Implement Clipboard Event Api (#33576)

* implement ClipboardEvent interface

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* draft implementation of clipboard events

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* handle received clipboard events inside html elemtents

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* use rustdoc style

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* fix compilation errors due to rebase

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* update arboard crate

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* improve paste events

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* code cleanup

revert arboard crate's update, handle text only

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* restrict visibility of some methods to script crate

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* propagate CanGc argument

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* simplify handle_clipboard_msg

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* remove code duplication

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* fix potential borrow hazard

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* add clipboard_event pref, restore unit test code

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* retrict visibility of some document's methods

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* check if clipboardevent is trusted

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* enable clipboardevent

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

* fix compilation for egl ports

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

---------

Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>

18 files changed, 550 insertions, 22 deletions

diff --git a/components/compositing/windowing.rs b/components/compositing/windowing.rs
index dce66be05ca..f2648246c2b 100644
--- a/components/compositing/windowing.rs
+++ b/components/compositing/windowing.rs
@@ -14,8 +14,8 @@ use keyboard_types::{CompositionEvent, KeyboardEvent};
 use libc::c_void;
 use net::protocols::ProtocolRegistry;
 use script_traits::{
-    GamepadEvent, MediaSessionActionType, MouseButton, Theme, TouchEventType, TouchId,
-    TraversalDirection, WheelDelta,
+    ClipboardEventType, GamepadEvent, MediaSessionActionType, MouseButton, Theme, TouchEventType,
+    TouchId, TraversalDirection, WheelDelta,
 };
 use servo_geometry::{DeviceIndependentIntRect, DeviceIndependentIntSize, DeviceIndependentPixel};
 use servo_url::ServoUrl;
@@ -134,6 +134,8 @@ pub enum EmbedderEvent {
     Gamepad(GamepadEvent),
     /// Vertical Synchronization tick
     Vsync,
+    /// Sent when access to clipboard is required
+    ClipboardAction(ClipboardEventType),
 }
 
 impl Debug for EmbedderEvent {
@@ -196,6 +198,7 @@ impl Debug for EmbedderEvent {
             EmbedderEvent::ReplaceNativeSurface(..) => write!(f, "ReplaceNativeSurface"),
             EmbedderEvent::Gamepad(..) => write!(f, "Gamepad"),
             EmbedderEvent::Vsync => write!(f, "Vsync"),
+            EmbedderEvent::ClipboardAction(_) => write!(f, "ClipboardAction"),
         }
     }
 }
diff --git a/components/config/prefs.rs b/components/config/prefs.rs
index 9c4edf30e3a..1561198f281 100644
--- a/components/config/prefs.rs
+++ b/components/config/prefs.rs
@@ -75,6 +75,7 @@ pub struct Preferences {
     pub dom_allow_scripts_to_close_windows: bool,
     pub dom_canvas_capture_enabled: bool,
     pub dom_canvas_text_enabled: bool,
+    pub dom_clipboardevent_enabled: bool,
     pub dom_composition_event_enabled: bool,
     pub dom_crypto_subtle_enabled: bool,
     pub dom_customelements_enabled: bool,
@@ -236,6 +237,7 @@ impl Preferences {
             dom_bluetooth_testing_enabled: false,
             dom_canvas_capture_enabled: false,
             dom_canvas_text_enabled: true,
+            dom_clipboardevent_enabled: true,
             dom_composition_event_enabled: false,
             dom_crypto_subtle_enabled: true,
             dom_customelements_enabled: true,
diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index 0558c234f51..50932dbad9d 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -138,13 +138,13 @@ use script_layout_interface::{LayoutFactory, ScriptThreadFactory};
 use script_traits::CompositorEvent::{MouseButtonEvent, MouseMoveEvent};
 use script_traits::{
     webdriver_msg, AnimationState, AnimationTickType, AuxiliaryBrowsingContextLoadInfo,
-    BroadcastMsg, CompositorEvent, ConstellationControlMsg, DiscardBrowsingContext,
-    DocumentActivity, DocumentState, GamepadEvent, IFrameLoadInfo, IFrameLoadInfoWithData,
-    IFrameSandboxState, IFrameSizeMsg, Job, LayoutMsg as FromLayoutMsg, LoadData, LoadOrigin,
-    LogEntry, MediaSessionActionType, MessagePortMsg, MouseEventType, NavigationHistoryBehavior,
-    PortMessageTask, SWManagerMsg, SWManagerSenders, ScriptMsg as FromScriptMsg,
-    ScriptToConstellationChan, ServiceWorkerManagerFactory, ServiceWorkerMsg,
-    StructuredSerializedData, Theme, TraversalDirection, UpdatePipelineIdReason,
+    BroadcastMsg, ClipboardEventType, CompositorEvent, ConstellationControlMsg,
+    DiscardBrowsingContext, DocumentActivity, DocumentState, GamepadEvent, IFrameLoadInfo,
+    IFrameLoadInfoWithData, IFrameSandboxState, IFrameSizeMsg, Job, LayoutMsg as FromLayoutMsg,
+    LoadData, LoadOrigin, LogEntry, MediaSessionActionType, MessagePortMsg, MouseEventType,
+    NavigationHistoryBehavior, PortMessageTask, SWManagerMsg, SWManagerSenders,
+    ScriptMsg as FromScriptMsg, ScriptToConstellationChan, ServiceWorkerManagerFactory,
+    ServiceWorkerMsg, StructuredSerializedData, Theme, TraversalDirection, UpdatePipelineIdReason,
     WebDriverCommandMsg, WindowSizeData, WindowSizeType,
 };
 use serde::{Deserialize, Serialize};
@@ -1491,6 +1491,9 @@ where
             FromCompositorMsg::Gamepad(gamepad_event) => {
                 self.handle_gamepad_msg(gamepad_event);
             },
+            FromCompositorMsg::Clipboard(clipboard_event) => {
+                self.handle_clipboard_msg(clipboard_event);
+            },
         }
     }
 
