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Merged
simonwuelker merged 5 commits into from
Apr 1, 2026
Merged

script: Let wheel, keyboard- and pointerevents be composed when fired by the user agent #43799

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7c19040
script: Let scroll, keypress and contextmenu events be composed
simonwuelker Mar 31, 2026
4ac5005
script: make pointerevents composed
simonwuelker Mar 31, 2026
38cd83b
Add tests for keyboard-related events
simonwuelker Mar 31, 2026
7438a10
script: Don't make keydown events composed
simonwuelker Mar 31, 2026
e882643
Update WPT expectations
simonwuelker Mar 31, 2026
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26 changes: 18 additions & 8 deletions components/script/dom/document/document_event_handler.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -689,6 +689,7 @@ impl DocumentEventHandler {

// Send pointermove event before mousemove.
let pointer_event = mouse_event.to_pointer_event(Atom::from("pointermove"), can_gc);
pointer_event.upcast::<Event>().set_composed(true);
pointer_event
.upcast::<Event>()
.fire(new_target.upcast(), can_gc);
Expand Down Expand Up @@ -840,8 +841,8 @@ impl DocumentEventHandler {
embedder_traits::MouseButtonAction::Down => atom!("mousedown"),
};

// From <https://w3c.github.io/uievents/#event-type-mousedown>
// and <https://w3c.github.io/uievents/#event-type-mouseup>:
// From <https://w3c.github.io/pointerevents/#dfn-mousedown>
// and <https://w3c.github.io/pointerevents/#mouseup>:
//
// UIEvent.detail: indicates the current click count incremented by one. For
// example, if no click happened before the mousedown, detail will contain
Expand Down Expand Up @@ -918,7 +919,7 @@ impl DocumentEventHandler {
);
}
},
// https://w3c.github.io/uievents/#handle-native-mouse-up
// https://w3c.github.io/pointerevents/#dfn-handle-native-mouse-up
MouseButtonAction::Up => {
// Step 6. Dispatch pointerup event.
let down_button_count = self.down_button_count.get();
Expand Down Expand Up @@ -960,8 +961,8 @@ impl DocumentEventHandler {
}
}

/// <https://w3c.github.io/uievents/#handle-native-mouse-click>
/// <https://w3c.github.io/uievents/#event-type-dblclick>
/// <https://w3c.github.io/pointerevents/#handle-native-mouse-click>
/// <https://w3c.github.io/pointerevents/#handle-native-mouse-double-click>
fn maybe_trigger_click_for_mouse_button_down_event(
&self,
event: MouseButtonEvent,
Expand All @@ -984,7 +985,7 @@ impl DocumentEventHandler {
return;
}

// From <https://w3c.github.io/uievents/#event-type-click>
// From <https://w3c.github.io/pointerevents/#click>
// > The click event type MUST be dispatched on the topmost event target indicated by the
// > pointer, when the user presses down and releases the primary pointer button.
// For nodes inside a text input UA shadow DOM, dispatch dblclick at the shadow host.
Expand Down Expand Up @@ -1032,15 +1033,15 @@ impl DocumentEventHandler {
}
}

/// <https://www.w3.org/TR/uievents/#maybe-show-context-menu>
/// <https://www.w3.org/TR/pointerevents4/#maybe-show-context-menu>
fn maybe_show_context_menu(
&self,
target: &EventTarget,
hit_test_result: &HitTestResult,
input_event: &ConstellationInputEvent,
can_gc: CanGc,
) {
// <https://w3c.github.io/uievents/#contextmenu>
// <https://w3c.github.io/pointerevents/#contextmenu>
let menu_event = PointerEvent::new(
&self.window, // window
"contextmenu".into(), // type
Expand Down Expand Up @@ -1074,6 +1075,7 @@ impl DocumentEventHandler {
vec![], // predicted_events
can_gc,
);
menu_event.upcast::<Event>().set_composed(true);

// Step 3. Let result = dispatch menuevent at target.
let result = menu_event.upcast::<Event>().fire(target, can_gc);
Expand Down Expand Up @@ -1372,6 +1374,12 @@ impl DocumentEventHandler {
);

let event = keyevent.upcast::<Event>();

