script/dom/
event.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::cell::Cell;
6use std::default::Default;
7
8use base::cross_process_instant::CrossProcessInstant;
9use bitflags::bitflags;
10use devtools_traits::{TimelineMarker, TimelineMarkerType};
11use dom_struct::dom_struct;
12use embedder_traits::InputEventResult;
13use js::rust::HandleObject;
14use keyboard_types::{Key, NamedKey};
15use script_bindings::codegen::GenericBindings::PointerEventBinding::PointerEventMethods;
16use script_bindings::match_domstring_ascii;
17use stylo_atoms::Atom;
18
19use crate::dom::bindings::callback::ExceptionHandling;
20use crate::dom::bindings::cell::DomRefCell;
21use crate::dom::bindings::codegen::Bindings::EventBinding;
22use crate::dom::bindings::codegen::Bindings::EventBinding::{EventConstants, EventMethods};
23use crate::dom::bindings::codegen::Bindings::NodeBinding::GetRootNodeOptions;
24use crate::dom::bindings::codegen::Bindings::NodeBinding::Node_Binding::NodeMethods;
25use crate::dom::bindings::codegen::Bindings::PerformanceBinding::DOMHighResTimeStamp;
26use crate::dom::bindings::codegen::Bindings::ShadowRootBinding::{
27    ShadowRootMethods, ShadowRootMode,
28};
29use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
30use crate::dom::bindings::error::Fallible;
31use crate::dom::bindings::inheritance::Castable;
32use crate::dom::bindings::refcounted::Trusted;
33use crate::dom::bindings::reflector::{DomGlobal, Reflector, reflect_dom_object_with_proto};
34use crate::dom::bindings::root::{Dom, DomRoot, MutNullableDom};
35use crate::dom::bindings::str::DOMString;
36use crate::dom::element::Element;
37use crate::dom::eventtarget::{EventListeners, EventTarget, ListenerPhase};
38use crate::dom::globalscope::GlobalScope;
39use crate::dom::html::htmlinputelement::InputActivationState;
40use crate::dom::html::htmlslotelement::HTMLSlotElement;
41use crate::dom::mouseevent::MouseEvent;
42use crate::dom::node::{Node, NodeTraits};
43use crate::dom::shadowroot::ShadowRoot;
44use crate::dom::types::{KeyboardEvent, PointerEvent, UserActivation};
45use crate::dom::virtualmethods::vtable_for;
46use crate::dom::window::Window;
47use crate::script_runtime::CanGc;
48use crate::task::TaskOnce;
49
50/// <https://dom.spec.whatwg.org/#concept-event>
51#[dom_struct]
52pub(crate) struct Event {
53    reflector_: Reflector,
54
55    /// <https://dom.spec.whatwg.org/#dom-event-currenttarget>
56    current_target: MutNullableDom<EventTarget>,
57
58    /// <https://dom.spec.whatwg.org/#event-target>
59    target: MutNullableDom<EventTarget>,
60
61    /// <https://dom.spec.whatwg.org/#dom-event-type>
62    #[no_trace]
63    type_: DomRefCell<Atom>,
64
65    /// <https://dom.spec.whatwg.org/#dom-event-eventphase>
66    phase: Cell<EventPhase>,
67
68    /// The various specification-defined flags set on this event.
69    flags: Cell<EventFlags>,
70
71    /// <https://dom.spec.whatwg.org/#dom-event-cancelable>
72    cancelable: Cell<bool>,
73
74    /// <https://dom.spec.whatwg.org/#dom-event-bubbles>
75    bubbles: Cell<bool>,
76
77    /// <https://dom.spec.whatwg.org/#dom-event-istrusted>
78    is_trusted: Cell<bool>,
79
80    /// <https://dom.spec.whatwg.org/#dom-event-timestamp>
81    #[no_trace]
82    time_stamp: CrossProcessInstant,
83
84    /// <https://dom.spec.whatwg.org/#event-path>
85    path: DomRefCell<Vec<EventPathSegment>>,
86
87    /// <https://dom.spec.whatwg.org/#event-relatedtarget>
88    related_target: MutNullableDom<EventTarget>,
89}
90
91/// An element on an [event path](https://dom.spec.whatwg.org/#event-path)
92#[derive(JSTraceable, MallocSizeOf)]
93#[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
94pub(crate) struct EventPathSegment {
95    /// <https://dom.spec.whatwg.org/#event-path-invocation-target>
96    invocation_target: Dom<EventTarget>,
97
98    /// <https://dom.spec.whatwg.org/#event-path-invocation-target-in-shadow-tree>
99    invocation_target_in_shadow_tree: bool,
100
101    /// <https://dom.spec.whatwg.org/#event-path-shadow-adjusted-target>
102    shadow_adjusted_target: Option<Dom<EventTarget>>,
103
104    /// <https://dom.spec.whatwg.org/#event-path-relatedtarget>
105    related_target: Option<Dom<EventTarget>>,
106
107    /// <https://dom.spec.whatwg.org/#event-path-root-of-closed-tree>
108    root_of_closed_tree: bool,
109
110    /// <https://dom.spec.whatwg.org/#event-path-slot-in-closed-tree>
111    slot_in_closed_tree: bool,
112}
113
114impl Event {
115    pub(crate) fn new_inherited() -> Event {
116        Event {
117            reflector_: Reflector::new(),
118            current_target: Default::default(),
119            target: Default::default(),
120            type_: DomRefCell::new(atom!("")),
121            phase: Cell::new(EventPhase::None),
122            flags: Cell::new(EventFlags::empty()),
123            cancelable: Cell::new(false),
124            bubbles: Cell::new(false),
125            is_trusted: Cell::new(false),
126            time_stamp: CrossProcessInstant::now(),
127            path: DomRefCell::default(),
128            related_target: Default::default(),
129        }
130    }
131
132    pub(crate) fn new_uninitialized(global: &GlobalScope, can_gc: CanGc) -> DomRoot<Event> {
133        Self::new_uninitialized_with_proto(global, None, can_gc)
134    }
135
136    pub(crate) fn new_uninitialized_with_proto(
137        global: &GlobalScope,
138        proto: Option<HandleObject>,
139        can_gc: CanGc,
140    ) -> DomRoot<Event> {
141        reflect_dom_object_with_proto(Box::new(Event::new_inherited()), global, proto, can_gc)
142    }
143
144    pub(crate) fn new(
145        global: &GlobalScope,
146        type_: Atom,
147        bubbles: EventBubbles,
148        cancelable: EventCancelable,
149        can_gc: CanGc,
150    ) -> DomRoot<Event> {
151        Self::new_with_proto(global, None, type_, bubbles, cancelable, can_gc)
152    }
153
154    fn new_with_proto(
155        global: &GlobalScope,
156        proto: Option<HandleObject>,
157        type_: Atom,
158        bubbles: EventBubbles,
159        cancelable: EventCancelable,
160        can_gc: CanGc,
161    ) -> DomRoot<Event> {
162        let event = Event::new_uninitialized_with_proto(global, proto, can_gc);
163
164        // NOTE: The spec doesn't tell us to call init event here, it just happens to do what we need.
