Autotest API for testing AssistantState::NEW_READY

This CL introduces the Autotest APIs used to test that the |NEW_READY| signal is
sent out when the Assistant is ready to handle queries.

Change-Id: I1dd1c366dece11be8b4c6c84e6a5c808bb110453
BUG: b/143381021
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1881968
Commit-Queue: Jeroen Dhollander <jeroendh@google.com>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Xiaohui Chen <xiaohuic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713546}

chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.cc

@@ -1979,6 +1979,59 @@ void AutotestPrivateSetAssistantEnabledFunction::Timeout() {
   Respond(Error("Assistant service timed out"));
 }
 
+///////////////////////////////////////////////////////////////////////////////
+// AutotestPrivateEnableAssistantAndWaitForReadyFunction
+///////////////////////////////////////////////////////////////////////////////
+
+AutotestPrivateEnableAssistantAndWaitForReadyFunction::
+    AutotestPrivateEnableAssistantAndWaitForReadyFunction() = default;
+
+AutotestPrivateEnableAssistantAndWaitForReadyFunction::
+    ~AutotestPrivateEnableAssistantAndWaitForReadyFunction() {
+  ash::AssistantState::Get()->RemoveObserver(this);
+}
+
+ExtensionFunction::ResponseAction
+AutotestPrivateEnableAssistantAndWaitForReadyFunction::Run() {
+  DVLOG(1) << "AutotestPrivateEnableAssistantAndWaitForReadyFunction";
+
+  Profile* profile = Profile::FromBrowserContext(browser_context());
+  const std::string& err_msg =
+      SetWhitelistedPref(profile, chromeos::assistant::prefs::kAssistantEnabled,
+                         base::Value(true));
+  if (!err_msg.empty())
+    return RespondNow(Error(err_msg));
+
+  // Asynchronously subscribe to status changes to avoid a possible segmentation
+  // fault caused by Respond() in the subscriber callback being called before
+  // RespondLater() below.
+  PostTask(
+      FROM_HERE, {base::CurrentThread()},
+      base::BindOnce(&AutotestPrivateEnableAssistantAndWaitForReadyFunction::
+                         SubscribeToStatusChanges,
+                     this));
+
+  // Prevent |this| from being freed before we get a response from the
+  // Assistant.
+  self_ = this;
+
+  return RespondLater();
+}
+
+void AutotestPrivateEnableAssistantAndWaitForReadyFunction::
+    SubscribeToStatusChanges() {
+  // |AddObserver| will immediately trigger |OnAssistantStatusChanged|.
+  ash::AssistantState::Get()->AddObserver(this);
+}
+
+void AutotestPrivateEnableAssistantAndWaitForReadyFunction::
+    OnAssistantStatusChanged(ash::mojom::AssistantState state) {
+  if (state == ash::mojom::AssistantState::NEW_READY) {
+    Respond(NoArguments());
+    self_.reset();
+  }
+}
+
 // AssistantInteractionHelper is a helper class used to interact with Assistant
 // server and store interaction states for tests. It is shared by
 // |AutotestPrivateSendAssistantTextQueryFunction| and

chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.h

@@ -559,6 +559,29 @@ class AutotestPrivateSetAssistantEnabledFunction
   base::OneShotTimer timeout_timer_;
 };
 
+// Bring up the Assistant service, and wait until the ready signal is received.
+class AutotestPrivateEnableAssistantAndWaitForReadyFunction
+    : public ExtensionFunction,
+      public ash::AssistantStateObserver {
+ public:
+  AutotestPrivateEnableAssistantAndWaitForReadyFunction();
+  DECLARE_EXTENSION_FUNCTION("autotestPrivate.enableAssistantAndWaitForReady",
+                             AUTOTESTPRIVATE_ENABLEASSISTANTANDWAITFORREADY)
+
+ private:
+  ~AutotestPrivateEnableAssistantAndWaitForReadyFunction() override;
+  ResponseAction Run() override;
+
+  void SubscribeToStatusChanges();
+
+  // ash::AssistantStateObserver overrides:
+  void OnAssistantStatusChanged(ash::mojom::AssistantState state) override;
+
+  // A reference to keep |this| alive while waiting for the Assistant to
+  // respond.
+  scoped_refptr<ExtensionFunction> self_;
+};
+
 // Send text query to Assistant and return response.
 class AutotestPrivateSendAssistantTextQueryFunction : public ExtensionFunction {
  public:

chrome/common/extensions/api/autotest_private.idl

@@ -573,6 +573,10 @@ namespace autotestPrivate {
     static void setAssistantEnabled(boolean enabled, long timeout_ms,
                                     VoidCallback callback);
 
+    // Bring up the Assistant service, and wait for the ready signal.
+    // |callback|: Called when the operation has completed.
+    static void enableAssistantAndWaitForReady(VoidCallback callback);
+
     // Sends a text query via Google Assistant.
     // |callback|: Called when response has been received.
     static void sendAssistantTextQuery(DOMString query, long timeout_ms,

extensions/browser/extension_function_histogram_value.h

@@ -1465,6 +1465,7 @@ enum HistogramValue {
   AUTOTESTPRIVATE_ACTIVATEDESKATINDEX = 1402,
   AUTOTESTPRIVATE_REMOVEACTIVEDESK = 1403,
   TERMINALPRIVATE_GETCROSHSETTINGS = 1404,
+  AUTOTESTPRIVATE_ENABLEASSISTANTANDWAITFORREADY = 1405,
   // Last entry: Add new entries above, then run:
   // python tools/metrics/histograms/update_extension_histograms.py
   ENUM_BOUNDARY

tools/metrics/histograms/enums.xml

@@ -21253,6 +21253,7 @@ Called by update_net_error_codes.py.-->
   <int value="1402" label="AUTOTESTPRIVATE_ACTIVATEDESKATINDEX"/>
   <int value="1403" label="AUTOTESTPRIVATE_REMOVEACTIVEDESK"/>
   <int value="1404" label="TERMINALPRIVATE_GETCROSHSETTINGS"/>
+  <int value="1405" label="AUTOTESTPRIVATE_ENABLEASSISTANTANDWAITFORREADY"/>
 </enum>
 
 <enum name="ExtensionIconState">