@@ -4269,6 +4272,40 @@ where
 
     #[cfg_attr(
         feature = "tracing",
+        tracing::instrument(skip_all, fields(servo_profiling = true))
+    )]
+    fn handle_clipboard_msg(&mut self, event: ClipboardEventType) {
+        let focused_browsing_context_id = self
+            .webviews
+            .focused_webview()
+            .map(|(_, webview)| webview.focused_browsing_context_id);
+
+        if let Some(browsing_context_id) = focused_browsing_context_id {
+            let event = CompositorEvent::ClipboardEvent(event);
+            let pipeline_id = match self.browsing_contexts.get(&browsing_context_id) {
+                Some(ctx) => ctx.pipeline_id,
+                None => {
+                    return warn!(
+                        "{}: Got clipboard event for nonexistent browsing context",
+                        browsing_context_id,
+                    );
+                },
+            };
+            let msg = ConstellationControlMsg::SendEvent(pipeline_id, event);
+            let result = match self.pipelines.get(&pipeline_id) {
+                Some(pipeline) => pipeline.event_loop.send(msg),
+                None => {
+                    return debug!("{}: Got clipboard event after closure", pipeline_id);
+                },
+            };
+            if let Err(e) = result {
+                self.handle_send_error(pipeline_id, e);
+            }
+        }
+    }
+
+    #[cfg_attr(
+        feature = "tracing",
         tracing::instrument(skip_all, fields(servo_profiling = true), level = "trace")
     )]
     fn handle_reload_msg(&mut self, top_level_browsing_context_id: TopLevelBrowsingContextId) {
diff --git a/components/constellation/tracing.rs b/components/constellation/tracing.rs
index 88df4b49d6b..6c9924341da 100644
--- a/components/constellation/tracing.rs
+++ b/components/constellation/tracing.rs
@@ -93,6 +93,7 @@ mod from_compositor {
                 Self::IMEDismissed => target!("IMEDismissed"),
                 Self::ReadyToPresent(..) => target!("ReadyToPresent"),
                 Self::Gamepad(..) => target!("Gamepad"),
+                Self::Clipboard(..) => target!("Clipboard"),
             }
         }
     }
@@ -114,6 +115,7 @@ mod from_compositor {
                 Self::CompositionEvent(..) => target_variant!("CompositionEvent"),
                 Self::IMEDismissedEvent => target_variant!("IMEDismissedEvent"),
                 Self::GamepadEvent(..) => target_variant!("GamepadEvent"),
+                Self::ClipboardEvent(..) => target_variant!("ClipboardEvent"),
             }
         }
     }
@@ -215,6 +217,7 @@ mod from_script {
                 Self::WebViewBlurred => target_variant!("WebViewBlurred"),
                 Self::AllowUnload(..) => target_variant!("AllowUnload"),
                 Self::Keyboard(..) => target_variant!("Keyboard"),
+                Self::ClearClipboardContents => target_variant!("ClearClipboardContents"),
                 Self::GetClipboardContents(..) => target_variant!("GetClipboardContents"),
                 Self::SetClipboardContents(..) => target_variant!("SetClipboardContents"),
                 Self::SetCursor(..) => target_variant!("SetCursor"),
diff --git a/components/script/dom/clipboardevent.rs b/components/script/dom/clipboardevent.rs
new file mode 100644
index 00000000000..4791b73e7a9
--- /dev/null
+++ b/components/script/dom/clipboardevent.rs
@@ -0,0 +1,97 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+use dom_struct::dom_struct;
+use js::rust::HandleObject;
+
+use crate::dom::bindings::codegen::Bindings::ClipboardEventBinding::{
+    ClipboardEventInit, ClipboardEventMethods,
+};
+use crate::dom::bindings::codegen::Bindings::EventBinding::EventMethods;
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::reflector::reflect_dom_object_with_proto;
+use crate::dom::bindings::root::{DomRoot, MutNullableDom};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::datatransfer::DataTransfer;
+use crate::dom::event::{Event, EventBubbles, EventCancelable};
+use crate::dom::window::Window;
+use crate::script_runtime::CanGc;
+
+#[dom_struct]
+pub struct ClipboardEvent {
+    event: Event,
+    clipboard_data: MutNullableDom<DataTransfer>,
+}
+
+impl ClipboardEvent {
+    fn new_inherited() -> ClipboardEvent {
+        ClipboardEvent {
+            event: Event::new_inherited(),
+            clipboard_data: MutNullableDom::new(None),
+        }
+    }
+
+    pub(crate) fn new(
+        window: &Window,
+        proto: Option<HandleObject>,
+        type_: DOMString,
+        can_bubble: EventBubbles,
+        cancelable: EventCancelable,
+        clipboard_data: Option<&DataTransfer>,
+        can_gc: CanGc,
+    ) -> DomRoot<ClipboardEvent> {
+        let ev = reflect_dom_object_with_proto(
+            Box::new(ClipboardEvent::new_inherited()),
+            window,
+            proto,
+            can_gc,
+        );
+        ev.upcast::<Event>()
+            .InitEvent(type_, bool::from(can_bubble), bool::from(cancelable));
+        ev.clipboard_data.set(clipboard_data);
+        ev
+    }
+
+    pub(crate) fn set_clipboard_data(&self, clipboard_data: Option<&DataTransfer>) {
+        self.clipboard_data.set(clipboard_data);
+    }
+
+    pub(crate) fn get_clipboard_data(&self) -> Option<DomRoot<DataTransfer>> {
+        self.clipboard_data.get()
+    }
+}
+
+impl ClipboardEventMethods<crate::DomTypeHolder> for ClipboardEvent {
+    /// <https://www.w3.org/TR/clipboard-apis/#dom-clipboardevent-clipboardevent>
+    fn Constructor(
+        window: &Window,
+        proto: Option<HandleObject>,
+        can_gc: CanGc,
+        type_: DOMString,
+        init: &ClipboardEventInit,
+    ) -> DomRoot<ClipboardEvent> {
+        // Missing composed field
+        let bubbles = EventBubbles::from(init.parent.bubbles);
+        let cancelable = EventCancelable::from(init.parent.cancelable);
+        ClipboardEvent::new(
+            window,
+            proto,
+            type_,
+            bubbles,
+            cancelable,
+            init.clipboardData.as_deref(),
+            can_gc,
+        )
+    }
+
+    /// <https://www.w3.org/TR/clipboard-apis/#dom-clipboardevent-clipboarddata>
+    fn GetClipboardData(&self) -> Option<DomRoot<DataTransfer>> {
+        self.clipboard_data.get()
+    }
+
+    /// <https://dom.spec.whatwg.org/#dom-event-istrusted>
+    fn IsTrusted(&self) -> bool {
+        self.event.IsTrusted()
+    }
+}
diff --git a/components/script/dom/datatransfer.rs b/components/script/dom/datatransfer.rs
index 001d036919b..6f2e857c214 100644
--- a/components/script/dom/datatransfer.rs
+++ b/components/script/dom/datatransfer.rs
@@ -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/. */
 
