[Extensions Bindings] Add an ExceptionHandler class

extensions/renderer/bindings/api_request_handler_unittest.cc

 // 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 "extensions/renderer/bindings/api_request_handler.h"
+
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/optional.h"
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
 #include "extensions/renderer/bindings/api_binding_test.h"
 #include "extensions/renderer/bindings/api_binding_test_util.h"
-#include "extensions/renderer/bindings/api_request_handler.h"
+#include "extensions/renderer/bindings/exception_handler.h"
 #include "gin/converter.h"
 #include "gin/function_template.h"
 #include "gin/public/context_holder.h"
 #include "gin/public/isolate_holder.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "third_party/WebKit/public/web/WebScopedUserGesture.h"
 #include "third_party/WebKit/public/web/WebUserGestureIndicator.h"
 
 namespace extensions {
 
@@ skipping 17 matching lines @@
  public:
   // Runs the given |function|.
   void RunJS(v8::Local<v8::Function> function,
              v8::Local<v8::Context> context,
              int argc,
              v8::Local<v8::Value> argv[]) {
     RunFunctionOnGlobal(function, context, argc, argv);
     did_run_js_ = true;
   }
 
+  std::unique_ptr<APIRequestHandler> CreateRequestHandler() {
+    return base::MakeUnique<APIRequestHandler>(
+        base::Bind(&DoNothingWithRequest),
+        base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
+        APILastError(APILastError::GetParent(), binding::AddConsoleError()),
+        nullptr);
+  }
+
  protected:
   APIRequestHandlerTest() {}
   ~APIRequestHandlerTest() override {}
 
   bool did_run_js() const { return did_run_js_; }
 
  private:
   bool did_run_js_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(APIRequestHandlerTest);
 };
 
 // Tests adding a request to the request handler, and then triggering the
 // response.
 TEST_F(APIRequestHandlerTest, AddRequestAndCompleteRequestTest) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
-  EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
+  EXPECT_TRUE(request_handler->GetPendingRequestIdsForTesting().empty());
 
   v8::Local<v8::Function> function = FunctionFromString(context, kEchoArgs);
   ASSERT_FALSE(function.IsEmpty());
 
-  int request_id = request_handler.StartRequest(
+  int request_id = request_handler->StartRequest(
       context, kMethod, base::MakeUnique<base::ListValue>(), function,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_id));
 
   const char kArguments[] = "['foo',1,{'prop1':'bar'}]";
   std::unique_ptr<base::ListValue> response_arguments =
       ListValueFromString(kArguments);
   ASSERT_TRUE(response_arguments);
-  request_handler.CompleteRequest(request_id, *response_arguments,
-                                  std::string());
+  request_handler->CompleteRequest(request_id, *response_arguments,
+                                   std::string());
 
   EXPECT_TRUE(did_run_js());
   EXPECT_EQ(ReplaceSingleQuotes(kArguments),
             GetStringPropertyFromObject(context->Global(), context, "result"));
 
-  EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
+  EXPECT_TRUE(request_handler->GetPendingRequestIdsForTesting().empty());
 
-  request_id = request_handler.StartRequest(
+  request_id = request_handler->StartRequest(
       context, kMethod, base::MakeUnique<base::ListValue>(),
       v8::Local<v8::Function>(), v8::Local<v8::Function>(),
       binding::RequestThread::UI);
   EXPECT_NE(-1, request_id);
-  request_handler.CompleteRequest(request_id, base::ListValue(), std::string());
+  request_handler->CompleteRequest(request_id, base::ListValue(),
+                                   std::string());
 }
 
 // Tests that trying to run non-existent or invalided requests is a no-op.
 TEST_F(APIRequestHandlerTest, InvalidRequestsTest) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
   v8::Local<v8::Function> function = FunctionFromString(context, kEchoArgs);
   ASSERT_FALSE(function.IsEmpty());
 