165        event.init_event(type_, bool::from(bubbles), bool::from(cancelable));
166        event
167    }
168
169    /// <https://dom.spec.whatwg.org/#dom-event-initevent>
170    /// and <https://dom.spec.whatwg.org/#concept-event-initialize>
171    pub(crate) fn init_event(&self, type_: Atom, bubbles: bool, cancelable: bool) {
172        // https://dom.spec.whatwg.org/#dom-event-initevent
173        if self.has_flag(EventFlags::Dispatch) {
174            return;
175        }
176
177        // https://dom.spec.whatwg.org/#concept-event-initialize
178        // Step 1. Set event’s initialized flag.
179        self.set_flags(EventFlags::Initialized);
180
181        // Step 2. Unset event’s stop propagation flag, stop immediate propagation flag, and canceled flag.
182        self.unset_flags(EventFlags::StopPropagation);
183        self.unset_flags(EventFlags::StopImmediatePropagation);
184        self.unset_flags(EventFlags::Canceled);
185
186        // This flag isn't in the specification, but we need to unset it anyway.
187        self.unset_flags(EventFlags::Handled);
188
189        // Step 3. Set event’s isTrusted attribute to false.
190        self.is_trusted.set(false);
191
192        // Step 4. Set event’s target to null.
193        self.target.set(None);
194
195        // Step 5. Set event’s type attribute to type.
196        *self.type_.borrow_mut() = type_;
197
198        // Step 6. Set event’s bubbles attribute to bubbles.
199        self.bubbles.set(bubbles);
200
201        // Step 7. Set event’s cancelable attribute to cancelable.
202        self.cancelable.set(cancelable);
203    }
204
205    fn set_flags(&self, flags_to_set: EventFlags) {
206        self.flags.set(self.flags.get().union(flags_to_set))
207    }
208
209    fn unset_flags(&self, flags_to_unset: EventFlags) {
210        let mut flags = self.flags.get();
211        flags.remove(flags_to_unset);
212        self.flags.set(flags);
213    }
214
215    fn has_flag(&self, flag: EventFlags) -> bool {
216        self.flags.get().contains(flag)
217    }
218
219    pub(crate) fn set_target(&self, target_: Option<&EventTarget>) {
220        self.target.set(target_);
221    }
222
223    pub(crate) fn set_related_target(&self, related_target: Option<&EventTarget>) {
224        self.related_target.set(related_target);
225    }
226
227    pub(crate) fn related_target(&self) -> Option<DomRoot<EventTarget>> {
228        self.related_target.get()
229    }
230
231    fn set_in_passive_listener(&self, value: bool) {
232        if value {
233            self.set_flags(EventFlags::InPassiveListener);
234        } else {
235            self.unset_flags(EventFlags::InPassiveListener);
236        }
237    }
238
239    /// <https://dom.spec.whatwg.org/#concept-event-path-append>
240    #[cfg_attr(crown, expect(crown::unrooted_must_root))]
241    pub(crate) fn append_to_path(
242        &self,
243        invocation_target: &EventTarget,
244        shadow_adjusted_target: Option<&EventTarget>,
245        related_target: Option<&EventTarget>,
246        slot_in_closed_tree: bool,
247    ) {
248        // Step 1. Let invocationTargetInShadowTree be false.
249        let mut invocation_target_in_shadow_tree = false;
250
251        // Step 2. If invocationTarget is a node and its root is a shadow root,
252        // then set invocationTargetInShadowTree to true.
253        if invocation_target
254            .downcast::<Node>()
255            .is_some_and(Node::is_in_a_shadow_tree)
256        {
257            invocation_target_in_shadow_tree = true;
258        }
259
260        // Step 3. Let root-of-closed-tree be false.
261        let mut root_of_closed_tree = false;
262
263        // Step 4. If invocationTarget is a shadow root whose mode is "closed", then set root-of-closed-tree to true.
264        if invocation_target
265            .downcast::<ShadowRoot>()
266            .is_some_and(|shadow_root| shadow_root.Mode() == ShadowRootMode::Closed)
267        {
268            root_of_closed_tree = true;
269        }
270
271        // Step 5. Append a new struct to event’s path whose invocation target is invocationTarget,
272        // invocation-target-in-shadow-tree is invocationTargetInShadowTree, shadow-adjusted target is
273        // shadowAdjustedTarget, relatedTarget is relatedTarget, touch target list is touchTargets,
274        // root-of-closed-tree is root-of-closed-tree, and slot-in-closed-tree is slot-in-closed-tree.
275        let event_path_segment = EventPathSegment {
276            invocation_target: Dom::from_ref(invocation_target),
277            shadow_adjusted_target: shadow_adjusted_target.map(Dom::from_ref),
278            related_target: related_target.map(Dom::from_ref),
279            invocation_target_in_shadow_tree,
280            root_of_closed_tree,
281            slot_in_closed_tree,
282        };
283        self.path.borrow_mut().push(event_path_segment);
284    }
285
286    /// <https://dom.spec.whatwg.org/#concept-event-dispatch>
287    pub(crate) fn dispatch(
288        &self,
289        target: &EventTarget,
290        legacy_target_override: bool,
291        can_gc: CanGc,
292        // TODO legacy_did_output_listeners_throw_flag for indexeddb
293    ) -> bool {
294        // > When a user interaction causes firing of an activation triggering input event in a Document document, the user agent
295        // > must perform the following activation notification steps before dispatching the event:
296        // <https://html.spec.whatwg.org/multipage/#user-activation-processing-model>
297        if self.is_an_activation_triggering_input_event() {
298            // TODO: it is not quite clear what does the spec mean by in a `Document`. https://github.com/whatwg/html/issues/12126
299            if let Some(document) = target.downcast::<Node>().map(|node| node.owner_doc()) {
300                UserActivation::handle_user_activation_notification(&document);
301            }
302        }
303
304        let mut target = DomRoot::from_ref(target);
305
306        // Step 1. Set event’s dispatch flag.
307        self.set_flags(EventFlags::Dispatch);
308
309        // Step 2. Let targetOverride be target, if legacy target override flag is not given,
310        // and target’s associated Document otherwise.
311        let target_override_document; // upcasted EventTarget's lifetime depends on this
312        let target_override = if legacy_target_override {
313            target_override_document = target
314                .downcast::<Window>()
315                .expect("legacy_target_override must be true only when target is a Window")
316                .Document();
317            DomRoot::from_ref(target_override_document.upcast::<EventTarget>())
318        } else {
319            target.clone()
320        };
321
322        // Step 3. Let activationTarget be null.
323        let mut activation_target = None;
324
325        // Step 4. Let relatedTarget be the result of retargeting event’s relatedTarget against target.
326        let related_target = self
327            .related_target
328            .get()
329            .map(|related_target| related_target.retarget(&target));
330
331        // Step 5. Let clearTargets be false.