-use std::cell::RefCell;
+use std::cell::{Ref, RefCell};
 use std::rc::Rc;
 
 use dom_struct::dom_struct;
@@ -64,11 +64,8 @@ impl DataTransfer {
         window: &Window,
         proto: Option<HandleObject>,
         can_gc: CanGc,
+        data_store: Rc<RefCell<Option<DragDataStore>>>,
     ) -> DomRoot<DataTransfer> {
-        let mut drag_data_store = DragDataStore::new();
-        drag_data_store.set_mode(Mode::ReadWrite);
-
-        let data_store = Rc::new(RefCell::new(Some(drag_data_store)));
         let item_list = DataTransferItemList::new(window, Rc::clone(&data_store));
 
         reflect_dom_object_with_proto(
@@ -78,6 +75,18 @@ impl DataTransfer {
             can_gc,
         )
     }
+
+    pub(crate) fn new(
+        window: &Window,
+        data_store: Rc<RefCell<Option<DragDataStore>>>,
+        can_gc: CanGc,
+    ) -> DomRoot<DataTransfer> {
+        Self::new_with_proto(window, None, can_gc, data_store)
+    }
+
+    pub(crate) fn data_store(&self) -> Option<Ref<DragDataStore>> {
+        Ref::filter_map(self.data_store.borrow(), |data_store| data_store.as_ref()).ok()
+    }
 }
 
 impl DataTransferMethods<crate::DomTypeHolder> for DataTransfer {
@@ -87,7 +96,12 @@ impl DataTransferMethods<crate::DomTypeHolder> for DataTransfer {
         proto: Option<HandleObject>,
         can_gc: CanGc,
     ) -> DomRoot<DataTransfer> {
-        DataTransfer::new_with_proto(window, proto, can_gc)
+        let mut drag_data_store = DragDataStore::new();
+        drag_data_store.set_mode(Mode::ReadWrite);
+
+        let data_store = Rc::new(RefCell::new(Some(drag_data_store)));
+
+        DataTransfer::new_with_proto(window, proto, can_gc, data_store)
     }
 
