Move MimeTypeResourceHandler before ThrottlingResourceHandler

content/browser/loader/intercepting_resource_handler_unittest.cc

Index: content/browser/loader/intercepting_resource_handler_unittest.cc
diff --git a/content/browser/loader/intercepting_resource_handler_unittest.cc b/content/browser/loader/intercepting_resource_handler_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..d2c55c28b46680c81531e5874f1249483739d142
--- /dev/null
+++ b/content/browser/loader/intercepting_resource_handler_unittest.cc
@@ -0,0 +1,153 @@
+// 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 "content/browser/loader/intercepting_resource_handler.h"
+
+#include <stdint.h>
+
+#include <memory>
+
+#include "base/files/file_path.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "content/public/browser/resource_controller.h"
+#include "content/public/browser/resource_request_info.h"
+#include "content/public/common/resource_response.h"
+#include "content/public/common/webplugininfo.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "content/public/test/test_utils.h"
+#include "net/url_request/url_request_context.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "url/gurl.h"
+
+namespace content {
+
+namespace {
+
+class TestResourceHandler : public ResourceHandler {
+ public:
+  TestResourceHandler()
+      : ResourceHandler(nullptr), buffer_(new net::IOBuffer(2048)) {}
+  ~TestResourceHandler() override {}
+
+  void SetController(ResourceController* controller) override {}
+
+  bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
+                           ResourceResponse* response,
+                           bool* defer) override {
+    NOTREACHED();
+    return false;
+  }
+
+  bool OnResponseStarted(ResourceResponse* response, bool* defer) override {
+    return true;
+  }
+
+  bool OnWillStart(const GURL& url, bool* defer) override { return false; }
+
+  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override {
+    NOTREACHED();
+    return false;
+  }
+
+  bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
+                  int* buf_size,
+                  int min_size) override {
+    *buf = buffer_;
+    *buf_size = 2048;
+    return true;
+  }
+
+  bool OnReadCompleted(int bytes_read, bool* defer) override {
+    DCHECK_LT(bytes_read, 2048);
+    return true;
+  }
+
+  void OnResponseCompleted(const net::URLRequestStatus& status,
+                           const std::string& security_info,
+                           bool* defer) override {}
+
+  void OnDataDownloaded(int bytes_downloaded) override { NOTREACHED(); }
+
+  scoped_refptr<net::IOBuffer> buffer() { return buffer_; }
+
+ private:
+  scoped_refptr<net::IOBuffer> buffer_;
+  DISALLOW_COPY_AND_ASSIGN(TestResourceHandler);
+};
+
+class InterceptingResourceHandlerTest : public testing::Test {
+ public:
+  InterceptingResourceHandlerTest() {}
+
+ private:
+  TestBrowserThreadBundle thread_bundle_;
+};
+
+// Tests that the data received is transmitted to the newly created
+// ResourceHandler.
+TEST_F(InterceptingResourceHandlerTest, ResponseBodyHandling) {
+  net::URLRequestContext context;
+  std::unique_ptr<net::URLRequest> request(context.CreateRequest(
+      GURL("http://www.google.com"), net::DEFAULT_PRIORITY, nullptr));
+  ResourceRequestInfo::AllocateForTesting(request.get(),
+                                          RESOURCE_TYPE_MAIN_FRAME,
+                                          nullptr,  // context
+                                          0,        // render_process_id
+                                          0,        // render_view_id
+                                          0,        // render_frame_id
+                                          true,     // is_main_frame
+                                          false,    // parent_is_main_frame
+                                          true,     // allow_download
+                                          true,     // is_async
+                                          false);   // is_using_lofi
+
+  std::unique_ptr<ResourceHandler> old_handler(new TestResourceHandler());
+  scoped_refptr<net::IOBuffer> old_buffer =
+      static_cast<TestResourceHandler*>(old_handler.get())->buffer();
+  std::unique_ptr<ResourceHandler> handler(
+      new InterceptingResourceHandler(std::move(old_handler), request.get()));
+  InterceptingResourceHandler* intercepting_handler =
+      static_cast<InterceptingResourceHandler*>(handler.get());
+
+  scoped_refptr<ResourceResponse> response(new ResourceResponse);
+
+  // Simulate the MimeSniffingResourceHandler buffering the data.
+  scoped_refptr<net::IOBuffer> read_buffer;
+  int buf_size = 0;
+  handler->OnWillRead(&read_buffer, &buf_size, -1);
+
+  char data[] = "The data";
+  CHECK_EQ(read_buffer.get(), old_buffer.get());
+  memcpy(read_buffer->data(), data, sizeof(data));
+
+  // Simulate the MimeSniffingResourceHandler asking the
+  // InterceptingResourceHandler to switch to a new handler.
+  std::unique_ptr<ResourceHandler> new_handler(new TestResourceHandler());
+  TestResourceHandler* new_test_handler =
+      static_cast<TestResourceHandler*>(new_handler.get());
+  intercepting_handler->UseNewHandler(std::move(new_handler), std::string());
+
+  // The response is received. The new ResourceHandler should be used handle
+  // the download.
+  bool defer = false;
+  handler->OnResponseStarted(response.get(), &defer);
+  EXPECT_FALSE(defer);
+
+  // It should not have received the download data yet.
+  EXPECT_FALSE(!memcmp(data, new_test_handler->buffer()->data(), sizeof(data)));
+
+  // The read is replayed by the MimeSniffingResourceHandler. The data should
+  // have been received by the new handler.
+  handler->OnReadCompleted(sizeof(data), &defer);
+  EXPECT_FALSE(defer);
+  EXPECT_TRUE(!memcmp(data, new_test_handler->buffer()->data(), sizeof(data)));
+}
+
+}  // namespace
+
+}  // namespace content