libservo: Clean up interfaces for alert()/confirm()/prompt() (#35579)

Signed-off-by: Delan Azabani <dazabani@igalia.com>

components/constellation/tracing.rs

@@ -201,7 +201,7 @@ mod from_script {
                 Self::ChangePageTitle(..) => target_variant!("ChangePageTitle"),
                 Self::MoveTo(..) => target_variant!("MoveTo"),
                 Self::ResizeTo(..) => target_variant!("ResizeTo"),
-                Self::Prompt(..) => target_variant!("Prompt"),
+                Self::ShowSimpleDialog(..) => target_variant!("ShowSimpleDialog"),
                 Self::RequestAuthentication(..) => target_variant!("RequestAuthentication"),
                 Self::ShowContextMenu(..) => target_variant!("ShowContextMenu"),
                 Self::AllowNavigationRequest(..) => target_variant!("AllowNavigationRequest"),

components/script/dom/window.rs

@@ -26,8 +26,8 @@ use cssparser::{Parser, ParserInput, SourceLocation};
 use devtools_traits::{ScriptToDevtoolsControlMsg, TimelineMarker, TimelineMarkerType};
 use dom_struct::dom_struct;
 use embedder_traits::{
-    EmbedderMsg, PromptDefinition, PromptOrigin, PromptResult, Theme, WebDriverJSError,
-    WebDriverJSResult,
+    AlertResponse, ConfirmResponse, EmbedderMsg, PromptResponse, SimpleDialog, Theme,
+    WebDriverJSError, WebDriverJSResult,
 };
 use euclid::default::{Point2D as UntypedPoint2D, Rect as UntypedRect};
 use euclid::{Point2D, Rect, Scale, Size2D, Vector2D};
@@ -736,30 +736,43 @@ impl WindowMethods<crate::DomTypeHolder> for Window {
         }
         let (sender, receiver) =
             ProfiledIpc::channel(self.global().time_profiler_chan().clone()).unwrap();
-        let prompt = PromptDefinition::Alert(s.to_string(), sender);
-        let msg = EmbedderMsg::Prompt(self.webview_id(), prompt, PromptOrigin::Untrusted);
+        let dialog = SimpleDialog::Alert {
+            message: s.to_string(),
+            response_sender: sender,
+        };
+        let msg = EmbedderMsg::ShowSimpleDialog(self.webview_id(), dialog);
         self.send_to_embedder(msg);
-        receiver.recv().unwrap();
+        let AlertResponse::Ok = receiver.recv().unwrap();
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-confirm
     fn Confirm(&self, s: DOMString) -> bool {
         let (sender, receiver) =
             ProfiledIpc::channel(self.global().time_profiler_chan().clone()).unwrap();
-        let prompt = PromptDefinition::OkCancel(s.to_string(), sender);
-        let msg = EmbedderMsg::Prompt(self.webview_id(), prompt, PromptOrigin::Untrusted);
+        let dialog = SimpleDialog::Confirm {
+            message: s.to_string(),
+            response_sender: sender,
+        };
+        let msg = EmbedderMsg::ShowSimpleDialog(self.webview_id(), dialog);
         self.send_to_embedder(msg);
-        receiver.recv().unwrap() == PromptResult::Primary
+        receiver.recv().unwrap() == ConfirmResponse::Ok
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-prompt
     fn Prompt(&self, message: DOMString, default: DOMString) -> Option<DOMString> {
         let (sender, receiver) =
             ProfiledIpc::channel(self.global().time_profiler_chan().clone()).unwrap();
-        let prompt = PromptDefinition::Input(message.to_string(), default.to_string(), sender);
-        let msg = EmbedderMsg::Prompt(self.webview_id(), prompt, PromptOrigin::Untrusted);
+        let dialog = SimpleDialog::Prompt {
+            message: message.to_string(),
+            default: default.to_string(),
+            response_sender: sender,
+        };
+        let msg = EmbedderMsg::ShowSimpleDialog(self.webview_id(), dialog);
         self.send_to_embedder(msg);
-        receiver.recv().unwrap().map(|s| s.into())
+        match receiver.recv().unwrap() {
+            PromptResponse::Ok(input) => Some(input.into()),
+            PromptResponse::Cancel => None,
+        }
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-window-stop

