Refactor Blink's ServiceConnector and add ability to mock in layout tests

content/renderer/mojo/blink_connector_impl_unittest.cc

Index: content/renderer/mojo/blink_connector_impl_unittest.cc
diff --git a/content/renderer/mojo/blink_connector_impl_unittest.cc b/content/renderer/mojo/blink_connector_impl_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e30a3bb90b1c1a04f26925d8803146d0634ef1f4
--- /dev/null
+++ b/content/renderer/mojo/blink_connector_impl_unittest.cc
@@ -0,0 +1,158 @@
+// Copyright 2017 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 "content/renderer/mojo/blink_connector_impl.h"
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "services/service_manager/public/cpp/connector.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+
+namespace {
+class MockConnector : public service_manager::Connector {
+ public:
+  MockConnector(int* foo_baz_impl_requests, int* bar_baz_impl_requests)
+      : foo_baz_impl_requests_(foo_baz_impl_requests),
+        bar_baz_impl_requests_(bar_baz_impl_requests),
+        weak_factory_(this) {}
+
+  // Connector:
+  void StartService(const service_manager::Identity& identity,
+                    service_manager::mojom::ServicePtr service,
+                    service_manager::mojom::PIDReceiverRequest
+                        pid_receiver_request) override {}
+  std::unique_ptr<service_manager::Connection> Connect(
+      const std::string& name) override {
+    return nullptr;
+  }
+  std::unique_ptr<service_manager::Connection> Connect(
+      const service_manager::Identity& target) override {
+    return nullptr;
+  }
+  void BindInterface(const service_manager::Identity& target,
+                     const std::string& interface_name,
+                     mojo::ScopedMessagePipeHandle interface_pipe) override;
+  std::unique_ptr<Connector> Clone() override { return nullptr; }
+  void BindConnectorRequest(
+      service_manager::mojom::ConnectorRequest request) override {}
+  base::WeakPtr<Connector> GetWeakPtr() override {
+    return weak_factory_.GetWeakPtr();
+  }
+
+ protected:
+  void OverrideBinderForTesting(const std::string& interface_name,
+                                const TestApi::Binder& binder) override {}
+  void ClearBinderOverrides() override {}
+
+ private:
+  int* foo_baz_impl_requests_;
+  int* bar_baz_impl_requests_;
+  base::WeakPtrFactory<MockConnector> weak_factory_;
+};
+
+void MockConnector::BindInterface(
+    const service_manager::Identity& target,
+    const std::string& interface_name,
+    mojo::ScopedMessagePipeHandle interface_pipe) {
+  if (target.name() == "foo" && interface_name == "baz") {
+    (*foo_baz_impl_requests_)++;
+    return;
+  }
+
+  if (target.name() == "bar" && interface_name == "baz") {
+    (*bar_baz_impl_requests_)++;
+    return;
+  }
+
+  NOTREACHED();
+}
+
+}  // namespace
+
+class BlinkConnectorImplTest : public testing::Test {
+ public:
+  BlinkConnectorImplTest()
+      : foo_baz_impl_requests_(0),
+        bar_baz_impl_requests_(0),
+        foo_baz_override_requests_(0),
+        bar_baz_override_requests_(0),
+        connector_(base::MakeUnique<MockConnector>(&foo_baz_impl_requests_,
+                                                   &bar_baz_impl_requests_)) {}
+
+  void OverrideFooBaz(mojo::ScopedMessagePipeHandle interface_pipe) {
+    foo_baz_override_requests_++;
+  }
+
+  void OverrideBarBaz(mojo::ScopedMessagePipeHandle interface_pipe) {
+    bar_baz_override_requests_++;
+  }
+
+ protected:
+  BlinkConnectorImpl* connector() { return &connector_; }
+  int foo_baz_impl_requests() { return foo_baz_impl_requests_; }
+  int bar_baz_impl_requests() { return bar_baz_impl_requests_; }
+  int foo_baz_override_requests() { return foo_baz_override_requests_; }
+  int bar_baz_override_requests() { return bar_baz_override_requests_; }
+
+ private:
+  base::MessageLoop loop_;
+  int foo_baz_impl_requests_;
+  int bar_baz_impl_requests_;
+  int foo_baz_override_requests_;
+  int bar_baz_override_requests_;
+  BlinkConnectorImpl connector_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlinkConnectorImplTest);
+};
+
+TEST_F(BlinkConnectorImplTest, Basic) {
+  EXPECT_EQ(0, foo_baz_impl_requests());
+  EXPECT_EQ(0, bar_baz_impl_requests());
+
+  mojo::MessagePipe pipe1;
+  connector()->bindInterface("foo", "baz", std::move(pipe1.handle0));
+  EXPECT_EQ(1, foo_baz_impl_requests());
+  EXPECT_EQ(0, bar_baz_impl_requests());
+
+  mojo::MessagePipe pipe2;
+  connector()->bindInterface("bar", "baz", std::move(pipe2.handle0));
+  EXPECT_EQ(1, foo_baz_impl_requests());
+  EXPECT_EQ(1, bar_baz_impl_requests());
+}
+
+TEST_F(BlinkConnectorImplTest, Override) {
+  EXPECT_EQ(0, foo_baz_impl_requests());
+  EXPECT_EQ(0, foo_baz_override_requests());
+  EXPECT_EQ(0, bar_baz_impl_requests());
+
+  connector()->AddOverrideForTesting(
+      "foo", "baz",
+      base::Bind(&BlinkConnectorImplTest::OverrideFooBaz,
+                 base::Unretained(this)));
+
+  mojo::MessagePipe pipe1;
+  connector()->bindInterface("foo", "baz", std::move(pipe1.handle0));
+  EXPECT_EQ(0, foo_baz_impl_requests());
+  EXPECT_EQ(1, foo_baz_override_requests());
+  EXPECT_EQ(0, bar_baz_impl_requests());
+
+  mojo::MessagePipe pipe2;
+  connector()->bindInterface("bar", "baz", std::move(pipe2.handle0));
+  EXPECT_EQ(0, foo_baz_impl_requests());
+  EXPECT_EQ(1, foo_baz_override_requests());
+  EXPECT_EQ(1, bar_baz_impl_requests());
+
+  connector()->ClearOverridesForTesting();
+
+  mojo::MessagePipe pipe3;
+  connector()->bindInterface("foo", "baz", std::move(pipe3.handle0));
+  EXPECT_EQ(1, foo_baz_impl_requests());
+  EXPECT_EQ(1, foo_baz_override_requests());
+  EXPECT_EQ(1, bar_baz_impl_requests());
+}
+
+}  // namespace content