332        let mut clear_targets = false;
333
334        // Step 6. If target is not relatedTarget or target is event’s relatedTarget:
335        let mut pre_activation_result: Option<InputActivationState> = None;
336        if related_target.as_ref() != Some(&target) ||
337            self.related_target.get().as_ref() == Some(&target)
338        {
339            // Step 6.1. Let touchTargets be a new list.
340            // TODO
341
342            // Step 6.2. For each touchTarget of event’s touch target list, append the result of retargeting
343            // TODO
344
345            // touchTarget against target to touchTargets.
346
347            // Step 6.3. Append to an event path with event, target, targetOverride, relatedTarget,
348            // touchTargets, and false.
349            self.append_to_path(
350                &target,
351                Some(target_override.upcast::<EventTarget>()),
352                related_target.as_deref(),
353                false,
354            );
355
356            // Step 6.4. Let isActivationEvent be true, if event is a MouseEvent object and
357            // event’s type attribute is "click"; otherwise false.
358            let is_activation_event = self.is::<MouseEvent>() && self.type_() == atom!("click");
359
360            // Step 6.5. If isActivationEvent is true and target has activation behavior,
361            // then set activationTarget to target.
362            if is_activation_event {
363                if let Some(element) = target.downcast::<Element>() {
364                    if element.as_maybe_activatable().is_some() {
365                        activation_target = Some(DomRoot::from_ref(element));
366                    }
367                }
368            }
369
370            // Step 6.6. Let slottable be target, if target is a slottable and is assigned, and null otherwise.
371            let mut slottable = if target
372                .downcast::<Node>()
373                .and_then(Node::assigned_slot)
374                .is_some()
375            {
376                Some(target.clone())
377            } else {
378                None
379            };
380
381            // Step 6.7. Let slot-in-closed-tree be false
382            let mut slot_in_closed_tree = false;
383
384            // Step 6.8. Let parent be the result of invoking target’s get the parent with event.
385            let mut parent_or_none = target.get_the_parent(self);
386            let mut done = false;
387
388            // Step 6.9. While parent is non-null:
389            while let Some(parent) = parent_or_none.clone() {
390                // Step 6.9.1. If slottable is non-null:
391                if slottable.is_some() {
392                    // Step 6.9.1.1. Assert: parent is a slot.
393                    let slot = parent
394                        .downcast::<HTMLSlotElement>()
395                        .expect("parent of slottable is not a slot");
396
397                    // Step 6.9.1.2. Set slottable to null.
398                    slottable = None;
399
400                    // Step 6.9.1.3. If parent’s root is a shadow root whose mode is "closed",
401                    // then set slot-in-closed-tree to true.
402                    if slot
403                        .containing_shadow_root()
404                        .is_some_and(|root| root.Mode() == ShadowRootMode::Closed)
405                    {
406                        slot_in_closed_tree = true;
407                    }
408                }
409
410                // Step 6.9.2. If parent is a slottable and is assigned, then set slottable to parent.
411                if parent
412                    .downcast::<Node>()
413                    .and_then(Node::assigned_slot)
414                    .is_some()
415                {
416                    slottable = Some(parent.clone());
417                }
418
419                // Step 6.9.3. Let relatedTarget be the result of retargeting event’s relatedTarget against parent.
420                let related_target = self
421                    .related_target
422                    .get()
423                    .map(|related_target| related_target.retarget(&parent));
424
425                // Step 6.9.4. Let touchTargets be a new list.
426                // TODO
427
428                // Step 6.9.5. For each touchTarget of event’s touch target list, append the result of retargeting
429                // touchTarget against parent to touchTargets.
430                // TODO
431
432                // Step 6.9.6. If parent is a Window object, or parent is a node and target’s root is a
433                // shadow-including inclusive ancestor of parent:
434                let root_is_shadow_inclusive_ancestor = parent
435                    .downcast::<Node>()
436                    .zip(target.downcast::<Node>())
437                    .is_some_and(|(parent, target)| {
438                        target
439                            .GetRootNode(&GetRootNodeOptions::empty())
440                            .is_shadow_including_inclusive_ancestor_of(parent)
441                    });
442                if parent.is::<Window>() || root_is_shadow_inclusive_ancestor {
443                    // Step 6.9.6.1. If isActivationEvent is true, event’s bubbles attribute is true, activationTarget
444                    // is null, and parent has activation behavior, then set activationTarget to parent.
445                    if is_activation_event && activation_target.is_none() && self.bubbles.get() {
446                        if let Some(element) = parent.downcast::<Element>() {
447                            if element.as_maybe_activatable().is_some() {
448                                activation_target = Some(DomRoot::from_ref(element));
449                            }
450                        }
451                    }
452
453                    // Step 6.9.6.2. Append to an event path with event, parent, null, relatedTarget, touchTargets,
454                    // and slot-in-closed-tree.
455                    self.append_to_path(
456                        &parent,
457                        None,
458                        related_target.as_deref(),
459                        slot_in_closed_tree,
460                    );
461                }
462                // Step 6.9.7. Otherwise, if parent is relatedTarget, then set parent to null.
463                else if Some(&parent) == related_target.as_ref() {
464                    // NOTE: This causes some lifetime shenanigans. Instead of making things complicated,
465                    // we just remember to treat parent as null later
466                    done = true;
467                }
468                // Step 6.9.8. Otherwise:
469                else {
470                    // Step 6.9.8.1. Set target to parent.
471                    target = parent.clone();
472
473                    // Step 6.9.8.2. If isActivationEvent is true, activationTarget is null, and target has
474                    // activation behavior, then set activationTarget to target.
475                    if is_activation_event && activation_target.is_none() {
476                        if let Some(element) = parent.downcast::<Element>() {
477                            if element.as_maybe_activatable().is_some() {
478                                activation_target = Some(DomRoot::from_ref(element));
479                            }
480                        }
481                    }
482
483                    // Step 6.9.8.3. Append to an event path with event, parent, target, relatedTarget,
484                    // touchTargets, and slot-in-closed-tree.
485                    self.append_to_path(
486                        &parent,
487                        Some(&target),
488                        related_target.as_deref(),
489                        slot_in_closed_tree,
490                    );
491                }
492
493                // Step 6.9.9. If parent is non-null, then set parent to the result of invoking parent’s
494                // get the parent with event
495                if !done {
496                    parent_or_none = parent.get_the_parent(self);
497                } else {
498                    parent_or_none = None;
499                }
500
501                // Step 6.9.10. Set slot-in-closed-tree to false.
502                slot_in_closed_tree = false;
503            }
504
505            // Step 6.10. Let clearTargetsStruct be the last struct in event’s path whose shadow-adjusted target
506            // is non-null.
507            // Step 6.11. Let clearTargets be true if clearTargetsStruct’s shadow-adjusted target,
508            // clearTargetsStruct’s relatedTarget, or an EventTarget object in clearTargetsStruct’s
509            // touch target list is a node and its root is a shadow root; otherwise false.