-  int request_id = request_handler.StartRequest(
+  int request_id = request_handler->StartRequest(
       context, kMethod, base::MakeUnique<base::ListValue>(), function,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_id));
 
   std::unique_ptr<base::ListValue> response_arguments =
       ListValueFromString("['foo']");
   ASSERT_TRUE(response_arguments);
 
   // Try running with a non-existent request id.
   int fake_request_id = 42;
-  request_handler.CompleteRequest(fake_request_id, *response_arguments,
-                                  std::string());
+  request_handler->CompleteRequest(fake_request_id, *response_arguments,
+                                   std::string());
   EXPECT_FALSE(did_run_js());
 
   // Try running with a request from an invalidated context.
-  request_handler.InvalidateContext(context);
-  request_handler.CompleteRequest(request_id, *response_arguments,
-                                  std::string());
+  request_handler->InvalidateContext(context);
+  request_handler->CompleteRequest(request_id, *response_arguments,
+                                   std::string());
   EXPECT_FALSE(did_run_js());
 }
 
 TEST_F(APIRequestHandlerTest, MultipleRequestsAndContexts) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context_a = MainContext();
   v8::Local<v8::Context> context_b = AddContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
   // By having both different arguments and different behaviors in the
   // callbacks, we can easily verify that the right function is called in the
   // right context.
   v8::Local<v8::Function> function_a = FunctionFromString(
       context_a, "(function(res) { this.result = res + 'alpha'; })");
   v8::Local<v8::Function> function_b = FunctionFromString(
       context_b, "(function(res) { this.result = res + 'beta'; })");
 
-  int request_a = request_handler.StartRequest(
+  int request_a = request_handler->StartRequest(
       context_a, kMethod, base::MakeUnique<base::ListValue>(), function_a,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
-  int request_b = request_handler.StartRequest(
+  int request_b = request_handler->StartRequest(
       context_b, kMethod, base::MakeUnique<base::ListValue>(), function_b,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
 
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_a, request_b));
 
   std::unique_ptr<base::ListValue> response_a =
       ListValueFromString("['response_a:']");
   ASSERT_TRUE(response_a);
 
-  request_handler.CompleteRequest(request_a, *response_a, std::string());
+  request_handler->CompleteRequest(request_a, *response_a, std::string());
   EXPECT_TRUE(did_run_js());
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_b));
 
   EXPECT_EQ(
       ReplaceSingleQuotes("'response_a:alpha'"),
       GetStringPropertyFromObject(context_a->Global(), context_a, "result"));
 
   std::unique_ptr<base::ListValue> response_b =
       ListValueFromString("['response_b:']");
   ASSERT_TRUE(response_b);
 
-  request_handler.CompleteRequest(request_b, *response_b, std::string());
-  EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
+  request_handler->CompleteRequest(request_b, *response_b, std::string());
+  EXPECT_TRUE(request_handler->GetPendingRequestIdsForTesting().empty());
 
   EXPECT_EQ(
       ReplaceSingleQuotes("'response_b:beta'"),
       GetStringPropertyFromObject(context_b->Global(), context_b, "result"));
 }
 
 TEST_F(APIRequestHandlerTest, CustomCallbackArguments) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
   v8::Local<v8::Function> custom_callback =
       FunctionFromString(context, kEchoArgs);
   v8::Local<v8::Function> callback =
       FunctionFromString(context, "(function() {})");
   ASSERT_FALSE(callback.IsEmpty());
   ASSERT_FALSE(custom_callback.IsEmpty());
 
-  int request_id = request_handler.StartRequest(
+  int request_id = request_handler->StartRequest(
       context, "method", base::MakeUnique<base::ListValue>(), callback,
       custom_callback, binding::RequestThread::UI);
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_id));
 
   std::unique_ptr<base::ListValue> response_arguments =
       ListValueFromString("['response', 'arguments']");
   ASSERT_TRUE(response_arguments);
-  request_handler.CompleteRequest(request_id, *response_arguments,
-                                  std::string());
+  request_handler->CompleteRequest(request_id, *response_arguments,
+                                   std::string());
 