     /// <https://html.spec.whatwg.org/multipage/#dom-datatransfer-dropeffect>
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 11a0c0935cd..b73bec01967 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -48,8 +48,9 @@ use profile_traits::ipc as profile_ipc;
 use profile_traits::time::{TimerMetadata, TimerMetadataFrameType, TimerMetadataReflowType};
 use script_layout_interface::{PendingRestyle, TrustedNodeAddress};
 use script_traits::{
-    AnimationState, AnimationTickType, CompositorEvent, DocumentActivity, MouseButton,
-    MouseEventType, ScriptMsg, TouchEventType, TouchId, UntrustedNodeAddress, WheelDelta,
+    AnimationState, AnimationTickType, ClipboardEventType, CompositorEvent, DocumentActivity,
+    MouseButton, MouseEventType, ScriptMsg, TouchEventType, TouchId, UntrustedNodeAddress,
+    WheelDelta,
 };
 use servo_arc::Arc;
 use servo_atoms::Atom;
@@ -111,11 +112,13 @@ use crate::dom::bindings::xmlname::{
     namespace_from_domstring, validate_and_extract, xml_name_type,
 };
 use crate::dom::cdatasection::CDATASection;
+use crate::dom::clipboardevent::ClipboardEvent;
 use crate::dom::comment::Comment;
 use crate::dom::compositionevent::CompositionEvent;
 use crate::dom::cssstylesheet::CSSStyleSheet;
 use crate::dom::customelementregistry::CustomElementDefinition;
 use crate::dom::customevent::CustomEvent;
+use crate::dom::datatransfer::DataTransfer;
 use crate::dom::documentfragment::DocumentFragment;
 use crate::dom::documentorshadowroot::{DocumentOrShadowRoot, StyleSheetInDocument};
 use crate::dom::documenttype::DocumentType;
@@ -182,6 +185,7 @@ use crate::dom::wheelevent::WheelEvent;
 use crate::dom::window::Window;
 use crate::dom::windowproxy::WindowProxy;
 use crate::dom::xpathevaluator::XPathEvaluator;
+use crate::drag_data_store::{DragDataStore, Kind, Mode, PlainString};
 use crate::fetch::FetchCanceller;
 use crate::iframe_collection::IFrameCollection;
 use crate::messaging::{CommonScriptMsg, MainThreadScriptMsg};
@@ -1443,6 +1447,198 @@ impl Document {
         event.fire(target, can_gc);
     }
 