510            // TODO: Handle touch target list
511            clear_targets = self
512                .path
513                .borrow()
514                .iter()
515                .rev()
516                .find(|segment| segment.shadow_adjusted_target.is_some())
517                // This is "clearTargetsStruct"
518                .is_some_and(|clear_targets| {
519                    clear_targets
520                        .shadow_adjusted_target
521                        .as_ref()
522                        .and_then(|target| target.downcast::<Node>())
523                        .is_some_and(Node::is_in_a_shadow_tree) ||
524                        clear_targets
525                            .related_target
526                            .as_ref()
527                            .and_then(|target| target.downcast::<Node>())
528                            .is_some_and(Node::is_in_a_shadow_tree)
529                });
530
531            // Step 6.12. If activationTarget is non-null and activationTarget has legacy-pre-activation behavior,
532            // then run activationTarget’s legacy-pre-activation behavior.
533            if let Some(activation_target) = activation_target.as_ref() {
534                // Not specified in dispatch spec overtly; this is because
535                // the legacy canceled activation behavior of a checkbox
536                // or radio button needs to know what happened in the
537                // corresponding pre-activation behavior.
538                pre_activation_result = activation_target
539                    .as_maybe_activatable()
540                    .and_then(|activatable| activatable.legacy_pre_activation_behavior(can_gc));
541            }
542
543            let timeline_window = DomRoot::downcast::<Window>(target.global())
544                .filter(|window| window.need_emit_timeline_marker(TimelineMarkerType::DOMEvent));
545
546            // Step 6.13. For each struct in event’s path, in reverse order:
547            for (index, segment) in self.path.borrow().iter().enumerate().rev() {
548                // Step 6.13.1. If struct’s shadow-adjusted target is non-null, then set event’s
549                // eventPhase attribute to AT_TARGET.
550                if segment.shadow_adjusted_target.is_some() {
551                    self.phase.set(EventPhase::AtTarget);
552                }
553                // Step 6.13.2. Otherwise, set event’s eventPhase attribute to CAPTURING_PHASE.
554                else {
555                    self.phase.set(EventPhase::Capturing);
556                }
557
558                // Step 6.13.3. Invoke with struct, event, "capturing", and legacyOutputDidListenersThrowFlag if given.
559                invoke(
560                    segment,
561                    index,
562                    self,
563                    ListenerPhase::Capturing,
564                    timeline_window.as_deref(),
565                    can_gc,
566                )
567            }
568
569            // Step 6.14. For each struct in event’s path:
570            for (index, segment) in self.path.borrow().iter().enumerate() {
571                // Step 6.14.1. If struct’s shadow-adjusted target is non-null, then set event’s
572                // eventPhase attribute to AT_TARGET.
573                if segment.shadow_adjusted_target.is_some() {
574                    self.phase.set(EventPhase::AtTarget);
575                }
576                // Step 6.14.2. Otherwise:
577                else {
578                    // Step 6.14.2.1. If event’s bubbles attribute is false, then continue.
579                    if !self.bubbles.get() {
580                        continue;
581                    }
582
583                    // Step 6.14.2.2. Set event’s eventPhase attribute to BUBBLING_PHASE.
584                    self.phase.set(EventPhase::Bubbling);
585                }
586
587                // Step 6.14.3. Invoke with struct, event, "bubbling", and legacyOutputDidListenersThrowFlag if given.
588                invoke(
589                    segment,
590                    index,
591                    self,
592                    ListenerPhase::Bubbling,
593                    timeline_window.as_deref(),
594                    can_gc,
595                );
596            }
597        }
598
599        // Step 7. Set event’s eventPhase attribute to NONE.
600        self.phase.set(EventPhase::None);
601
602        // FIXME: The UIEvents spec still expects firing an event
603        // to carry a "default action" semantic, but the HTML spec
604        // has removed this concept. Nothing in either spec currently
605        // (as of Jan 11 2020) says that, e.g., a keydown event on an
606        // input element causes a character to be typed; the UIEvents
607        // spec assumes the HTML spec is covering it, and the HTML spec
608        // no longer specifies any UI event other than mouse click as
609        // causing an element to perform an action.
610        // Compare:
611        // https://w3c.github.io/uievents/#default-action
612        // https://dom.spec.whatwg.org/#action-versus-occurance
613        if !self.DefaultPrevented() {
614            if let Some(target) = self.GetTarget() {
615                if let Some(node) = target.downcast::<Node>() {
616                    let vtable = vtable_for(node);
617                    vtable.handle_event(self, can_gc);
618                }
619            }
620        }
621
622        // Step 8. Set event’s currentTarget attribute to null.
623        self.current_target.set(None);
624
625        // Step 9. Set event’s path to the empty list.
626        self.path.borrow_mut().clear();
627
628        // Step 10. Unset event’s dispatch flag, stop propagation flag, and stop immediate propagation flag.
629        self.unset_flags(EventFlags::Dispatch);
630        self.unset_flags(EventFlags::StopPropagation);
631        self.unset_flags(EventFlags::StopImmediatePropagation);
632
633        // Step 11. If clearTargets is true:
634        if clear_targets {
635            // Step 11.1. Set event’s target to null.
636            self.target.set(None);
637
638            // Step 11.2. Set event’s relatedTarget to null.
639            self.related_target.set(None);
640
641            // Step 11.3. Set event’s touch target list to the empty list.
642            // TODO
643        }
644
645        // Step 12. If activationTarget is non-null:
646        if let Some(activation_target) = activation_target {
647            // NOTE: The activation target may have been disabled by an event handler
648            if let Some(activatable) = activation_target.as_maybe_activatable() {
649                // Step 12.1. If event’s canceled flag is unset, then run activationTarget’s
650                // activation behavior with event.
651                if !self.DefaultPrevented() {
652                    activatable.activation_behavior(self, &target, can_gc);
653                }
654                // Step 12.2. Otherwise, if activationTarget has legacy-canceled-activation behavior, then run
655                // activationTarget’s legacy-canceled-activation behavior.
656                else {
657                    activatable.legacy_canceled_activation_behavior(pre_activation_result, can_gc);
658                }
659            }
660        }
661
662        // Step 13. Return false if event’s canceled flag is set; otherwise true.
663        !self.DefaultPrevented()
664    }
665
666    #[inline]
667    pub(crate) fn dispatching(&self) -> bool {
668        self.has_flag(EventFlags::Dispatch)
669    }
670
671    #[inline]
672    pub(crate) fn initialized(&self) -> bool {
673        self.has_flag(EventFlags::Initialized)
674    }
675
676    #[inline]
677    pub(crate) fn type_(&self) -> Atom {
678        self.type_.borrow().clone()
679    }
680
681    #[inline]
682    pub(crate) fn mark_as_handled(&self) {
683        self.set_flags(EventFlags::Handled);
684    }
685
686    #[inline]
687    pub(crate) fn flags(&self) -> EventFlags {
688        self.flags.get()
689    }
690
691    pub(crate) fn set_trusted(&self, trusted: bool) {
692        self.is_trusted.set(trusted);
693    }
694
695    pub(crate) fn set_composed(&self, composed: bool) {
696        if composed {
697            self.set_flags(EventFlags::Composed);
698        } else {
699            self.unset_flags(EventFlags::Composed);
700        }
701    }
702
703    /// <https://html.spec.whatwg.org/multipage/#activation-triggering-input-event>
704    fn is_an_activation_triggering_input_event(&self) -> bool {
705        // > An activation triggering input event is any event whose isTrusted attribute is true ..