// FIXME: https://github.com/servo/servo/issues/43809
if event.type_() != atom!("keydown") {
event.set_composed(true);
}

event.fire(target, can_gc);

let mut flags = event.flags();
Expand Down Expand Up @@ -1399,6 +1407,7 @@ impl DocumentEventHandler {
&keyboard_event.event,
can_gc,
);
keypress_event.upcast::<Event>().set_composed(true);
let event = keypress_event.upcast::<Event>();
event.fire(target, can_gc);
flags = event.flags();
Expand Down Expand Up @@ -1507,6 +1516,7 @@ impl DocumentEventHandler {

let dom_event = dom_event.upcast::<Event>();
dom_event.set_trusted(true);
dom_event.set_composed(true);
dom_event.fire(node.upcast(), can_gc);

dom_event.flags().into()
Expand Down
56 changes: 36 additions & 20 deletions components/script/dom/event/mouseevent.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -183,7 +183,7 @@ impl MouseEvent {
ev
}

/// <https://w3c.github.io/uievents/#initialize-a-mouseevent>
/// <https://w3c.github.io/pointerevents/#initialize-a-mouseevent>
#[expect(clippy::too_many_arguments)]
pub(crate) fn initialize_mouse_event(
&self,
Expand Down Expand Up @@ -230,7 +230,7 @@ impl MouseEvent {
can_gc: CanGc,
) -> DomRoot<Self> {
// These values come from the event tables in
// <https://w3c.github.io/uievents/#events-mouse-types>.
// <https://w3c.github.io/pointerevents/#mouse-event-types>.
let (bubbles, cancelable, composed) = match event_name {
FireMouseEventType::Move | FireMouseEventType::Over | FireMouseEventType::Out => {
(EventBubbles::Bubbles, EventCancelable::Cancelable, true)
Expand Down Expand Up @@ -269,8 +269,9 @@ impl MouseEvent {
mouse_event
}

/// Create a [MouseEvent] triggered by the embedder
/// <https://w3c.github.io/uievents/#create-a-cancelable-mouseevent-id>
/// Create a [MouseEvent] triggered by the embedder.
///
/// <https://w3c.github.io/pointerevents/#create-a-cancelable-mouseevent>
#[expect(clippy::too_many_arguments)]
pub(crate) fn for_platform_button_event(
event_type: Atom,
Expand Down Expand Up @@ -341,10 +342,15 @@ impl MouseEvent {
-1
};

// https://w3c.github.io/pointerevents/#dfn-attributes-and-default-actions
// For pointerenter and pointerleave events, the composed [DOM] attribute SHOULD be false;
// for all other pointer events in the table above, the attribute SHOULD be true.
let composed = !matches!(&*event_type, "pointerenter" | "pointerleave");

let window = self.global();
let window = window.as_window();

PointerEvent::new(
let pointer_event = PointerEvent::new(
window,
event_type,
EventBubbles::from(self.upcast::<Event>().Bubbles()),
Expand Down Expand Up @@ -374,7 +380,11 @@ impl MouseEvent {
vec![], // coalesced_events
vec![], // predicted_events
can_gc,
)
);

pointer_event.upcast::<Event>().set_composed(composed);

pointer_event
}

/// Create a PointerEvent for hover events (pointerover, pointerenter, pointerout, pointerleave).
Expand Down Expand Up @@ -431,6 +441,12 @@ impl MouseEvent {
can_gc,
);

// https://w3c.github.io/pointerevents/#dfn-attributes-and-default-actions
// For pointerenter and pointerleave events, the composed [DOM] attribute SHOULD be false;
// for all other pointer events in the table above, the attribute SHOULD be true.
let composed = !matches!(event_type, "pointerenter" | "pointerleave");
pointer_event.upcast::<Event>().set_composed(composed);

// Set trusted to match the source mouse event
pointer_event
.upcast::<Event>()
Expand All @@ -441,7 +457,7 @@ impl MouseEvent {
}