+    /// <https://www.w3.org/TR/clipboard-apis/#clipboard-actions>
+    pub(crate) fn handle_clipboard_action(
+        &self,
+        action: ClipboardEventType,
+        can_gc: CanGc,
+    ) -> bool {
+        // The script_triggered flag is set if the action runs because of a script, e.g. document.execCommand()
+        let script_triggered = false;
+
+        // The script_may_access_clipboard flag is set
+        // if action is paste and the script thread is allowed to read from clipboard or
+        // if action is copy or cut and the script thread is allowed to modify the clipboard
+        let script_may_access_clipboard = false;
+
+        // Step 1 If the script-triggered flag is set and the script-may-access-clipboard flag is unset
+        if script_triggered && !script_may_access_clipboard {
+            return false;
+        }
+
+        // Step 2 Fire a clipboard event
+        let event = ClipboardEvent::new(
+            &self.window,
+            None,
+            DOMString::from(action.as_str()),
+            EventBubbles::Bubbles,
+            EventCancelable::Cancelable,
+            None,
+            can_gc,
+        );
+        self.fire_clipboard_event(&event, action, can_gc);
+
+        // Step 3 If a script doesn't call preventDefault()
+        // the event will be handled inside target's VirtualMethods::handle_event
+
+        let e = event.upcast::<Event>();
+
+        if !e.IsTrusted() {
+            return false;
+        }
+
+        // Step 4 If the event was canceled, then
+        if e.DefaultPrevented() {
+            match e.Type().str() {
+                "copy" => {
+                    // Step 4.1 Call the write content to the clipboard algorithm,
+                    // passing on the DataTransferItemList items, a clear-was-called flag and a types-to-clear list.
+                    if let Some(clipboard_data) = event.get_clipboard_data() {
+                        let drag_data_store =
+                            clipboard_data.data_store().expect("This shouldn't fail");
+                        self.write_content_to_the_clipboard(&drag_data_store);
+                    }
+                },
+                "cut" => {
+                    // Step 4.1 Call the write content to the clipboard algorithm,
+                    // passing on the DataTransferItemList items, a clear-was-called flag and a types-to-clear list.
+                    if let Some(clipboard_data) = event.get_clipboard_data() {
+                        let drag_data_store =
+                            clipboard_data.data_store().expect("This shouldn't fail");
+                        self.write_content_to_the_clipboard(&drag_data_store);
+                    }
+
+                    // Step 4.2 Fire a clipboard event named clipboardchange
+                    self.fire_clipboardchange_event(can_gc);
+                },
+                "paste" => return false,
+                _ => (),
+            }
+        }
+        //Step 5
+        true
+    }
+
+    /// <https://www.w3.org/TR/clipboard-apis/#fire-a-clipboard-event>
+    fn fire_clipboard_event(
+        &self,
+        event: &ClipboardEvent,
+        action: ClipboardEventType,
+        can_gc: CanGc,
+    ) {
+        // Step 1 Let clear_was_called be false
+        // Step 2 Let types_to_clear an empty list
+        let mut drag_data_store = DragDataStore::new();
+
+        // Step 4 let clipboard-entry be the sequence number of clipboard content, null if the OS doesn't support it.
+
+        // Step 5 let trusted be true if the event is generated by the user agent, false otherwise
+        let trusted = true;
+
+        // Step 6 if the context is editable:
+        let focused = self.get_focused_element();
+        let body = self.GetBody();
+
+        let target = match (&focused, &body) {
+            (Some(focused), _) => focused.upcast(),
+            (&None, Some(body)) => body.upcast(),
+            (&None, &None) => self.window.upcast(),
+        };
+        // Step 6.2 else TODO require Selection see https://github.com/w3c/clipboard-apis/issues/70
+
+        // Step 7
+        match action {
+            ClipboardEventType::Copy | ClipboardEventType::Cut => {
+                // Step 7.2.1
+                drag_data_store.set_mode(Mode::ReadWrite);
+            },
+            ClipboardEventType::Paste(ref contents) => {
+                // Step 7.1.1
+                drag_data_store.set_mode(Mode::ReadOnly);
+                // Step 7.1.2 If trusted or the implementation gives script-generated events access to the clipboard
+                if trusted {
+                    // Step 7.1.2.1 For each clipboard-part on the OS clipboard:
+
+                    // Step 7.1.2.1.1 If clipboard-part contains plain text, then
+                    let plain_string = PlainString::new(
+                        DOMString::from_string(contents.to_string()),
+                        DOMString::from("text/plain"),
+                    );
+                    let _ = drag_data_store.add(Kind::Text(plain_string));
+
+                    // Step 7.1.2.1.2 TODO If clipboard-part represents file references, then for each file reference
+                    // Step 7.1.2.1.3 TODO If clipboard-part contains HTML- or XHTML-formatted text then
+
+                    // Step 7.1.3 Update clipboard-event-data’s files to match clipboard-event-data’s items
+                    // Step 7.1.4 Update clipboard-event-data’s types to match clipboard-event-data’s items
+                }
+            },
+            ClipboardEventType::Change => (),
+        }
+
+        // Step 3
+        let clipboard_event_data = DataTransfer::new(
+            &self.window,
+            Rc::new(RefCell::new(Some(drag_data_store))),
+            can_gc,
+        );
+
+        // Step 8
+        event.set_clipboard_data(Some(&clipboard_event_data));
+        let event = event.upcast::<Event>();
+        // Step 9
+        event.set_trusted(trusted);
+        // Step 10 Set event’s composed to true.
+        // Step 11
+        event.dispatch(target, false, can_gc);
+    }
+
+    pub(crate) fn fire_clipboardchange_event(&self, can_gc: CanGc) {
+        let clipboardchange_event = ClipboardEvent::new(
+            &self.window,
+            None,
+            DOMString::from("clipboardchange"),
+            EventBubbles::Bubbles,
+            EventCancelable::Cancelable,
+            None,
+            can_gc,
+        );
+        self.fire_clipboard_event(&clipboardchange_event, ClipboardEventType::Change, can_gc);
+    }
+
+    /// <https://www.w3.org/TR/clipboard-apis/#write-content-to-the-clipboard>
+    fn write_content_to_the_clipboard(&self, drag_data_store: &DragDataStore) {
+        // Step 1
+        if drag_data_store.list_len() > 0 {
+            // Step 1.1 Clear the clipboard.
+            self.send_to_embedder(EmbedderMsg::ClearClipboardContents);
+            // Step 1.2
+            for item in drag_data_store.iter_item_list() {
+                match item {
+                    Kind::Text(string) => {
+                        // Step 1.2.1.1 Ensure encoding is correct per OS and locale conventions
+                        // Step 1.2.1.2 Normalize line endings according to platform conventions
+                        // Step 1.2.1.3
+                        self.send_to_embedder(EmbedderMsg::SetClipboardContents(string.data()));
+                    },
+                    Kind::File(_) => {
+                        // Step 1.2.2 If data is of a type listed in the mandatory data types list, then
+                        // Step 1.2.2.1 Place part on clipboard with the appropriate OS clipboard format description
+                        // Step 1.2.3 Else this is left to the implementation
+                    },
+                }
+            }
+        } else {
+            // Step 2.1
+            if drag_data_store.clear_was_called {
+                // Step 2.1.1 If types-to-clear list is empty, clear the clipboard
+                self.send_to_embedder(EmbedderMsg::ClearClipboardContents);
+                // Step 2.1.2 Else remove the types in the list from the clipboard
+                // As of now this can't be done with Arboard, and it's possible that will be removed from the spec
+            }
+        }
+    }
+
     #[allow(unsafe_code)]
     pub(crate) unsafe fn handle_mouse_move_event(
         &self,
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index 7c4a1a626cd..9de33dcaa72 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -48,6 +48,7 @@ use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::DomObject;
 use crate::dom::bindings::root::{DomRoot, LayoutDom, MutNullableDom};
 use crate::dom::bindings::str::{DOMString, USVString};
+use crate::dom::clipboardevent::ClipboardEvent;
 use crate::dom::compositionevent::CompositionEvent;
 use crate::dom::document::Document;
 use crate::dom::element::{AttributeMutation, Element, LayoutElementHelpers};
@@ -79,7 +80,10 @@ use crate::textinput::KeyReaction::{
     DispatchInput, Nothing, RedrawSelection, TriggerDefaultAction,
 };
 use crate::textinput::Lines::Single;
-use crate::textinput::{Direction, SelectionDirection, TextInput, UTF16CodeUnits, UTF8Bytes};
+use crate::textinput::{
+    handle_text_clipboard_action, Direction, SelectionDirection, TextInput, UTF16CodeUnits,
+    UTF8Bytes,
+};
 