   EXPECT_TRUE(did_run_js());
   v8::Local<v8::Value> result =
       GetPropertyFromObject(context->Global(), context, "result");
   ASSERT_FALSE(result.IsEmpty());
   ASSERT_TRUE(result->IsArray());
   ArgumentList args;
   ASSERT_TRUE(gin::Converter<ArgumentList>::FromV8(isolate(), result, &args));
   ASSERT_EQ(5u, args.size());
   EXPECT_EQ("\"method\"", V8ToString(args[0], context));
   EXPECT_EQ(base::StringPrintf("{\"id\":%d}", request_id),
             V8ToString(args[1], context));
   EXPECT_EQ(callback, args[2]);
   EXPECT_EQ("\"response\"", V8ToString(args[3], context));
   EXPECT_EQ("\"arguments\"", V8ToString(args[4], context));
 
-  EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
+  EXPECT_TRUE(request_handler->GetPendingRequestIdsForTesting().empty());
 }
 
 // Test that having a custom callback without an extension-provided callback
 // doesn't crash.
 TEST_F(APIRequestHandlerTest, CustomCallbackArgumentsWithEmptyCallback) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
   v8::Local<v8::Function> custom_callback =
       FunctionFromString(context, kEchoArgs);
   ASSERT_FALSE(custom_callback.IsEmpty());
 
   v8::Local<v8::Function> empty_callback;
-  int request_id = request_handler.StartRequest(
+  int request_id = request_handler->StartRequest(
       context, "method", base::MakeUnique<base::ListValue>(), empty_callback,
       custom_callback, binding::RequestThread::UI);
-  EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
+  EXPECT_THAT(request_handler->GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_id));
 
-  request_handler.CompleteRequest(request_id, base::ListValue(), std::string());
+  request_handler->CompleteRequest(request_id, base::ListValue(),
+                                   std::string());
 
   EXPECT_TRUE(did_run_js());
   v8::Local<v8::Value> result =
       GetPropertyFromObject(context->Global(), context, "result");
   ASSERT_FALSE(result.IsEmpty());
   ASSERT_TRUE(result->IsArray());
   ArgumentList args;
   ASSERT_TRUE(gin::Converter<ArgumentList>::FromV8(isolate(), result, &args));
   ASSERT_EQ(3u, args.size());
   EXPECT_EQ("\"method\"", V8ToString(args[0], context));
   EXPECT_EQ(base::StringPrintf("{\"id\":%d}", request_id),
             V8ToString(args[1], context));
   EXPECT_TRUE(args[2]->IsUndefined());
 
-  EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
+  EXPECT_TRUE(request_handler->GetPendingRequestIdsForTesting().empty());
 }
 
 // Test user gestures being curried around for API requests.
 TEST_F(APIRequestHandlerTest, UserGestureTest) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
-  APIRequestHandler request_handler(
-      base::Bind(&DoNothingWithRequest),
-      base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+  std::unique_ptr<APIRequestHandler> request_handler = CreateRequestHandler();
 
   auto callback = [](base::Optional<bool>* ran_with_user_gesture) {
     *ran_with_user_gesture =
         blink::WebUserGestureIndicator::IsProcessingUserGestureThreadSafe();
   };
 
   // Set up a callback to be used with the request so we can check if a user
   // gesture was active.
   base::Optional<bool> ran_with_user_gesture;
   v8::Local<v8::FunctionTemplate> function_template =
       gin::CreateFunctionTemplate(isolate(),
                                   base::Bind(callback, &ran_with_user_gesture));
   v8::Local<v8::Function> v8_callback =
       function_template->GetFunction(context).ToLocalChecked();
 