706        if !self.is_trusted.get() {
707            return false;
708        }
709
710        // > and whose type is one of:
711        let event_type = self.Type();
712        match_domstring_ascii!(event_type,
713            // > - "keydown", provided the key is neither the Esc key nor a shortcut key reserved by the user agent;
714            "keydown" => self.downcast::<KeyboardEvent>().expect("`Event` with type `keydown` should be a `KeyboardEvent` interface").key() != Key::Named(NamedKey::Escape),
715            // > - "mousedown";
716            "mousedown" => true,
717            // > - "pointerdown", provided the event's pointerType is "mouse";
718            "pointerdown" => self.downcast::<PointerEvent>().expect("`Event` with type `pointerdown` should be a `PointerEvent` interface").PointerType().eq("mouse"),
719            // > - "pointerup", provided the event's pointerType is not "mouse"; or
720            "pointerup" => !self.downcast::<PointerEvent>().expect("`Event` with type `pointerup` should be a `PointerEvent` interface").PointerType().eq("mouse"),
721            // > - "touchend".
722            "touchend" => true,
723            _ => false,
724        )
725    }
726
727    /// <https://dom.spec.whatwg.org/#firing-events>
728    pub(crate) fn fire(&self, target: &EventTarget, can_gc: CanGc) -> bool {
729        self.set_trusted(true);
730
731        target.dispatch_event(self, can_gc)
732    }
733
734    /// <https://dom.spec.whatwg.org/#inner-event-creation-steps>
735    fn inner_creation_steps(
736        global: &GlobalScope,
737        proto: Option<HandleObject>,
738        init: &EventBinding::EventInit,
739        can_gc: CanGc,
740    ) -> DomRoot<Event> {
741        // Step 1. Let event be the result of creating a new object using eventInterface.
742        // If realm is non-null, then use that realm; otherwise, use the default behavior defined in Web IDL.
743        let event = Event::new_uninitialized_with_proto(global, proto, can_gc);
744
745        // Step 2. Set event’s initialized flag.
746        event.set_flags(EventFlags::Initialized);
747
748        // Step 3. Initialize event’s timeStamp attribute to the relative high resolution
749        // coarse time given time and event’s relevant global object.
750        // NOTE: This is done inside Event::new_inherited
751
752        // Step 3. For each member → value in dictionary, if event has an attribute whose
753        // identifier is member, then initialize that attribute to value.#
754        event.bubbles.set(init.bubbles);
755        event.cancelable.set(init.cancelable);
756        event.set_composed(init.composed);
757
758        // Step 5. Run the event constructing steps with event and dictionary.
759        // NOTE: Event construction steps may be defined by subclasses
760
761        // Step 6. Return event.
762        event
763    }
764
765    /// Implements the logic behind the [get the parent](https://dom.spec.whatwg.org/#get-the-parent)
766    /// algorithm for shadow roots.
767    pub(crate) fn should_pass_shadow_boundary(&self, shadow_root: &ShadowRoot) -> bool {
768        debug_assert!(self.dispatching());
769
770        // > A shadow root’s get the parent algorithm, given an event, returns null if event’s composed flag
771        // > is unset and shadow root is the root of event’s path’s first struct’s invocation target;
772        // > otherwise shadow root’s host.
773        if self.Composed() {
774            return true;
775        }
776
777        let path = self.path.borrow();
778        let first_invocation_target = &path
779            .first()
780            .expect("Event path is empty despite event currently being dispatched")
781            .invocation_target
782            .as_rooted();
783
784        // The spec doesn't tell us what should happen if the invocation target is not a node
785        let Some(target_node) = first_invocation_target.downcast::<Node>() else {
786            return false;
787        };
788
789        &*target_node.GetRootNode(&GetRootNodeOptions::empty()) != shadow_root.upcast::<Node>()
790    }
791
792    /// <https://dom.spec.whatwg.org/#set-the-canceled-flag>
793    fn set_the_cancelled_flag(&self) {
794        if self.cancelable.get() && !self.has_flag(EventFlags::InPassiveListener) {
795            self.set_flags(EventFlags::Canceled);
796        }
797    }
798}
799
800impl EventMethods<crate::DomTypeHolder> for Event {
801    /// <https://dom.spec.whatwg.org/#concept-event-constructor>
802    fn Constructor(
803        global: &GlobalScope,
804        proto: Option<HandleObject>,
805        can_gc: CanGc,
806        type_: DOMString,
807        init: &EventBinding::EventInit,
808    ) -> Fallible<DomRoot<Event>> {
809        // Step 1. Let event be the result of running the inner event creation steps with
810        // this interface, null, now, and eventInitDict.
811        let event = Event::inner_creation_steps(global, proto, init, can_gc);
812
813        // Step 2. Initialize event’s type attribute to type.
814        *event.type_.borrow_mut() = Atom::from(type_);
815
816        // Step 3. Return event.
817        Ok(event)
818    }
819
820    /// <https://dom.spec.whatwg.org/#dom-event-eventphase>
821    fn EventPhase(&self) -> u16 {
822        self.phase.get() as u16
823    }
824
825    /// <https://dom.spec.whatwg.org/#dom-event-type>
826    fn Type(&self) -> DOMString {
827        DOMString::from(&*self.type_()) // FIXME(ajeffrey): Directly convert from Atom to DOMString
828    }
829
830    /// <https://dom.spec.whatwg.org/#dom-event-target>
831    fn GetTarget(&self) -> Option<DomRoot<EventTarget>> {
832        self.target.get()
833    }
834
835    /// <https://dom.spec.whatwg.org/#dom-event-srcelement>
836    fn GetSrcElement(&self) -> Option<DomRoot<EventTarget>> {
837        self.target.get()
838    }
839
840    /// <https://dom.spec.whatwg.org/#dom-event-currenttarget>
841    fn GetCurrentTarget(&self) -> Option<DomRoot<EventTarget>> {
842        self.current_target.get()
843    }
844
845    /// <https://dom.spec.whatwg.org/#dom-event-composedpath>
846    fn ComposedPath(&self) -> Vec<DomRoot<EventTarget>> {
847        // Step 1. Let composedPath be an empty list.
848        let mut composed_path = vec![];
849
850        // Step 2. Let path be this’s path.
851        let path = self.path.borrow();
852
853        // Step 3. If path is empty, then return composedPath.
854        if path.is_empty() {
855            return composed_path;
856        }
857
858        // Step 4. Let currentTarget be this’s currentTarget attribute value.
859        let current_target = self.GetCurrentTarget();
860
861        // Step 5. Append currentTarget to composedPath.
862        // TODO: https://github.com/whatwg/dom/issues/1343
863        composed_path.push(current_target.clone().expect(
864            "Since the event's path is not empty it is being dispatched and must have a current target",
865        ));
866
867        // Step 6. Let currentTargetIndex be 0.
