Merge TestResourceHandlers used by two different test fixtures.

content/browser/loader/test_resource_handler.h

+// 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.
+
+#ifndef CONTENT_BROWSER_LOADER_TEST_RESOURCE_HANDLER_H_
+#define CONTENT_BROWSER_LOADER_TEST_RESOURCE_HANDLER_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "content/browser/loader/resource_handler.h"
+#include "net/base/io_buffer.h"
+
+class GURL;

[Charlie Harrison, 2016/10/26 14:05:19]

ResourceHandler forward declares this already, so you can probably omit this as
a subclass.

[mmenke, 2016/10/26 15:27:29]

I'd argue it's better to be comprehensive, and forward declare it.  Imagine, for
instance, we remove it, and then add some other dependency on GURL being forward
declared to this file.  Then we decide not to make this a ResourceHandler any
more, and get rid of that include.  We're suddenly just removing code, but have
to add a forward declaration because we're moving a not-clearly-related header.

That's not likely to happen in this case, but in general, it does happen, so
think it's best to be explicit about forward declaration to avoid IWYU issues
going forward.

+
+namespace net {
+class URLRequest;
+class URLRequestStatus;
+}
+
+namespace content {
+
+class ResourceHandler;
+struct ResourceResponse;
+
+// A test version of a ResourceHandler. It returns a configurable buffer in
+// response to OnWillStart. It records what ResourceHandler methods are called,
+// and verifies that they are called in the correct order. It can optionally
+// defer or fail the request at any stage, and record the response body and
+// final status it sees. Redirects currently not supported.
+class TestResourceHandler : public ResourceHandler {

[mmenke, 2016/10/25 14:59:06]

Note that this is just the TestResourceHandler from
intercepting_resource_handler_unittest.cc, with a couple changes (ints instead
of bools, request_state/body are optional, some getters added, on_read calls
counted, may be leaving out one or two).

I'd suggest just comparing this with the old one side-by-side.  Reducing the
similarity threshold myself doesn't work, unfortunately, it ends up with the
MojoAsyncResourceHandler header as being more similar.

+ public:
+  // If non-null, |request_status| will be updated when the response is complete
+  // with the final status of the request received by the handler and |body|
+  // will be updated on each OnReadCompleted call.
+  TestResourceHandler(net::URLRequestStatus* request_status, std::string* body);
+  TestResourceHandler();
+  ~TestResourceHandler() override;
+
+  // ResourceHandler implementation:
+  void SetController(ResourceController* controller) override;
+  bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
+                           ResourceResponse* response,
+                           bool* defer) override;
+  bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
+  bool OnWillStart(const GURL& url, bool* defer) override;
+  bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
+                  int* buf_size,
+                  int min_size) override;
+  bool OnReadCompleted(int bytes_read, bool* defer) override;
+  void OnResponseCompleted(const net::URLRequestStatus& status,
+                           bool* defer) override;
+  void OnDataDownloaded(int bytes_downloaded) override;
+
+  // Sets the size of the read buffer returned by OnWillRead. Releases reference
+  // to previous read buffer. Default size is 2048 bytes.
+  void SetBufferSize(int buffer_size);
+
+  scoped_refptr<net::IOBuffer> buffer() const { return buffer_; }
+
+  // Sets the result returned by each method. All default to returning true.
+  void set_on_will_start_result(bool on_will_start_result) {
+    on_will_start_result_ = on_will_start_result;
+  }
+  void set_on_response_started_result(bool on_response_started_result) {
+    on_response_started_result_ = on_response_started_result;
+  }
+  void set_on_will_read_result(bool on_will_read_result) {
+    on_will_read_result_ = on_will_read_result;
+  }
+  void set_on_read_completed_result(bool on_read_completed_result) {
+    on_read_completed_result_ = on_read_completed_result;
+  }
+
+  // Cause |defer| to be set to true when the specified method is invoked. The
+  // test itself is responsible for resuming the request after deferral.
+
+  void set_defer_on_will_start(bool defer_on_will_start) {
+    defer_on_will_start_ = defer_on_will_start;
+  }
+  void set_defer_on_response_started(bool defer_on_response_started) {
+    defer_on_response_started_ = defer_on_response_started;
+  }
+  // Only the next OnReadCompleted call will set |defer| to true.
+  void set_defer_on_read_completed(bool defer_on_read_completed) {
+    defer_on_read_completed_ = defer_on_read_completed;
+  }
+  void set_defer_on_response_completed(bool defer_on_response_completed) {
+    defer_on_response_completed_ = defer_on_response_completed;
+  }
+
+  // Return the number of times the corresponding method was invoked.
+
+  int on_will_start_called() const { return on_will_start_called_; }
+  // Redirection currently not supported.
+  int on_request_redirected_called() const { return 0; }
+  int on_response_started_called() const { return on_response_started_called_; }
+  int on_will_read_called() const { return on_will_read_called_; }
+  int on_read_completed_called() const { return on_read_completed_called_; }
+  int on_response_completed_called() const {
+    return on_response_completed_called_;
+  }
+
+ private:
+  net::URLRequestStatus* request_status_;
+  std::string* body_;
+  scoped_refptr<net::IOBuffer> buffer_;
+  size_t buffer_size_;
+
+  bool on_will_start_result_ = true;
+  bool on_response_started_result_ = true;
+  bool on_will_read_result_ = true;
+  bool on_read_completed_result_ = true;
+
+  bool defer_on_will_start_ = false;
+  bool defer_on_response_started_ = false;
+  bool defer_on_read_completed_ = false;
+  bool defer_on_response_completed_ = false;
+
+  int on_will_start_called_ = 0;
+  int on_response_started_called_ = 0;
+  int on_will_read_called_ = 0;
+  int on_read_completed_called_ = 0;
+  int on_response_completed_called_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(TestResourceHandler);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_LOADER_TEST_RESOURCE_HANDLER_H_