 const DEFAULT_SUBMIT_VALUE: &str = "Submit";
 const DEFAULT_RESET_VALUE: &str = "Reset";
@@ -2648,6 +2652,10 @@ impl VirtualMethods for HTMLInputElement {
                 }
                 event.mark_as_handled();
             }
+        } else if let Some(clipboard_event) = event.downcast::<ClipboardEvent>() {
+            if !event.DefaultPrevented() {
+                handle_text_clipboard_action(self, &self.textinput, clipboard_event, CanGc::note());
+            }
         }
 
         self.validity_state()
diff --git a/components/script/dom/htmltextareaelement.rs b/components/script/dom/htmltextareaelement.rs
index 9ea70e03bd6..fe0c822aa48 100644
--- a/components/script/dom/htmltextareaelement.rs
+++ b/components/script/dom/htmltextareaelement.rs
@@ -23,6 +23,7 @@ use crate::dom::bindings::error::ErrorResult;
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::root::{DomRoot, LayoutDom, MutNullableDom};
 use crate::dom::bindings::str::DOMString;
+use crate::dom::clipboardevent::ClipboardEvent;
 use crate::dom::compositionevent::CompositionEvent;
 use crate::dom::document::Document;
 use crate::dom::element::{AttributeMutation, Element, LayoutElementHelpers};
@@ -42,7 +43,8 @@ use crate::dom::validitystate::{ValidationFlags, ValidityState};
 use crate::dom::virtualmethods::VirtualMethods;
 use crate::script_runtime::CanGc;
 use crate::textinput::{
-    Direction, KeyReaction, Lines, SelectionDirection, TextInput, UTF16CodeUnits, UTF8Bytes,
+    handle_text_clipboard_action, Direction, KeyReaction, Lines, SelectionDirection, TextInput,
+    UTF16CodeUnits, UTF8Bytes,
 };
 
 #[dom_struct]
@@ -675,6 +677,10 @@ impl VirtualMethods for HTMLTextAreaElement {
                 }
                 event.mark_as_handled();
             }
+        } else if let Some(clipboard_event) = event.downcast::<ClipboardEvent>() {
+            if !event.DefaultPrevented() {
+                handle_text_clipboard_action(self, &self.textinput, clipboard_event, CanGc::note());
+            }
         }
 
         self.validity_state()
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index 8f51e796320..cfada01bf18 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -254,6 +254,7 @@ pub(crate) mod channelmergernode;
 pub(crate) mod channelsplitternode;
 pub(crate) mod characterdata;
 pub(crate) mod client;
+pub(crate) mod clipboardevent;
 pub(crate) mod closeevent;
 pub(crate) mod comment;
 pub(crate) mod compositionevent;
diff --git a/components/script/dom/webidls/ClipboardEvent.webidl b/components/script/dom/webidls/ClipboardEvent.webidl
new file mode 100644
index 00000000000..d23700d8415
--- /dev/null
+++ b/components/script/dom/webidls/ClipboardEvent.webidl
@@ -0,0 +1,15 @@
+/* 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://w3c.github.io/clipboard-apis/
+
+[Exposed=Window, Pref="dom_clipboardevent_enabled"]
+interface ClipboardEvent : Event {
+  constructor (DOMString type, optional ClipboardEventInit eventInitDict = {});
+  readonly attribute DataTransfer? clipboardData;
+};
+
+dictionary ClipboardEventInit : EventInit {
+  DataTransfer? clipboardData = null;
+};
diff --git a/components/script/drag_data_store.rs b/components/script/drag_data_store.rs
index a4db339dff4..6073695de90 100644
--- a/components/script/drag_data_store.rs
+++ b/components/script/drag_data_store.rs
@@ -31,6 +31,10 @@ impl PlainString {
     pub(crate) fn new(data: DOMString, type_: DOMString) -> Self {
         Self { data, type_ }
     }
+
+    pub fn data(&self) -> String {
+        self.data.to_string()
+    }
 }
 
 #[derive(Clone)]
@@ -99,7 +103,6 @@ pub(crate) enum Mode {
     /// <https://html.spec.whatwg.org/multipage/#concept-dnd-rw>
     ReadWrite,
     /// <https://html.spec.whatwg.org/multipage/#concept-dnd-ro>
-    #[allow(dead_code)] // TODO this used by ClipboardEvent.
     ReadOnly,
     /// <https://html.spec.whatwg.org/multipage/#concept-dnd-p>
     Protected,
@@ -115,6 +118,7 @@ pub(crate) struct DragDataStore {
     mode: Mode,
     /// <https://html.spec.whatwg.org/multipage/#drag-data-store-allowed-effects-state>
     allowed_effects_state: String,
+    pub clear_was_called: bool,
 }
 
 impl DragDataStore {
@@ -128,6 +132,7 @@ impl DragDataStore {
             bitmap: None,
             mode: Mode::Protected,
             allowed_effects_state: String::from("uninitialized"),
+            clear_was_called: false,
         }
     }
 
@@ -255,6 +260,10 @@ impl DragDataStore {
         self.item_list.len()
     }
 
+    pub(crate) fn iter_item_list(&self) -> std::slice::Iter<'_, Kind> {
+        self.item_list.iter()
+    }
+
     pub(crate) fn get_item(&self, index: usize) -> Option<Kind> {
         self.item_list.get(index).cloned()
     }
@@ -265,6 +274,7 @@ impl DragDataStore {
 
     pub(crate) fn clear_list(&mut self) {
         self.item_list.clear();
+        self.clear_was_called = true;
     }
 }
 