868        let mut current_target_index = 0;
869
870        // Step 7. Let currentTargetHiddenSubtreeLevel be 0.
871        let mut current_target_hidden_subtree_level = 0;
872
873        // Step 8. Let index be path’s size − 1.
874        // Step 9. While index is greater than or equal to 0:
875        // NOTE: This is just iterating the path in reverse
876        for (index, element) in path.iter().enumerate().rev() {
877            // Step 9.1 If path[index]'s root-of-closed-tree is true, then increase
878            // currentTargetHiddenSubtreeLevel by 1.
879            if element.root_of_closed_tree {
880                current_target_hidden_subtree_level += 1;
881            }
882
883            // Step 9.2 If path[index]'s invocation target is currentTarget, then set
884            // currentTargetIndex to index and break.
885            if current_target
886                .as_ref()
887                .is_some_and(|target| target.as_traced() == element.invocation_target)
888            {
889                current_target_index = index;
890                break;
891            }
892
893            // Step 9.3 If path[index]'s slot-in-closed-tree is true, then decrease
894            // currentTargetHiddenSubtreeLevel by 1.
895            if element.slot_in_closed_tree {
896                current_target_hidden_subtree_level -= 1;
897            }
898
899            // Step 9.4 Decrease index by 1.
900        }
901
902        // Step 10. Let currentHiddenLevel and maxHiddenLevel be currentTargetHiddenSubtreeLevel.
903        let mut current_hidden_level = current_target_hidden_subtree_level;
904        let mut max_hidden_level = current_target_hidden_subtree_level;
905
906        // Step 11. Set index to currentTargetIndex − 1.
907        // Step 12. While index is greater than or equal to 0:
908        // NOTE: This is just iterating part of the path in reverse
909        for element in path.iter().take(current_target_index).rev() {
910            // Step 12.1 If path[index]'s root-of-closed-tree is true, then increase currentHiddenLevel by 1.
911            if element.root_of_closed_tree {
912                current_hidden_level += 1;
913            }
914
915            // Step 12.2 If currentHiddenLevel is less than or equal to maxHiddenLevel,
916            // then prepend path[index]'s invocation target to composedPath.
917            if current_hidden_level <= max_hidden_level {
918                composed_path.insert(0, element.invocation_target.as_rooted());
919            }
920
921            // Step 12.3 If path[index]'s slot-in-closed-tree is true:
922            if element.slot_in_closed_tree {
923                // Step 12.3.1 Decrease currentHiddenLevel by 1.
924                current_hidden_level -= 1;
925
926                // Step 12.3.2 If currentHiddenLevel is less than maxHiddenLevel, then set
927                // maxHiddenLevel to currentHiddenLevel.
928                if current_hidden_level < max_hidden_level {
929                    max_hidden_level = current_hidden_level;
930                }
931            }
932
933            // Step 12.4 Decrease index by 1.
934        }
935
936        // Step 13. Set currentHiddenLevel and maxHiddenLevel to currentTargetHiddenSubtreeLevel.
937        current_hidden_level = current_target_hidden_subtree_level;
938        max_hidden_level = current_target_hidden_subtree_level;
939
940        // Step 14. Set index to currentTargetIndex + 1.
941        // Step 15. While index is less than path’s size:
942        // NOTE: This is just iterating the list and skipping the first current_target_index + 1 elements
943        //       (The +1 is necessary because the index is 0-based and the skip method is not)
944        for element in path.iter().skip(current_target_index + 1) {
945            // Step 15.1 If path[index]'s slot-in-closed-tree is true, then increase currentHiddenLevel by 1.
946            if element.slot_in_closed_tree {
947                current_hidden_level += 1;
948            }
949
950            // Step 15.2 If currentHiddenLevel is less than or equal to maxHiddenLevel,
951            // then append path[index]'s invocation target to composedPath.
952            if current_hidden_level <= max_hidden_level {
953                composed_path.push(element.invocation_target.as_rooted());
954            }
955
956            // Step 15.3 If path[index]'s root-of-closed-tree is true:
957            if element.root_of_closed_tree {
958                // Step 15.3.1 Decrease currentHiddenLevel by 1.
959                current_hidden_level -= 1;
960
961                // Step 15.3.2 If currentHiddenLevel is less than maxHiddenLevel, then set
962                // maxHiddenLevel to currentHiddenLevel.
963                if current_hidden_level < max_hidden_level {
964                    max_hidden_level = current_hidden_level;
965                }
966            }
967
968            // Step 15.4 Increase index by 1.
969        }
970
971        // Step 16. Return composedPath.
972        composed_path
973    }
974
975    /// <https://dom.spec.whatwg.org/#dom-event-defaultprevented>
976    fn DefaultPrevented(&self) -> bool {
977        self.has_flag(EventFlags::Canceled)
978    }
979
980    /// <https://dom.spec.whatwg.org/#dom-event-composed>
981    fn Composed(&self) -> bool {
982        self.has_flag(EventFlags::Composed)
983    }
984
985    /// <https://dom.spec.whatwg.org/#dom-event-preventdefault>
986    fn PreventDefault(&self) {
987        self.set_the_cancelled_flag();
988    }
989
990    /// <https://dom.spec.whatwg.org/#dom-event-stoppropagation>
991    fn StopPropagation(&self) {
992        self.set_flags(EventFlags::StopPropagation);
993    }
994
995    /// <https://dom.spec.whatwg.org/#dom-event-stopimmediatepropagation>
996    fn StopImmediatePropagation(&self) {
997        self.set_flags(EventFlags::StopPropagation | EventFlags::StopImmediatePropagation);
998    }
999
1000    /// <https://dom.spec.whatwg.org/#dom-event-bubbles>
1001    fn Bubbles(&self) -> bool {
1002        self.bubbles.get()
1003    }
1004
1005    /// <https://dom.spec.whatwg.org/#dom-event-cancelable>
1006    fn Cancelable(&self) -> bool {
1007        self.cancelable.get()
1008    }
1009
1010    /// <https://dom.spec.whatwg.org/#dom-event-returnvalue>
1011    fn ReturnValue(&self) -> bool {
1012        !self.has_flag(EventFlags::Canceled)
1013    }
1014
1015    /// <https://dom.spec.whatwg.org/#dom-event-returnvalue>
1016    fn SetReturnValue(&self, val: bool) {
1017        if !val {
1018            self.set_the_cancelled_flag();
1019        }
1020    }
1021
1022    /// <https://dom.spec.whatwg.org/#dom-event-cancelbubble>