   // Try first without a user gesture.
-  int request_id = request_handler.StartRequest(
+  int request_id = request_handler->StartRequest(
       context, kMethod, base::MakeUnique<base::ListValue>(), v8_callback,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
-  request_handler.CompleteRequest(request_id, *ListValueFromString("[]"),
-                                  std::string());
+  request_handler->CompleteRequest(request_id, *ListValueFromString("[]"),
+                                   std::string());
 
   ASSERT_TRUE(ran_with_user_gesture);
   EXPECT_FALSE(*ran_with_user_gesture);
   ran_with_user_gesture.reset();
 
   // Next try calling with a user gesture. Since a gesture will be active at the
   // time of the call, it should also be active during the callback.
   {
     blink::WebScopedUserGesture user_gesture(nullptr);
     EXPECT_TRUE(
         blink::WebUserGestureIndicator::IsProcessingUserGestureThreadSafe());
-    request_id = request_handler.StartRequest(
+    request_id = request_handler->StartRequest(
         context, kMethod, base::MakeUnique<base::ListValue>(), v8_callback,
         v8::Local<v8::Function>(), binding::RequestThread::UI);
   }
   EXPECT_FALSE(
       blink::WebUserGestureIndicator::IsProcessingUserGestureThreadSafe());
 
-  request_handler.CompleteRequest(request_id, *ListValueFromString("[]"),
-                                  std::string());
+  request_handler->CompleteRequest(request_id, *ListValueFromString("[]"),
+                                   std::string());
   ASSERT_TRUE(ran_with_user_gesture);
   EXPECT_TRUE(*ran_with_user_gesture);
   // Sanity check - after the callback ran, there shouldn't be an active
   // gesture.
   EXPECT_FALSE(
       blink::WebUserGestureIndicator::IsProcessingUserGestureThreadSafe());
 }
 
 TEST_F(APIRequestHandlerTest, RequestThread) {
   v8::HandleScope handle_scope(isolate());
   v8::Local<v8::Context> context = MainContext();
 
   base::Optional<binding::RequestThread> thread;
   auto on_request = [](base::Optional<binding::RequestThread>* thread_out,
                        std::unique_ptr<APIRequestHandler::Request> request,
                        v8::Local<v8::Context> context) {
     *thread_out = request->thread;
   };
 
   APIRequestHandler request_handler(
       base::Bind(on_request, &thread),
       base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+      APILastError(APILastError::GetParent(), binding::AddConsoleError()),
+      nullptr);
 
   request_handler.StartRequest(
       context, kMethod, base::MakeUnique<base::ListValue>(),
       v8::Local<v8::Function>(), v8::Local<v8::Function>(),
       binding::RequestThread::UI);
   ASSERT_TRUE(thread);
   EXPECT_EQ(binding::RequestThread::UI, *thread);
   thread.reset();
 
   request_handler.StartRequest(
@@ skipping 16 matching lines @@
   };
 
   auto log_error = [](base::Optional<std::string>* logged_error,
                       v8::Local<v8::Context> context,
                       const std::string& error) { *logged_error = error; };
 
   APIRequestHandler request_handler(
       base::Bind(&DoNothingWithRequest),
       base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
       APILastError(base::Bind(get_parent),
-                   base::Bind(log_error, &logged_error)));
+                   base::Bind(log_error, &logged_error)),
+      nullptr);
 
   const char kReportExposedLastError[] =
       "(function() {\n"
       "  if (this.lastError)\n"
       "    this.seenLastError = this.lastError.message;\n"
       "})";
   auto get_exposed_error = [context]() {
     return GetStringPropertyFromObject(context->Global(), context,
                                        "seenLastError");
   };
@@ skipping 52 matching lines @@
   bool dispatched_request = false;
   auto handle_request = [](bool* dispatched_request,
                            std::unique_ptr<APIRequestHandler::Request> request,
                            v8::Local<v8::Context> context) {
     *dispatched_request = true;
   };
 
