Bug 1655866: Part 1 - Add async version of beforeUnloadCheck prompt. r=geckoview-reviewers,Gijs,agi

Differential Revision: https://phabricator.services.mozilla.com/D88314

browser/components/prompts/PromptCollection.jsm

@@ -71,7 +71,7 @@ class PromptCollection {
     return buttonPressed === 0;
   }
 
-  beforeUnloadCheck(browsingContext) {
+  beforeUnloadCheckInternal(browsingContext, sync) {
     let title;
     let message;
     let leaveLabel;
@@ -94,9 +94,17 @@ class PromptCollection {
     }
 
     let contentViewer = browsingContext?.docShell?.contentViewer;
-    let modalType = contentViewer?.isTabModalPromptAllowed
-      ? Ci.nsIPromptService.MODAL_TYPE_CONTENT
-      : Ci.nsIPromptService.MODAL_TYPE_WINDOW;
+
+    // TODO: Do we really want to allow modal dialogs from inactive
+    // content viewers at all, particularly for permit unload prompts?
+    let modalAllowed = contentViewer
+      ? contentViewer.isTabModalPromptAllowed
+      : browsingContext.ancestorsAreCurrent;
+
+    let modalType =
+      Ci.nsIPromptService[
+        modalAllowed ? "MODAL_TYPE_CONTENT" : "MODAL_TYPE_WINDOW"
+      ];
 
     let buttonFlags =
       Ci.nsIPromptService.BUTTON_POS_0_DEFAULT |
@@ -105,20 +113,55 @@ class PromptCollection {
       (Ci.nsIPromptService.BUTTON_TITLE_IS_STRING *
         Ci.nsIPromptService.BUTTON_POS_1);
 
-    let buttonPressed = Services.prompt.confirmExBC(
-      browsingContext,
-      modalType,
-      title,
-      message,
-      buttonFlags,
-      leaveLabel,
-      stayLabel,
-      null,
-      null,
-      {}
-    );
+    if (sync) {
+      let buttonNumClicked = Services.prompt.confirmExBC(
+        browsingContext,
+        modalType,
+        title,
+        message,
+        buttonFlags,
+        leaveLabel,
+        stayLabel,
+        null,
+        null,
+        {}
+      );
 
-    return buttonPressed === 0;
+      return buttonNumClicked === 0;
+    }
+
+    return Services.prompt
+      .asyncConfirmEx(
+        browsingContext,
+        modalType,
+        title,
+        message,
+        buttonFlags,
+        leaveLabel,
+        stayLabel,
+        null,
+        null,
+        false,
+        // Tell the prompt service that this is a permit unload prompt
+        // so that it can set the appropriate flag on the detail object
+        // of the events it dispatches. This happens automatically for
+        // the sync version of the prompt, which is always dispatched
+        // from the content process, where the flag comes from the
+        // content viewer which triggers the prompt.
+        { inPermitUnload: true }
+      )
+      .then(
+        result =>
+          result.QueryInterface(Ci.nsIPropertyBag2).get("buttonNumClicked") == 0
+      );
+  }
+
+  beforeUnloadCheck(browsingContext) {
+    return this.beforeUnloadCheckInternal(browsingContext, /* sync */ true);
+  }
+
+  asyncBeforeUnloadCheck(browsingContext) {
+    return this.beforeUnloadCheckInternal(browsingContext, /* sync */ false);
   }
 }
 
@@ -144,9 +187,6 @@ for (const [bundleName, bundleUrl] of Object.entries(BUNDLES)) {
   );
 }
 
-PromptCollection.prototype.classID = Components.ID(
-  "{7913837c-9623-11ea-bb37-0242ac130002}"
-);
 PromptCollection.prototype.QueryInterface = ChromeUtils.generateQI([
   "nsIPromptCollection",
 ]);

dom/chrome-webidl/BrowsingContext.webidl

@@ -68,6 +68,8 @@ interface BrowsingContext {
 
   readonly attribute WindowContext? topWindowContext;
 
+  readonly attribute boolean ancestorsAreCurrent;
+
   [SetterThrows] attribute [TreatNullAs=EmptyString] DOMString customPlatform;
 
   [SetterThrows] attribute [TreatNullAs=EmptyString] DOMString customUserAgent;

mobile/android/components/geckoview/PromptCollection.jsm

@@ -37,11 +37,17 @@ class PromptCollection {
     const result = prompter.showPrompt(msg);
     return !!result?.allow;
   }
-}
 
-PromptCollection.prototype.classID = Components.ID(
-  "{3e30d2a0-9934-11ea-bb37-0242ac130002}"
-);
+  asyncBeforeUnloadCheck(browsingContext) {
+    return new Promise(resolve => {
+      const msg = {
+        type: "beforeUnload",
+      };
+      const prompter = new GeckoViewPrompter(browsingContext);
+      prompter.asyncShowPrompt(msg, resolve);
+    }).then(result => !!result?.allow);
+  }
+}
 
 PromptCollection.prototype.QueryInterface = ChromeUtils.generateQI([
   "nsIPromptCollection",

toolkit/components/prompts/src/Prompter.jsm

@@ -346,6 +346,7 @@ Prompter.prototype = {
    * @param {String} checkLabel - Text to appear with the checkbox.
    *        Null if no checkbox.
    * @param {Boolean} checkValue - The initial checked state of the checkbox.
+   * @param {Object} [extraArgs] - Extra arguments for the prompt metadata.
    * @returns {Promise<nsIPropertyBag<{ buttonNumClicked: Number, checked: Boolean }>>}
    */
   asyncConfirmEx(browsingContext, modalType, ...promptArgs) {
@@ -1400,7 +1401,8 @@ class ModalPrompter {
     button1,
     button2,
     checkLabel,
-    checkValue
+    checkValue,
+    extraArgs = {}
   ) {
     if (!title) {
       title = PromptUtils.getLocalizedString("Confirm");
@@ -1414,6 +1416,7 @@ class ModalPrompter {
       checked: this.async ? checkValue : checkValue.value,
       ok: false,
       buttonNumClicked: 1,
+      ...extraArgs,
     };
 
     let [

toolkit/components/windowwatcher/nsIPromptCollection.idl

@@ -23,6 +23,13 @@ interface nsIPromptCollection : nsISupports
    */
   boolean beforeUnloadCheck(in BrowsingContext aBrowsingContext);
 
+  /**
+   * Like `beforeUnloadCheck`, but does not spin a nested event loop, and
+   * instead returns a promise which resolves to true if navigation should be
+   * allowed, and false if not.
+   */
+  Promise asyncBeforeUnloadCheck(in BrowsingContext aBrowsingContext);
+
   /**
    * Puts up a dialog for the confirm repost prompt.
    *

toolkit/components/windowwatcher/nsIPromptService.idl

@@ -364,7 +364,8 @@ interface nsIPromptService : nsISupports
                       in wstring aButton1Title,
                       in wstring aButton2Title,
                       in wstring aCheckMsg,
-                      in boolean aCheckState);
+                      in boolean aCheckState,
+                      [optional] in jsval aExtraArgs);
   /**
    * Puts up a dialog with an edit field and an optional, labeled checkbox.
    *