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 0cf14937c4c..08ce5fa7540 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -1141,6 +1141,10 @@ impl ScriptThread {
                 CompositorEvent::GamepadEvent(gamepad_event) => {
                     window.as_global_scope().handle_gamepad_event(gamepad_event);
                 },
+
+                CompositorEvent::ClipboardEvent(clipboard_action) => {
+                    document.handle_clipboard_action(clipboard_action, can_gc);
+                },
             }
         }
         ScriptThread::set_user_interacting(false);
diff --git a/components/script/textinput.rs b/components/script/textinput.rs
index 338303fc7b8..d59cd5b6a5d 100644
--- a/components/script/textinput.rs
+++ b/components/script/textinput.rs
@@ -10,12 +10,21 @@ use std::default::Default;
 use std::ops::{Add, AddAssign, Range};
 
 use keyboard_types::{Key, KeyState, Modifiers, ShortcutMatcher};
+use script_traits::ScriptToConstellationChan;
 use unicode_segmentation::UnicodeSegmentation;
 
 use crate::clipboard_provider::ClipboardProvider;
+use crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::codegen::Bindings::EventBinding::Event_Binding::EventMethods;
+use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::str::DOMString;
 use crate::dom::compositionevent::CompositionEvent;
+use crate::dom::event::Event;
 use crate::dom::keyboardevent::KeyboardEvent;
+use crate::dom::node::NodeTraits;
+use crate::dom::types::ClipboardEvent;
+use crate::drag_data_store::{DragDataStore, Kind};
+use crate::script_runtime::CanGc;
 
 #[derive(Clone, Copy, PartialEq)]
 pub enum Selection {
@@ -1128,4 +1137,88 @@ impl<T: ClipboardProvider> TextInput<T> {
             .fold(UTF8Bytes::zero(), |acc, x| acc + x.len_utf8());
         self.edit_point.index = byte_offset;
     }
+
+    fn paste_contents(&mut self, drag_data_store: &DragDataStore) {
+        for item in drag_data_store.iter_item_list() {
+            if let Kind::Text(string) = item {
+                self.insert_string(string.data());
+            }
+        }
+    }
+}
+
+/// <https://www.w3.org/TR/clipboard-apis/#clipboard-actions> step 3
+pub(crate) fn handle_text_clipboard_action(
+    owning_node: &impl NodeTraits,
+    textinput: &DomRefCell<TextInput<ScriptToConstellationChan>>,
+    event: &ClipboardEvent,
+    can_gc: CanGc,
+) -> bool {
+    let e = event.upcast::<Event>();
+
+    if !e.IsTrusted() {
+        return false;
+    }
+
+    // Step 3
+    match e.Type().str() {
+        "copy" => {
+            let selection = textinput.borrow().get_selection_text();
+
+            // Step 3.1 Copy the selected contents, if any, to the clipboard
+            if let Some(text) = selection {
+                textinput
+                    .borrow_mut()
+                    .clipboard_provider
+                    .set_clipboard_contents(text);
+            }
+
+            // Step 3.2 Fire a clipboard event named clipboardchange
+            owning_node
+                .owner_document()
+                .fire_clipboardchange_event(can_gc);
+        },
+        "cut" => {
+            let selection = textinput.borrow().get_selection_text();
+
+            // Step 3.1 If there is a selection in an editable context where cutting is enabled, then
+            if let Some(text) = selection {
+                // Step 3.1.1 Copy the selected contents, if any, to the clipboard
+                textinput
+                    .borrow_mut()
+                    .clipboard_provider
+                    .set_clipboard_contents(text);
+
+                // Step 3.1.2 Remove the contents of the selection from the document and collapse the selection.
+                textinput.borrow_mut().delete_char(Direction::Backward);
+
+                // Step 3.1.3 Fire a clipboard event named clipboardchange
+                owning_node
+                    .owner_document()
+                    .fire_clipboardchange_event(can_gc);
+
+                // Step 3.1.4 Queue tasks to fire any events that should fire due to the modification.
+            } else {
+                // Step 3.2 Else, if there is no selection or the context is not editable, then
+                return false;
+            }
+        },
+        "paste" => {
+            // Step 3.1 If there is a selection or cursor in an editable context where pasting is enabled, then
+            if let Some(data) = event.get_clipboard_data() {
+                // Step 3.1.1 Insert the most suitable content found on the clipboard, if any, into the context.
+                let drag_data_store = data.data_store().expect("This shouldn't fail");
+                textinput.borrow_mut().paste_contents(&drag_data_store);
+
+                // Step 3.1.2 Queue tasks to fire any events that should fire due to the modification.
+            } else {
+                // Step 3.2 Else return false.
+                return false;
+            }
+        },
+        _ => (),
+    }
+
+    //Step 5
+    true
 }
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index d9b2e560fba..a7215f372db 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -909,6 +909,9 @@ where
             EmbedderEvent::Vsync => {
                 self.compositor.on_vsync();
             },
+            EmbedderEvent::ClipboardAction(clipboard_event) => {
+                self.send_to_constellation(ConstellationMsg::Clipboard(clipboard_event));
+            },
         }
         false
     }
diff --git a/components/shared/compositing/constellation_msg.rs b/components/shared/compositing/constellation_msg.rs
index 46d7cc5978f..8b641ecf46e 100644
--- a/components/shared/compositing/constellation_msg.rs
+++ b/components/shared/compositing/constellation_msg.rs
@@ -12,8 +12,9 @@ use embedder_traits::Cursor;
 use ipc_channel::ipc::IpcSender;
 use keyboard_types::{CompositionEvent, KeyboardEvent};
 use script_traits::{
-    AnimationTickType, CompositorEvent, GamepadEvent, LogEntry, MediaSessionActionType, Theme,
-    TraversalDirection, WebDriverCommandMsg, WindowSizeData, WindowSizeType,
+    AnimationTickType, ClipboardEventType, CompositorEvent, GamepadEvent, LogEntry,
+    MediaSessionActionType, Theme, TraversalDirection, WebDriverCommandMsg, WindowSizeData,
+    WindowSizeType,
 };
 use servo_url::ServoUrl;
 