   APIRequestHandler request_handler(
       base::Bind(handle_request, &dispatched_request),
       base::Bind(&APIRequestHandlerTest::RunJS, base::Unretained(this)),
-      APILastError(APILastError::GetParent(), APILastError::AddConsoleError()));
+      APILastError(APILastError::GetParent(), binding::AddConsoleError()),
+      nullptr);
 
   EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
   v8::Local<v8::Function> function = FunctionFromString(context, kEchoArgs);
   ASSERT_FALSE(function.IsEmpty());
 
   int request_id = request_handler.AddPendingRequest(context, function);
   EXPECT_THAT(request_handler.GetPendingRequestIdsForTesting(),
               testing::UnorderedElementsAre(request_id));
   // Even though we add a pending request, we shouldn't have dispatched anything
   // because AddPendingRequest() is intended for renderer-side implementations.
   EXPECT_FALSE(dispatched_request);
 
   const char kArguments[] = "['foo',1,{'prop1':'bar'}]";
   std::unique_ptr<base::ListValue> response_arguments =
       ListValueFromString(kArguments);
   ASSERT_TRUE(response_arguments);
   request_handler.CompleteRequest(request_id, *response_arguments,
                                   std::string());
 
   EXPECT_EQ(ReplaceSingleQuotes(kArguments),
             GetStringPropertyFromObject(context->Global(), context, "result"));
 
   EXPECT_TRUE(request_handler.GetPendingRequestIdsForTesting().empty());
   EXPECT_FALSE(dispatched_request);
 }
 
+// Tests that throwing an exception in a callback is properly handled.
+TEST_F(APIRequestHandlerTest, ThrowExceptionInCallback) {
+  v8::HandleScope handle_scope(isolate());
+  v8::Local<v8::Context> context = MainContext();
+
+  auto add_console_error = [](base::Optional<std::string>* error_out,
+                              v8::Local<v8::Context> context,
+                              const std::string& error) { *error_out = error; };
+
+  // RunFunction* from the test util assert no errors; provide a version that
+  // allows them.
+  auto run_function_and_allow_errors =
+      [](v8::Local<v8::Function> function, v8::Local<v8::Context> context,
+         int argc, v8::Local<v8::Value> argv[]) {
+        ignore_result(function->Call(context, context->Global(), argc, argv));
+      };
+
+  base::Optional<std::string> logged_error;
+  ExceptionHandler exception_handler(
+      base::Bind(add_console_error, &logged_error),
+      base::Bind(&RunFunctionOnGlobalAndIgnoreResult));
+
+  APIRequestHandler request_handler(
+      base::Bind(&DoNothingWithRequest),
+      base::Bind(run_function_and_allow_errors),
+      APILastError(APILastError::GetParent(), binding::AddConsoleError()),
+      &exception_handler);
+
+  v8::TryCatch try_catch(isolate());
+  v8::Local<v8::Function> callback_throwing_error =
+      FunctionFromString(context, "(function() { throw new Error('hello'); })");
+  int request_id =
+      request_handler.AddPendingRequest(context, callback_throwing_error);
+  request_handler.CompleteRequest(request_id, base::ListValue(), std::string());
+  // The outer TryCatch should not be caught. This is important to not disrupt

[lazyboy, 2017/07/10 23:12:08]

Add a bit more context about the try catch you're referring to here, may be call
it |outer_try_catch| or similar. It's not immediately noticeable what the inner
try catch is... so maybe something along the line of "The inner try catch inside
|exception_handler| should be caught, but not the outer try catch".

[Devlin, 2017/07/11 17:33:35]

Done.

+  // our bindings code (or other running JS) when asynchronously returning from
+  // an API call.
+  EXPECT_FALSE(try_catch.HasCaught());
+  ASSERT_TRUE(logged_error);
+  EXPECT_EQ("Error handling response: Uncaught Error: hello", *logged_error);
+}
+
 }  // namespace extensions