components/servo/lib.rs

@@ -708,11 +708,11 @@ impl Servo {
                     webview.delegate().request_resize_to(webview, size);
                 }
             },
-            EmbedderMsg::Prompt(webview_id, prompt_definition, prompt_origin) => {
+            EmbedderMsg::ShowSimpleDialog(webview_id, prompt_definition) => {
                 if let Some(webview) = self.get_webview_handle(webview_id) {
                     webview
                         .delegate()
-                        .show_prompt(webview, prompt_definition, prompt_origin);
+                        .show_simple_dialog(webview, prompt_definition);
                 }
             },
             EmbedderMsg::ShowContextMenu(webview_id, ipc_sender, title, items) => {

components/servo/webview_delegate.rs

@@ -9,8 +9,7 @@ use compositing_traits::ConstellationMsg;
 use embedder_traits::{
     AllowOrDeny, AuthenticationResponse, ContextMenuResult, Cursor, FilterPattern,
     GamepadHapticEffectType, InputMethodType, LoadStatus, MediaSessionEvent, PermissionFeature,
-    PromptDefinition, PromptOrigin, WebResourceRequest, WebResourceResponse,
-    WebResourceResponseMsg,
+    SimpleDialog, WebResourceRequest, WebResourceResponse, WebResourceResponseMsg,
 };
 use ipc_channel::ipc::IpcSender;
 use keyboard_types::KeyboardEvent;
@@ -338,17 +337,25 @@ pub trait WebViewDelegate {
     ) {
     }
 
-    /// Show dialog to user
+    /// Show the user a [simple dialog](https://html.spec.whatwg.org/multipage/#simple-dialogs) (`alert()`, `confirm()`,
+    /// or `prompt()`). Since their messages are controlled by web content, they should be presented to the user in a
+    /// way that makes them impossible to mistake for browser UI.
     /// TODO: This API needs to be reworked to match the new model of how responses are sent.
-    fn show_prompt(&self, _webview: WebView, prompt: PromptDefinition, _: PromptOrigin) {
-        let _ = match prompt {
-            PromptDefinition::Alert(_, response_sender) => response_sender.send(()),
-            PromptDefinition::OkCancel(_, response_sender) => {
-                response_sender.send(embedder_traits::PromptResult::Dismissed)
-            },
-            PromptDefinition::Input(_, _, response_sender) => response_sender.send(None),
+    fn show_simple_dialog(&self, _webview: WebView, dialog: SimpleDialog) {
+        // Return the DOM-specified default value for when we **cannot show simple dialogs**.
+        let _ = match dialog {
+            SimpleDialog::Alert {
+                response_sender, ..
+            } => response_sender.send(Default::default()),
+            SimpleDialog::Confirm {
+                response_sender, ..
+            } => response_sender.send(Default::default()),
+            SimpleDialog::Prompt {
+                response_sender, ..
+            } => response_sender.send(Default::default()),
         };
     }
+
     /// Show a context menu to the user
     fn show_context_menu(
         &self,

components/shared/embedder/lib.rs

@@ -123,14 +123,30 @@ pub enum ContextMenuResult {
     Selected(usize),
 }
 
+/// [Simple dialogs](https://html.spec.whatwg.org/multipage/#simple-dialogs) are synchronous dialogs
+/// that can be opened by web content. Since their messages are controlled by web content, they
+/// should be presented to the user in a way that makes them impossible to mistake for browser UI.
 #[derive(Deserialize, Serialize)]
-pub enum PromptDefinition {
-    /// Show a message.
-    Alert(String, IpcSender<()>),
-    /// Ask a Ok/Cancel question.
-    OkCancel(String, IpcSender<PromptResult>),
-    /// Ask the user to enter text.
-    Input(String, String, IpcSender<Option<String>>),
+pub enum SimpleDialog {
+    /// [`alert()`](https://html.spec.whatwg.org/multipage/#dom-alert).
+    /// TODO: Include details about the document origin.
+    Alert {
+        message: String,
+        response_sender: IpcSender<AlertResponse>,
+    },
+    /// [`confirm()`](https://html.spec.whatwg.org/multipage/#dom-confirm).
+    /// TODO: Include details about the document origin.
+    Confirm {
+        message: String,
+        response_sender: IpcSender<ConfirmResponse>,
+    },
+    /// [`prompt()`](https://html.spec.whatwg.org/multipage/#dom-prompt).
+    /// TODO: Include details about the document origin.
+    Prompt {
+        message: String,
+        default: String,
+        response_sender: IpcSender<PromptResponse>,
+    },
 }
 