1023    fn CancelBubble(&self) -> bool {
1024        self.has_flag(EventFlags::StopPropagation)
1025    }
1026
1027    /// <https://dom.spec.whatwg.org/#dom-event-cancelbubble>
1028    fn SetCancelBubble(&self, value: bool) {
1029        if value {
1030            self.set_flags(EventFlags::StopPropagation);
1031        }
1032    }
1033
1034    /// <https://dom.spec.whatwg.org/#dom-event-timestamp>
1035    fn TimeStamp(&self) -> DOMHighResTimeStamp {
1036        self.global()
1037            .performance()
1038            .to_dom_high_res_time_stamp(self.time_stamp)
1039    }
1040
1041    /// <https://dom.spec.whatwg.org/#dom-event-initevent>
1042    fn InitEvent(&self, type_: DOMString, bubbles: bool, cancelable: bool) {
1043        self.init_event(Atom::from(type_), bubbles, cancelable)
1044    }
1045
1046    /// <https://dom.spec.whatwg.org/#dom-event-istrusted>
1047    fn IsTrusted(&self) -> bool {
1048        self.is_trusted.get()
1049    }
1050}
1051
1052#[derive(Clone, Copy, MallocSizeOf, PartialEq)]
1053pub(crate) enum EventBubbles {
1054    Bubbles,
1055    DoesNotBubble,
1056}
1057
1058impl From<bool> for EventBubbles {
1059    fn from(boolean: bool) -> Self {
1060        if boolean {
1061            EventBubbles::Bubbles
1062        } else {
1063            EventBubbles::DoesNotBubble
1064        }
1065    }
1066}
1067
1068impl From<EventBubbles> for bool {
1069    fn from(bubbles: EventBubbles) -> Self {
1070        match bubbles {
1071            EventBubbles::Bubbles => true,
1072            EventBubbles::DoesNotBubble => false,
1073        }
1074    }
1075}
1076
1077#[derive(Clone, Copy, MallocSizeOf, PartialEq)]
1078pub(crate) enum EventCancelable {
1079    Cancelable,
1080    NotCancelable,
1081}
1082
1083impl From<bool> for EventCancelable {
1084    fn from(boolean: bool) -> Self {
1085        if boolean {
1086            EventCancelable::Cancelable
1087        } else {
1088            EventCancelable::NotCancelable
1089        }
1090    }
1091}
1092
1093impl From<EventCancelable> for bool {
1094    fn from(cancelable: EventCancelable) -> Self {
1095        match cancelable {
1096            EventCancelable::Cancelable => true,
1097            EventCancelable::NotCancelable => false,
1098        }
1099    }
1100}
1101
1102#[derive(Clone, Copy, MallocSizeOf, PartialEq)]
1103pub(crate) enum EventComposed {
1104    Composed,
1105    NotComposed,
1106}
1107
1108impl From<bool> for EventComposed {
1109    fn from(boolean: bool) -> Self {
1110        if boolean {
1111            EventComposed::Composed
1112        } else {
1113            EventComposed::NotComposed
1114        }
1115    }
1116}
1117
1118impl From<EventComposed> for bool {
1119    fn from(composed: EventComposed) -> Self {
1120        match composed {
1121            EventComposed::Composed => true,
1122            EventComposed::NotComposed => false,
1123        }
1124    }
1125}
1126
1127#[derive(Clone, Copy, Debug, Eq, JSTraceable, PartialEq)]
1128#[repr(u16)]
1129#[derive(MallocSizeOf)]
1130pub(crate) enum EventPhase {
1131    None = EventConstants::NONE,
1132    Capturing = EventConstants::CAPTURING_PHASE,
1133    AtTarget = EventConstants::AT_TARGET,
1134    Bubbling = EventConstants::BUBBLING_PHASE,
1135}
1136
1137/// [`EventFlags`] tracks which specification-defined flags in an [`Event`] are enabled.
1138#[derive(Clone, Copy, JSTraceable, MallocSizeOf, PartialEq)]
1139pub(crate) struct EventFlags(u8);
1140
1141bitflags! {
1142    impl EventFlags: u8 {
1143        /// <https://dom.spec.whatwg.org/#canceled-flag>
1144        const Canceled = 1 << 0;
1145        /// <https://dom.spec.whatwg.org/#composed-flag>
1146        const Composed = 1 << 1;
1147        /// <https://dom.spec.whatwg.org/#dispatch-flag>
1148        const Dispatch =  1 << 2;
1149        /// The event has been handled somewhere in the DOM, and it should be prevented from being
1150        /// re-handled elsewhere. This doesn't affect the judgement of `DefaultPrevented`
1151        const Handled =  1 << 3;
1152        /// <https://dom.spec.whatwg.org/#in-passive-listener-flag>
1153        const InPassiveListener =  1 << 4;
1154        /// <https://dom.spec.whatwg.org/#initialized-flag>
1155        const Initialized =  1 << 5;
1156        /// <https://dom.spec.whatwg.org/#stop-propagation-flag>
1157        const StopPropagation = 1 << 6;
1158        /// <https://dom.spec.whatwg.org/#stop-immediate-propagation-flag>
1159        const StopImmediatePropagation = 1 << 7;
1160    }
1161}
1162
1163impl From<EventFlags> for InputEventResult {
1164    fn from(event_flags: EventFlags) -> Self {
1165        let mut result = Self::default();
1166        if event_flags.contains(EventFlags::Canceled) {
1167            result |= Self::DefaultPrevented;
1168        }
1169        if event_flags.contains(EventFlags::Handled) {
1170            result |= Self::Consumed;
1171        }
1172        result
1173    }
1174}
1175
1176/// <https://dom.spec.whatwg.org/#concept-event-fire>
1177pub(crate) struct EventTask {
1178    pub(crate) target: Trusted<EventTarget>,
1179    pub(crate) name: Atom,
1180    pub(crate) bubbles: EventBubbles,
1181    pub(crate) cancelable: EventCancelable,
1182}
1183
1184impl TaskOnce for EventTask {
1185    fn run_once(self, cx: &mut js::context::JSContext) {
1186        let target = self.target.root();
1187        let bubbles = self.bubbles;
1188        let cancelable = self.cancelable;
1189        target.fire_event_with_params(
1190            self.name,
1191            bubbles,
1192            cancelable,
1193            EventComposed::NotComposed,
1194            CanGc::from_cx(cx),
1195        );
1196    }
1197}
1198
1199/// <https://html.spec.whatwg.org/multipage/#fire-a-simple-event>
1200pub(crate) struct SimpleEventTask {
1201    pub(crate) target: Trusted<EventTarget>,
1202    pub(crate) name: Atom,
1203}
1204
1205impl TaskOnce for SimpleEventTask {
1206    fn run_once(self, cx: &mut js::context::JSContext) {
1207        let target = self.target.root();
1208        target.fire_event(self.name, CanGc::from_cx(cx));
1209    }
1210}
1211
1212/// <https://dom.spec.whatwg.org/#concept-event-listener-invoke>
1213fn invoke(
1214    segment: &EventPathSegment,
1215    segment_index_in_path: usize,
1216    event: &Event,
1217    phase: ListenerPhase,
1218    timeline_window: Option<&Window>,
1219    can_gc: CanGc,
1220    // TODO legacy_output_did_listeners_throw for indexeddb
1221) {
1222    // Step 1. Set event’s target to the shadow-adjusted target of the last struct in event’s path,
1223    // that is either struct or preceding struct, whose shadow-adjusted target is non-null.
