Fix autofill popup controller key press callback registration

components/autofill/content/browser/key_press_handler_manager_unittest.cc

+// 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 "components/autofill/content/browser/key_press_handler_manager.h"
+
+#include <string>
+
+#include "base/bind.h"
+#include "content/public/browser/native_web_keyboard_event.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace autofill {
+
+namespace {
+
+const content::NativeWebKeyboardEvent
+    kDummyEvent(blink::WebInputEvent::Undefined, 0, 0);
+
+// Dummy keyboard event handler: ignores the event, but appends the given |name|
+// to a logging |target|.
+bool DummyHandler(const char* name,
+                  std::string* target,
+                  const content::NativeWebKeyboardEvent& /*event*/) {
+  target->append(name);
+  return false;
+}
+
+// A delegate which logs the handlers instead of adding and removing them.
+class LoggingDelegate : public KeyPressHandlerManager::Delegate {
+ public:
+  explicit LoggingDelegate(std::string* target) : target_(target) {}
+
+  // KeyPressHandlerManager::Delegate:
+  void AddHandler(const content::RenderWidgetHost::KeyPressEventCallback&
+                      handler) override {
+    target_->append("A");
+    handler.Run(kDummyEvent);
+  }
+  void RemoveHandler(const content::RenderWidgetHost::KeyPressEventCallback&
+                         handler) override {
+    target_->append("R");
+    handler.Run(kDummyEvent);
+  }
+
+ private:
+  std::string* const target_;
+};
+
+}  // namespace
+
+class KeyPressHandlerManagerTest : public testing::Test {
+ public:
+  KeyPressHandlerManagerTest() : delegate_(&callback_trace_) {}
+
+ protected:
+  content::RenderWidgetHost::KeyPressEventCallback CallbackForName(
+      const char* name) {
+    return base::Bind(DummyHandler, name, &callback_trace_);
+  }
+
+  // String encoding the events related to adding and removing callbacks. For
+  // example, "A1R1A2R2" means that callback "1" was added, then removed, and
+  // then callback "2" was added and removed.
+  std::string callback_trace_;
+
+  LoggingDelegate delegate_;
+};
+
+// Removing should remove the previously added callback.
+TEST_F(KeyPressHandlerManagerTest, AddRemove) {
+  KeyPressHandlerManager manager(&delegate_);
+  manager.RegisterKeyPressHandler(CallbackForName("1"));
+  manager.RemoveKeyPressHandler();
+  EXPECT_EQ("A1R1", callback_trace_);
+}
+
+// Registering a new callback should remove the old one.
+TEST_F(KeyPressHandlerManagerTest, AddReplace) {
+  KeyPressHandlerManager manager(&delegate_);
+  manager.RegisterKeyPressHandler(CallbackForName("1"));
+  manager.RegisterKeyPressHandler(CallbackForName("2"));
+  manager.RemoveKeyPressHandler();
+  EXPECT_EQ("A1R1A2R2", callback_trace_);
+}
+
+// Without registering a callback first, none should be removed.
+TEST_F(KeyPressHandlerManagerTest, NoRemove) {
+  KeyPressHandlerManager manager(&delegate_);
+  manager.RemoveKeyPressHandler();
+  EXPECT_EQ(std::string(), callback_trace_);
+}
+
+// Adding one callback twice should be a no-op.
+TEST_F(KeyPressHandlerManagerTest, AddTwice) {
+  KeyPressHandlerManager manager(&delegate_);
+  auto callback = CallbackForName("1");
+  manager.RegisterKeyPressHandler(callback);
+  manager.RegisterKeyPressHandler(callback);
+  manager.RemoveKeyPressHandler();
+  EXPECT_EQ("A1R1", callback_trace_);
+}
+
+// Removing one callback twice should be a no-op.
+TEST_F(KeyPressHandlerManagerTest, RemoveTwice) {
+  KeyPressHandlerManager manager(&delegate_);
+  manager.RegisterKeyPressHandler(CallbackForName("1"));
+  manager.RemoveKeyPressHandler();
+  manager.RemoveKeyPressHandler();
+  EXPECT_EQ("A1R1", callback_trace_);
+}
+
+}  // namespace autofill