[ios Mojo] Integration test for Mojo WebUI.

ios/web/webui/web_ui_mojo_inttest.mm

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <memory>
+
+#include "base/run_loop.h"
+#import "base/test/ios/wait_util.h"
+#include "ios/public/provider/web/web_ui_ios_controller.h"
+#include "ios/public/provider/web/web_ui_ios_controller_factory.h"
+#import "ios/web/public/navigation_manager.h"
+#include "ios/web/public/web_ui_ios_data_source.h"
+#include "ios/web/test/grit/test_resources.h"
+#include "ios/web/test/mojo_test.mojom.h"
+#include "ios/web/test/test_url_constants.h"
+#import "ios/web/test/web_int_test.h"
+#import "ios/web/web_state/web_state_impl.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+#include "services/shell/public/cpp/interface_registry.h"
+#include "url/gurl.h"
+#include "url/scheme_host_port.h"
+
+namespace web {
+
+namespace {
+
+// Hostname for test WebUI page.
+const char kTestWebUIURLHost[] = "testwebui";
+
+// UI handler class which communicates with test WebUI page as follows:
+// - page sends "syn" message to |TestUIHandler|
+// - |TestUIHandler| replies with "ack" message
+// - page replies back with "fin"
+//
+// Once "fin" is received |IsFinReceived()| call will return true, indicating
+// that communication was successfull. See test WebUI page for more details:

[Jackie Quinn, 2016/05/27 01:03:41]

s/successfull/successful 

[Eugene But (OOO till 7-30), 2016/05/27 15:29:00]

Done.

+// ios/web/test/data/mojo_test.js

[Jackie Quinn, 2016/05/27 01:03:41]

You've got a circular reference here, since mojo_test.js points to this file for
"more detailed documentation." 

One could argue that by "more details," you mean "read the code." Maybe you
could say "See test WebUI page for implementation details," or something to that
effect. 

[Eugene But (OOO till 7-30), 2016/05/27 15:29:00]

Done.

+class TestUIHandler : public TestUIHandlerMojo,
+                      public shell::InterfaceFactory<TestUIHandlerMojo> {
+ public:
+  TestUIHandler() {}
+  ~TestUIHandler() override {}
+
+  // Returns true if "fin" has been received.
+  bool IsFinReceived() { return fin_received_; }
+
+  // TestUIHandlerMojo overrides.
+  void HandleJsMessage(const mojo::String& message, TestPagePtr page) override {
+    if (message.get() == "syn") {
+      // Received "syn" message from WebUI page, send "ack" as reply.
+      DCHECK(!syn_received_);
+      DCHECK(!fin_received_);
+      syn_received_ = true;
+      NativeMessageResultMojoPtr result(NativeMessageResultMojo::New());
+      result->message = mojo::String::From("ack");
+      page->HandleNativeMessage(std::move(result));
+    } else if (message.get() == "fin") {
+      // Received "fin" from the WebUI page in response to "ack".
+      DCHECK(syn_received_);
+      DCHECK(!fin_received_);
+      fin_received_ = true;
+    } else {
+      NOTREACHED();
+    }
+  }
+
+ private:
+  // shell::InterfaceFactory overrides.
+  void Create(shell::Connection* connection,
+              mojo::InterfaceRequest<TestUIHandlerMojo> request) override {
+    bindings_.AddBinding(this, std::move(request));
+  }
+
+  mojo::BindingSet<TestUIHandlerMojo> bindings_;
+  // |true| if "syn" has been received.
+  bool syn_received_ = false;
+  // |true| if "fin" has been received.
+  bool fin_received_ = false;
+};
+
+// Controller for test WebUI.
+class TestUI : public WebUIIOSController {
+ public:
+  // Constructs controller from |web_ui| and |ui_handler| which will communicate
+  // with test WebUI page.
+  TestUI(WebUIIOS* web_ui, TestUIHandler* ui_handler)
+      : WebUIIOSController(web_ui) {
+    web::WebUIIOSDataSource* source =
+        web::WebUIIOSDataSource::Create(kTestWebUIURLHost);
+
+    source->AddResourcePath("mojo_test.js", IDR_MOJO_TEST_JS);
+    source->AddResourcePath("ios/web/test/mojo_test.mojom",
+                            IDR_MOJO_TEST_MOJO_JS);
+    source->SetDefaultResource(IDR_MOJO_TEST_HTML);
+
+    web::WebState* web_state = web_ui->GetWebState();
+    web::WebUIIOSDataSource::Add(web_state->GetBrowserState(), source);
+
+    web_state->GetMojoInterfaceRegistry()->AddInterface(ui_handler);
+  }
+};
+
+// Factory that creates TestUI controller.
+class TestWebUIControllerFactory : public WebUIIOSControllerFactory {
+ public:
+  // Constructs a controller factory which will eventually create |ui_handler|.
+  explicit TestWebUIControllerFactory(TestUIHandler* ui_handler)
+      : ui_handler_(ui_handler) {}
+
+  // WebUIIOSControllerFactory overrides.
+  WebUIIOSController* CreateWebUIIOSControllerForURL(
+      WebUIIOS* web_ui,
+      const GURL& url) const override {
+    DCHECK_EQ(url.scheme(), kTestWebUIScheme);
+    DCHECK_EQ(url.host(), kTestWebUIURLHost);
+    return new TestUI(web_ui, ui_handler_);
+  }
+
+ private:
+  // UI handler class which communicates with test WebUI page.
+  TestUIHandler* ui_handler_;
+};
+}  // namespace
+
+// A test fixture for verifying mojo comminication for WebUI.
+class WebUIMojoTest : public WebIntTest {
+ protected:
+  WebUIMojoTest()
+      : web_state_(new WebStateImpl(GetBrowserState())),
+        ui_handler_(new TestUIHandler()) {
+    web_state_->GetNavigationManagerImpl().InitializeSession(nil, nil, NO, 0);
+    WebUIIOSControllerFactory::RegisterFactory(
+        new TestWebUIControllerFactory(ui_handler_.get()));
+  }
+
+  // Returns WebState which loads test WebUI page.
+  WebStateImpl* web_state() { return web_state_.get(); }
+  // Returns UI handler which communicates with WebUI page.
+  TestUIHandler* test_ui_handler() { return ui_handler_.get(); }
+
+ private:
+  std::unique_ptr<WebStateImpl> web_state_;
+  std::unique_ptr<TestUIHandler> ui_handler_;
+};
+
+// Tests that JS can send messages to the native code and vice versa.
+// TestUIHandler is used for communication and test suceeds only when
+// |TestUIHandler| sucessfully receives "ack" message from WebUI page.
+TEST_F(WebUIMojoTest, MessageExchange) {
+  web_state()->SetWebUsageEnabled(true);
+  web_state()->GetWebController().useMojoForWebUI = YES;
+  web_state()->GetView();  // WebState won't load URL without view.
+  NavigationManager::WebLoadParams load_params(GURL(
+      url::SchemeHostPort(kTestWebUIScheme, kTestWebUIURLHost, 0).Serialize()));
+  web_state()->GetNavigationManager()->LoadURLWithParams(load_params);
+
+  // Wait until |TestUIHandler| receives "ack" message from WebUI page.
+  base::test::ios::WaitUntilCondition(^{
+    base::RunLoop().RunUntilIdle();
+    return test_ui_handler()->IsFinReceived();
+  });
+}
+
+}  // namespace web