 #[derive(Debug, Default, Deserialize, Serialize)]
@@ -142,22 +158,52 @@ pub struct AuthenticationResponse {
 }
 
 #[derive(Deserialize, PartialEq, Serialize)]
-pub enum PromptOrigin {
-    /// Prompt is triggered from content (window.prompt/alert/confirm/…).
-    /// Prompt message is unknown.
-    Untrusted,
-    /// Prompt is triggered from Servo (ask for permission, show error,…).
-    Trusted,
+pub enum AlertResponse {
+    /// The user chose Ok, or the dialog was otherwise dismissed or ignored.
+    Ok,
+}
+
+impl Default for AlertResponse {
+    fn default() -> Self {
+        // Per <https://html.spec.whatwg.org/multipage/#dom-alert>,
+        // if we **cannot show simple dialogs**, including cases where the user or user agent decides to ignore
+        // all modal dialogs, we need to return (which represents Ok).
+        Self::Ok
+    }
 }
 
 #[derive(Deserialize, PartialEq, Serialize)]
-pub enum PromptResult {
-    /// Prompt was closed by clicking on the primary button (ok/yes)
-    Primary,
-    /// Prompt was closed by clicking on the secondary button (cancel/no)
-    Secondary,
-    /// Prompt was dismissed
-    Dismissed,
+pub enum ConfirmResponse {
+    /// The user chose Ok.
+    Ok,
+    /// The user chose Cancel, or the dialog was otherwise dismissed or ignored.
+    Cancel,
+}
+
+impl Default for ConfirmResponse {
+    fn default() -> Self {
+        // Per <https://html.spec.whatwg.org/multipage/#dom-confirm>,
+        // if we **cannot show simple dialogs**, including cases where the user or user agent decides to ignore
+        // all modal dialogs, we need to return false (which represents Cancel), not true (Ok).
+        Self::Cancel
+    }
+}
+
+#[derive(Deserialize, PartialEq, Serialize)]
+pub enum PromptResponse {
+    /// The user chose Ok, with the given input.
+    Ok(String),
+    /// The user chose Cancel, or the dialog was otherwise dismissed or ignored.
+    Cancel,
+}
+
+impl Default for PromptResponse {
+    fn default() -> Self {
+        // Per <https://html.spec.whatwg.org/multipage/#dom-prompt>,
+        // if we **cannot show simple dialogs**, including cases where the user or user agent decides to ignore
+        // all modal dialogs, we need to return null (which represents Cancel), not the default input.
+        Self::Cancel
+    }
 }
 
 /// A response to a request to allow or deny an action.
@@ -177,8 +223,10 @@ pub enum EmbedderMsg {
     MoveTo(WebViewId, DeviceIntPoint),
     /// Resize the window to size
     ResizeTo(WebViewId, DeviceIntSize),
-    /// Show dialog to user
-    Prompt(WebViewId, PromptDefinition, PromptOrigin),
+    /// Show the user a [simple dialog](https://html.spec.whatwg.org/multipage/#simple-dialogs) (`alert()`, `confirm()`,
+    /// or `prompt()`). Since their messages are controlled by web content, they should be presented to the user in a
+    /// way that makes them impossible to mistake for browser UI.
+    ShowSimpleDialog(WebViewId, SimpleDialog),
     /// Request authentication for a load or navigation from the embedder.
     RequestAuthentication(
         WebViewId,
@@ -280,7 +328,7 @@ impl Debug for EmbedderMsg {
             EmbedderMsg::ChangePageTitle(..) => write!(f, "ChangePageTitle"),
             EmbedderMsg::MoveTo(..) => write!(f, "MoveTo"),
             EmbedderMsg::ResizeTo(..) => write!(f, "ResizeTo"),
-            EmbedderMsg::Prompt(..) => write!(f, "Prompt"),
+            EmbedderMsg::ShowSimpleDialog(..) => write!(f, "ShowSimpleDialog"),
             EmbedderMsg::RequestAuthentication(..) => write!(f, "RequestAuthentication"),
             EmbedderMsg::AllowUnload(..) => write!(f, "AllowUnload"),
             EmbedderMsg::AllowNavigationRequest(..) => write!(f, "AllowNavigationRequest"),