impl MouseEventMethods<crate::DomTypeHolder> for MouseEvent {
/// <https://w3c.github.io/uievents/#dom-mouseevent-mouseevent>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-constructor>
fn Constructor(
window: &Window,
proto: Option<HandleObject>,
Expand Down Expand Up @@ -480,22 +496,22 @@ impl MouseEventMethods<crate::DomTypeHolder> for MouseEvent {
Ok(event)
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-screenX>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-screenx>
fn ScreenX(&self) -> i32 {
self.screen_point.get().x
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-screenY>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-screeny>
fn ScreenY(&self) -> i32 {
self.screen_point.get().y
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-clientX>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-clientx>
fn ClientX(&self) -> i32 {
self.client_point.get().x
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-clientY>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-clienty>
fn ClientY(&self) -> i32 {
self.client_point.get().y
}
Expand Down Expand Up @@ -586,42 +602,42 @@ impl MouseEventMethods<crate::DomTypeHolder> for MouseEvent {
self.PageY()
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-ctrlkey>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-ctrlkey>
fn CtrlKey(&self) -> bool {
self.modifiers.get().contains(Modifiers::CONTROL)
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-shiftkey>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-shiftkey>
fn ShiftKey(&self) -> bool {
self.modifiers.get().contains(Modifiers::SHIFT)
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-altkey>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-altkey>
fn AltKey(&self) -> bool {
self.modifiers.get().contains(Modifiers::ALT)
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-metakey>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-metakey>
fn MetaKey(&self) -> bool {
self.modifiers.get().contains(Modifiers::META)
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-button>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-button>
fn Button(&self) -> i16 {
self.button.get()
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-buttons>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-buttons>
fn Buttons(&self) -> u16 {
self.buttons.get()
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-relatedTarget>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-relatedtarget>
fn GetRelatedTarget(&self) -> Option<DomRoot<EventTarget>> {
self.upcast::<Event>().related_target()
}

/// <https://w3c.github.io/uievents/#widl-MouseEvent-initMouseEvent>
/// <https://w3c.github.io/pointerevents/#dom-mouseevent-initmouseevent>
fn InitMouseEvent(
&self,
type_arg: DOMString,
Expand Down Expand Up @@ -696,7 +712,7 @@ impl MouseEventMethods<crate::DomTypeHolder> for MouseEvent {
self.uievent.IsTrusted()
}

/// <https://w3c.github.io/uievents/#dom-mouseevent-getmodifierstate>
/// <https://w3c.github.io/pointerevents/#dfn-getmodifierstate-keyarg>
fn GetModifierState(&self, key_arg: DOMString) -> bool {
self.modifiers
.get()
Expand Down
6 changes: 1 addition & 5 deletions components/script/dom/event/pointerevent.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,6 @@ use dom_struct::dom_struct;
use euclid::Point2D;
use js::rust::HandleObject;
use keyboard_types::Modifiers;
use script_bindings::inheritance::Castable;
use style::Atom;
use style_traits::CSSPixel;

Expand All @@ -21,7 +20,7 @@ use crate::dom::bindings::num::Finite;
use crate::dom::bindings::reflector::reflect_dom_object_with_proto;
use crate::dom::bindings::root::DomRoot;
use crate::dom::bindings::str::DOMString;
use crate::dom::event::{Event, EventBubbles, EventCancelable};
use crate::dom::event::{EventBubbles, EventCancelable};
use crate::dom::eventtarget::EventTarget;
use crate::dom::mouseevent::MouseEvent;
use crate::dom::window::Window;
Expand Down Expand Up @@ -191,8 +190,6 @@ impl PointerEvent {
can_gc: CanGc,
) -> DomRoot<PointerEvent> {
let ev = PointerEvent::new_uninitialized_with_proto(window, proto, can_gc);
// See <https://w3c.github.io/pointerevents/#attributes-and-default-actions>
let composed = &*event_type != "pointerenter" && &*event_type != "pointerleave";
ev.mouseevent.initialize_mouse_event(
event_type,
can_bubble,
Expand All @@ -208,7 +205,6 @@ impl PointerEvent {
related_target,
point_in_target,
);
ev.mouseevent.upcast::<Event>().set_composed(composed);
ev.pointer_id.set(pointer_id);
ev.width.set(width);
ev.height.set(height);
Expand Down
15 changes: 12 additions & 3 deletions components/script/dom/touch.rs
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -6,12 +6,13 @@ use std::f64::consts::PI;

use dom_struct::dom_struct;
use euclid::Point2D;
use script_bindings::inheritance::Castable;

use crate::dom::bindings::codegen::Bindings::TouchBinding::TouchMethods;
use crate::dom::bindings::num::Finite;
use crate::dom::bindings::reflector::{Reflector, reflect_dom_object};
use crate::dom::bindings::root::{DomRoot, MutDom};
use crate::dom::event::{EventBubbles, EventCancelable};
use crate::dom::event::{Event, EventBubbles, EventCancelable};
use crate::dom::eventtarget::EventTarget;
use crate::dom::pointerevent::PointerEvent;
use crate::dom::window::Window;
Expand Down Expand Up @@ -138,7 +139,7 @@ impl Touch {
_ => (EventBubbles::Bubbles, EventCancelable::from(is_cancelable)),
};

