Bug 1629113 - Add nsIPromptCollection. r=johannh,pbz

This new prompt service will handle specialized prompts like beforeUnloadCheck.

The plan is to eventually phase out generic prompts like confirmExBC and just
have specialized prompts.

Differential Revision: https://phabricator.services.mozilla.com/D72720

browser/components/moz.build

@@ -46,6 +46,7 @@ DIRS += [
     'pocket',
     'preferences',
     'privatebrowsing',
+    'prompts',
     'protections',
     'protocolhandler',
     'resistfingerprinting',

browser/components/prompts/PromptCollection.jsm

@@ -0,0 +1,85 @@
+/* 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/. */
+
+"use strict";
+
+var EXPORTED_SYMBOLS = ["PromptCollection"];
+
+const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+const { XPCOMUtils } = ChromeUtils.import(
+  "resource://gre/modules/XPCOMUtils.jsm"
+);
+
+/**
+ * Implements nsIPromptCollection
+ * @class PromptCollection
+ */
+class PromptCollection {
+  beforeUnloadCheck(browsingContext) {
+    let title;
+    let message;
+    let leaveLabel;
+    let stayLabel;
+
+    try {
+      title = this.domBundle.GetStringFromName("OnBeforeUnloadTitle");
+      message = this.domBundle.GetStringFromName("OnBeforeUnloadMessage");
+      leaveLabel = this.domBundle.GetStringFromName(
+        "OnBeforeUnloadLeaveButton"
+      );
+      stayLabel = this.domBundle.GetStringFromName("OnBeforeUnloadStayButton");
+    } catch (exception) {
+      Cu.reportError("Failed to get strings from dom.properties");
+      return false;
+    }
+
+    let contentViewer = browsingContext?.docShell?.contentViewer;
+    let modalType = contentViewer?.isTabModalPromptAllowed
+      ? Ci.nsIPromptService.MODAL_TYPE_CONTENT
+      : Ci.nsIPromptService.MODAL_TYPE_WINDOW;
+
+    let buttonFlags =
+      Ci.nsIPromptService.BUTTON_POS_0_DEFAULT |
+      (Ci.nsIPromptService.BUTTON_TITLE_IS_STRING *
+        Ci.nsIPromptService.BUTTON_POS_0) |
+      (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,
+      {}
+    );
+
+    return buttonPressed === 0;
+  }
+}
+
+XPCOMUtils.defineLazyGetter(
+  PromptCollection.prototype,
+  "domBundle",
+  function() {
+    let bundle = Services.strings.createBundle(
+      "chrome://global/locale/dom/dom.properties"
+    );
+    if (!bundle) {
+      throw new Error("String bundle for dom not present!");
+    }
+    return bundle;
+  }
+);
+
+PromptCollection.prototype.classID = Components.ID(
+  "{7913837c-9623-11ea-bb37-0242ac130002}"
+);
+PromptCollection.prototype.QueryInterface = ChromeUtils.generateQI([
+  Ci.nsIPromptCollection,
+]);

browser/components/prompts/components.conf

@@ -0,0 +1,12 @@
+# 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/.
+
+Classes = [
+    {
+        'cid': '{7913837c-9623-11ea-bb37-0242ac130002}',
+        'contract_ids': ['@mozilla.org/embedcomp/prompt-collection;1'],
+        'jsm': 'resource:///modules/PromptCollection.jsm',
+        'constructor': 'PromptCollection',
+    },
+]

browser/components/prompts/moz.build

@@ -0,0 +1,14 @@
+# 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/.
+
+with Files("**"):
+    BUG_COMPONENT = ("Toolkit", "Notifications and Alerts")
+
+EXTRA_JS_MODULES += [
+  'PromptCollection.jsm',
+]
+
+XPCOM_MANIFESTS += [
+  'components.conf',
+]

toolkit/components/windowwatcher/moz.build

@@ -12,6 +12,7 @@ TEST_DIRS += ['test']
 XPIDL_SOURCES += [
     'nsIDialogParamBlock.idl',
     'nsIOpenWindowInfo.idl',
+    'nsIPromptCollection.idl',
     'nsIPromptFactory.idl',
     'nsIPromptService.idl',
     'nsIWindowWatcher.idl',

toolkit/components/windowwatcher/nsIPromptCollection.idl

@@ -0,0 +1,25 @@
+/* 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/. */
+
+#include "nsISupports.idl"
+
+webidl BrowsingContext;
+
+/**
+ * This interface contains various specialized prompts that the app can
+ * implement.
+ */
+[scriptable, uuid(7913837c-9623-11ea-bb37-0242ac130002)]
+interface nsIPromptCollection : nsISupports
+{
+  /**
+   * Puts up a dialog for the before unload prompt.
+   *
+   * @param aBrowsingContext
+   *        The browsing context the prompt should be opened for.
+   *
+   * @return true if the page should be allowed to navigate away
+   */
+  boolean beforeUnloadCheck(in BrowsingContext aBrowsingContext);
+};