Bug 1851761 - [bidi] Add `defaultValue` field to the "browsingContext.userPromptOpened" event. r=webdriver-reviewers,whimboo

Differential Revision: https://phabricator.services.mozilla.com/D189633

remote/shared/Prompt.sys.mjs

@@ -210,4 +210,18 @@ modal.Dialog = class {
     }
     return this.ui.infoBody.textContent;
   }
+
+  /**
+   * Returns text of the prompt input.
+   *
+   * @returns {string}
+   *     Returns string on desktop and Promise on Android.
+   */
+  async getInputText() {
+    if (lazy.AppInfo.isAndroid) {
+      const textPromise = await this.window.getInputText();
+      return textPromise;
+    }
+    return this.ui.loginTextbox.value;
+  }
 };

remote/test/puppeteer/test/TestExpectations.json

@@ -1679,12 +1679,6 @@
     "parameters": ["cdp", "firefox"],
     "expectations": ["FAIL"]
   },
-  {
-    "testIdPattern": "[dialog.spec] Page.Events.Dialog should allow accepting prompts",
-    "platforms": ["darwin", "linux", "win32"],
-    "parameters": ["firefox", "webDriverBiDi"],
-    "expectations": ["FAIL"]
-  },
   {
     "testIdPattern": "[dialog.spec] Page.Events.Dialog should allow accepting prompts",
     "platforms": ["darwin", "linux", "win32"],

remote/webdriver-bidi/modules/root/browsingContext.sys.mjs

@@ -1314,13 +1314,25 @@ class BrowsingContextModule extends Module {
         type: lazy.WindowGlobalMessageHandler.type,
       };
 
-      this.emitEvent(
+      const eventPayload = {
-        "browsingContext.userPromptOpened",
-        {
         context: contextId,
         type: prompt.promptType,
         message: await prompt.getText(),
-        },
+      };
+
+      // Bug 1859814: Since the platform doesn't provide the access to the `defaultValue` of the prompt,
+      // we use prompt the `value` instead. The `value` is set to `defaultValue` when `defaultValue` is provided.
+      // This approach doesn't allow us to distinguish between the `defaultValue` being set to an empty string and
+      // `defaultValue` not set, because `value` is always defaulted to an empty string.
+      // We should switch to using the actual `defaultValue` when it's available and check for the `null` here.
+      const defaultValue = await prompt.getInputText();
+      if (defaultValue) {
+        eventPayload.defaultValue = defaultValue;
+      }
+
+      this.emitEvent(
+        "browsingContext.userPromptOpened",
+        eventPayload,
         contextInfo
       );
     }

testing/web-platform/meta/webdriver/tests/bidi/browsing_context/user_prompt_opened/user_prompt_opened.py.ini

@@ -2,6 +2,3 @@
   [test_subscribe_to_one_context[window\]]
     disabled:
       if os == "android": Not supported
-
-  [test_prompt_default_value]
-    expected: FAIL