@@ -88,6 +89,8 @@ pub enum ConstellationMsg {
     ReadyToPresent(Vec<WebViewId>),
     /// Gamepad state has changed
     Gamepad(GamepadEvent),
+    /// Inform the constellation of a clipboard event.
+    Clipboard(ClipboardEventType),
 }
 
 impl fmt::Debug for ConstellationMsg {
@@ -134,6 +137,7 @@ impl ConstellationMsg {
             ClearCache => "ClearCache",
             ReadyToPresent(..) => "ReadyToPresent",
             Gamepad(..) => "Gamepad",
+            Clipboard(..) => "Clipboard",
         }
     }
 }
diff --git a/components/shared/embedder/lib.rs b/components/shared/embedder/lib.rs
index 2548cad70f3..b03fa1035df 100644
--- a/components/shared/embedder/lib.rs
+++ b/components/shared/embedder/lib.rs
@@ -192,6 +192,8 @@ pub enum EmbedderMsg {
     AllowUnload(IpcSender<bool>),
     /// Sends an unconsumed key event back to the embedder.
     Keyboard(KeyboardEvent),
+    /// Inform embedder to clear the clipboard
+    ClearClipboardContents,
     /// Gets system clipboard contents
     GetClipboardContents(IpcSender<String>),
     /// Sets system clipboard contents
@@ -256,6 +258,7 @@ pub enum CompositorEventVariant {
     CompositionEvent,
     IMEDismissedEvent,
     GamepadEvent,
+    ClipboardEvent,
 }
 
 impl Debug for EmbedderMsg {
@@ -269,6 +272,7 @@ impl Debug for EmbedderMsg {
             EmbedderMsg::AllowUnload(..) => write!(f, "AllowUnload"),
             EmbedderMsg::AllowNavigationRequest(..) => write!(f, "AllowNavigationRequest"),
             EmbedderMsg::Keyboard(..) => write!(f, "Keyboard"),
+            EmbedderMsg::ClearClipboardContents => write!(f, "ClearClipboardContents"),
             EmbedderMsg::GetClipboardContents(..) => write!(f, "GetClipboardContents"),
             EmbedderMsg::SetClipboardContents(..) => write!(f, "SetClipboardContents"),
             EmbedderMsg::SetCursor(..) => write!(f, "SetCursor"),
diff --git a/components/shared/script/lib.rs b/components/shared/script/lib.rs
index e6901be54b6..60f7abba6d6 100644
--- a/components/shared/script/lib.rs
+++ b/components/shared/script/lib.rs
@@ -535,6 +535,31 @@ pub struct WheelDelta {
     pub mode: WheelMode,
 }
 
+/// The types of clipboard events
+#[derive(Clone, Debug, Deserialize, Serialize)]
+pub enum ClipboardEventType {
+    /// Contents of the system clipboard are changed
+    Change,
+    /// Copy
+    Copy,
+    /// Cut
+    Cut,
+    /// Paste
+    Paste(String),
+}
+
+impl ClipboardEventType {
+    /// Convert to event name
+    pub fn as_str(&self) -> &str {
+        match *self {
+            ClipboardEventType::Change => "clipboardchange",
+            ClipboardEventType::Copy => "copy",
+            ClipboardEventType::Cut => "cut",
+            ClipboardEventType::Paste(..) => "paste",
+        }
+    }
+}
+
 /// Events from the compositor that the script thread needs to know about
 #[derive(Debug, Deserialize, Serialize)]
 pub enum CompositorEvent {
@@ -574,6 +599,8 @@ pub enum CompositorEvent {
     IMEDismissedEvent,
     /// Connected gamepad state updated
     GamepadEvent(GamepadEvent),
+    /// A clipboard action was requested
+    ClipboardEvent(ClipboardEventType),
 }
 
 impl From<&CompositorEvent> for CompositorEventVariant {
@@ -588,6 +615,7 @@ impl From<&CompositorEvent> for CompositorEventVariant {
             CompositorEvent::CompositionEvent(..) => CompositorEventVariant::CompositionEvent,
             CompositorEvent::IMEDismissedEvent => CompositorEventVariant::IMEDismissedEvent,
             CompositorEvent::GamepadEvent(..) => CompositorEventVariant::GamepadEvent,
+            CompositorEvent::ClipboardEvent(..) => CompositorEventVariant::ClipboardEvent,
         }
     }
 }