    GlobalRef::Window(win.r()));
                 }
             },
             _ => ()
diff --git a/components/script/dom/websocket.rs b/components/script/dom/websocket.rs
index b7a07d494cb..8f008255993 100644
--- a/components/script/dom/websocket.rs
+++ b/components/script/dom/websocket.rs
@@ -498,10 +498,7 @@ impl Runnable for ConnectionEstablishedTask {
         // Step 5: Cookies.
 
         // Step 6.
-        let event = Event::new(global.r(), atom!("open"),
-                               EventBubbles::DoesNotBubble,
-                               EventCancelable::NotCancelable);
-        event.fire(ws.upcast());
+        ws.upcast().fire_simple_event("open", global.r());
     }
 }
 
@@ -539,11 +536,10 @@ impl Runnable for CloseTask {
             ws.full.set(false);
             //A Bad close
             ws.clean_close.set(false);
-            let event = Event::new(global.r(),
-                                   atom!("error"),
-                                   EventBubbles::DoesNotBubble,
-                                   EventCancelable::Cancelable);
-            event.fire(ws.upcast());
+            ws.upcast().fire_simple_event_params("error",
+                                                 EventBubbles::DoesNotBubble,
+                                                 EventCancelable::Cancelable,
+                                                 global.r());
         }
         let reason = ws.reason.borrow().clone();
         /*In addition, we also have to fire a close even if error event fired
diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 2253d5e6dfb..5ca3d3316fc 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -126,11 +126,7 @@ impl Worker {
     pub fn dispatch_simple_error(address: TrustedWorkerAddress) {
         let worker = address.root();
         let global = worker.r().global.root();
-        let event = Event::new(global.r(),
-                               atom!("error"),
-                               EventBubbles::DoesNotBubble,
-                               EventCancelable::NotCancelable);
-        event.fire(worker.upcast());
+        worker.upcast().fire_simple_event("error", global.r());
     }
 
     pub fn handle_error_message(address: TrustedWorkerAddress, message: DOMString,