PointerEvent::new(
let pointer_event = PointerEvent::new(
window,
event_type.into(),
bubbles,
Expand Down Expand Up @@ -168,7 +169,15 @@ impl Touch {
vec![], // coalesced_events
vec![], // predicted_events
can_gc,
)
);

// https://w3c.github.io/pointerevents/#dfn-attributes-and-default-actions
// For pointerenter and pointerleave events, the composed [DOM] attribute SHOULD be false;
// for all other pointer events in the table above, the attribute SHOULD be true.
let composed = !matches!(event_type, "pointerenter" | "pointerleave");
pointer_event.upcast::<Event>().set_composed(composed);
Comment on lines +174 to +178

@mrobinson mrobinson Mar 31, 2026

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Maybe this should happen in PointerEvent::new so that it is applied consistently?

@simonwuelker simonwuelker Mar 31, 2026

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Only pointer events that are caused by a user action should be composed.

In other words, (new PointerEvent("pointerup").composed == false.

That's why the code needs to be here.

@simonwuelker simonwuelker Mar 31, 2026 •
edited
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Hmm actually the constructor does currently set the composed flag:

servo/components/script/dom/event/pointerevent.rs

Lines 194 to 195 in 11687b3

// See <https://w3c.github.io/pointerevents/#attributes-and-default-actions>
let composed = &*event_type != "pointerenter" && &*event_type != "pointerleave";

let's fix that...

@mrobinson mrobinson Mar 31, 2026 •
edited
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What we do for mouse events is have two constructors, one for system input events and one for synthetic events or constructed events.

@simonwuelker simonwuelker Mar 31, 2026

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Hmm pointerevents are already (mostly) constructed in MouseEvent::to_pointer_event and MouseEvent::to_pointer_hover_event we can set the flags there.


pointer_event
}
}

Expand Down
6 changes: 3 additions & 3 deletions components/script_bindings/webidls/MouseEvent.webidl
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Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */

// https://w3c.github.io/uievents/#interface-mouseevent
// https://w3c.github.io/pointerevents/#dom-mouseevent
[Exposed=Window]
interface MouseEvent : UIEvent {
[Throws] constructor(DOMString typeArg, optional MouseEventInit mouseEventInitDict = {});
Expand All @@ -27,7 +27,7 @@ interface MouseEvent : UIEvent {
boolean getModifierState (DOMString keyArg);
};

// https://w3c.github.io/uievents/#dictdef-eventmodifierinit
// https://w3c.github.io/pointerevents/#dom-mouseeventinit
dictionary MouseEventInit : EventModifierInit {
long screenX = 0;
long screenY = 0;
Expand All @@ -38,7 +38,7 @@ dictionary MouseEventInit : EventModifierInit {
EventTarget? relatedTarget = null;
};

// https://w3c.github.io/uievents/#idl-interface-MouseEvent-initializers
// https://w3c.github.io/pointerevents/#dom-mouseevent-initmouseevent
partial interface MouseEvent {
// Deprecated in DOM Level 3
undefined initMouseEvent (DOMString typeArg, boolean bubblesArg, boolean cancelableArg,
Expand Down
4 changes: 2 additions & 2 deletions components/script_bindings/webidls/WheelEvent.webidl
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Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */

// https://w3c.github.io/uievents/#interface-wheelevent
// https://w3c.github.io/pointerevents/#interface-wheelevent
[Exposed=Window]
interface WheelEvent : MouseEvent {
[Throws] constructor(DOMString typeArg, optional WheelEventInit wheelEventInitDict = {});
Expand All @@ -15,7 +15,7 @@ interface WheelEvent : MouseEvent {
readonly attribute unsigned long deltaMode;
};

// https://w3c.github.io/uievents/#idl-wheeleventinit
// https://w3c.github.io/pointerevents/#dom-wheeleventinit
dictionary WheelEventInit : MouseEventInit {
double deltaX = 0.0;
double deltaY = 0.0;
Expand Down
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