1224    event.target.set(
1225        event.path.borrow()[..segment_index_in_path + 1]
1226            .iter()
1227            .rev()
1228            .flat_map(|segment| segment.shadow_adjusted_target.clone())
1229            .next()
1230            .as_deref(),
1231    );
1232
1233    // Step 2. Set event’s relatedTarget to struct’s relatedTarget.
1234    event.related_target.set(segment.related_target.as_deref());
1235
1236    // TODO: Set event’s touch target list to struct’s touch target list.
1237
1238    // Step 4. If event’s stop propagation flag is set, then return.
1239    if event.has_flag(EventFlags::StopPropagation) {
1240        return;
1241    }
1242
1243    // Step 5. Initialize event’s currentTarget attribute to struct’s invocation target.
1244    event.current_target.set(Some(&segment.invocation_target));
1245
1246    // Step 6. Let listeners be a clone of event’s currentTarget attribute value’s event listener list.
1247    let listeners = segment.invocation_target.get_listeners_for(&event.type_());
1248
1249    // Step 7. Let invocationTargetInShadowTree be struct’s invocation-target-in-shadow-tree.
1250    let invocation_target_in_shadow_tree = segment.invocation_target_in_shadow_tree;
1251
1252    // Step 8. Let found be the result of running inner invoke with event, listeners, phase,
1253    // invocationTargetInShadowTree, and legacyOutputDidListenersThrowFlag if given.
1254    let found = inner_invoke(
1255        event,
1256        &listeners,
1257        phase,
1258        invocation_target_in_shadow_tree,
1259        timeline_window,
1260        can_gc,
1261    );
1262
1263    // Step 9. If found is false and event’s isTrusted attribute is true:
1264    if !found && event.is_trusted.get() {
1265        // Step 9.1 Let originalEventType be event’s type attribute value.
1266        let original_type = event.type_();
1267
1268        // Step 9.2 If event’s type attribute value is a match for any of the strings in the first column
1269        // in the following table, set event’s type attribute value to the string in the second column on
1270        // the same row as the matching string, and return otherwise.
1271        let legacy_type = match event.type_() {
1272            atom!("animationend") => atom!("webkitAnimationEnd"),
1273            atom!("animationiteration") => atom!("webkitAnimationIteration"),
1274            atom!("animationstart") => atom!("webkitAnimationStart"),
1275            atom!("transitionend") => atom!("webkitTransitionEnd"),
1276            atom!("transitionrun") => atom!("webkitTransitionRun"),
1277            _ => return,
1278        };
1279        *event.type_.borrow_mut() = legacy_type;
1280
1281        // Step 9.3 Inner invoke with event, listeners, phase, invocationTargetInShadowTree,
1282        // and legacyOutputDidListenersThrowFlag if given.
1283        inner_invoke(
1284            event,
1285            &listeners,
1286            phase,
1287            invocation_target_in_shadow_tree,
1288            timeline_window,
1289            can_gc,
1290        );
1291
1292        // Step 9.4 Set event’s type attribute value to originalEventType.
1293        *event.type_.borrow_mut() = original_type;
1294    }
1295}
1296
1297/// <https://dom.spec.whatwg.org/#concept-event-listener-inner-invoke>
1298fn inner_invoke(
1299    event: &Event,
1300    listeners: &EventListeners,
1301    phase: ListenerPhase,
1302    invocation_target_in_shadow_tree: bool,
1303    timeline_window: Option<&Window>,
1304    can_gc: CanGc,
1305) -> bool {
1306    // Step 1. Let found be false.
1307    let mut found = false;
1308
1309    // Step 2. For each listener in listeners, whose removed is false:
1310    for listener in listeners.iter() {
1311        if listener.borrow().removed() {
1312            continue;
1313        }
1314
1315        // Step 2.1 If event’s type attribute value is not listener’s type, then continue.
1316
1317        // Step 2.2. Set found to true.
1318        found = true;
1319
1320        // Step 2.3 If phase is "capturing" and listener’s capture is false, then continue.
1321        // Step 2.4 If phase is "bubbling" and listener’s capture is true, then continue.
1322        if listener.borrow().phase() != phase {
1323            continue;
1324        }
1325
1326        let event_target = event
1327            .GetCurrentTarget()
1328            .expect("event target was initialized as part of \"invoke\"");
1329
1330        // Step 2.5 If listener’s once is true, then remove an event listener given event’s currentTarget
1331        // attribute value and listener.
1332        if listener.borrow().once() {
1333            event_target.remove_listener(&event.type_(), listener);
1334        }
1335
1336        let Some(compiled_listener) =
1337            listener
1338                .borrow()
1339                .get_compiled_listener(&event_target, &event.type_(), can_gc)
1340        else {
1341            continue;
1342        };
1343
1344        // Step 2.6 Let global be listener callback’s associated realm’s global object.
1345        let global = compiled_listener.associated_global();
1346
1347        // Step 2.7 Let currentEvent be undefined.
1348        let mut current_event = None;
1349        // Step 2.8 If global is a Window object:
1350        if let Some(window) = global.downcast::<Window>() {
1351            // Step 2.8.1 Set currentEvent to global’s current event.
1352            current_event = window.current_event();
1353
1354            // Step 2.8.2 If invocationTargetInShadowTree is false, then set global’s current event to event.
1355            if !invocation_target_in_shadow_tree {
1356                current_event = window.set_current_event(Some(event))
1357            }
1358        }
1359
1360        // Step 2.9 If listener’s passive is true, then set event's in passive listener flag.
1361        event.set_in_passive_listener(event_target.is_passive(listener));
1362
1363        // Step 2.10 If global is a Window object, then record timing info for event listener
1364        // given event and listener.
1365        // Step 2.11 Call a user object’s operation with listener’s callback, "handleEvent", « event »,
1366        // and event’s currentTarget attribute value. If this throws an exception exception:
1367        //     Step 2.10.1 Report exception for listener’s callback’s corresponding JavaScript object’s
1368        //     associated realm’s global object.
1369        //     TODO Step 2.10.2 Set legacyOutputDidListenersThrowFlag if given.
1370        let marker = TimelineMarker::start("DOMEvent".to_owned());
1371        compiled_listener.call_or_handle_event(
1372            &event_target,
1373            event,
1374            ExceptionHandling::Report,
1375            can_gc,
1376        );
1377        if let Some(window) = timeline_window {
1378            window.emit_timeline_marker(marker.end());
1379        }
1380
1381        // Step 2.12 Unset event’s in passive listener flag.
1382        event.set_in_passive_listener(false);
1383
1384        // Step 2.13 If global is a Window object, then set global’s current event to currentEvent.
1385        if let Some(window) = global.downcast::<Window>() {
1386            window.set_current_event(current_event.as_deref());
1387        }
1388
1389        // Step 2.13: If event’s stop immediate propagation flag is set, then break.
1390        if event.has_flag(EventFlags::StopImmediatePropagation) {
1391            break;
1392        }
1393    }
1394
1395    // Step 3.
1396    found
1397}