Split ScriptStreamer and ScriptStreamerImpl, preparing for unit testing

third_party/WebKit/Source/bindings/core/v8/ScriptStreamerImpl.h

 // Copyright 2014 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 ScriptStreamer_h
-#define ScriptStreamer_h
+#ifndef ScriptStreamerImpl_h
+#define ScriptStreamerImpl_h
 
 #include <memory>
 
+#include "bindings/core/v8/ScriptStreamer.h"
 #include "core/CoreExport.h"
 #include "platform/heap/Handle.h"
 #include "platform/wtf/Noncopyable.h"
 #include "platform/wtf/text/WTFString.h"
 #include "v8/include/v8.h"
 
 namespace blink {
 
 class PendingScript;
 class Resource;
 class ScriptResource;
 class ScriptState;
 class Settings;
 class SourceStream;
 class WebTaskRunner;
 
-// ScriptStreamer streams incomplete script data to V8 so that it can be parsed
-// while it's loaded. PendingScript holds a reference to ScriptStreamer. At the
-// moment, ScriptStreamer is only used for parser blocking scripts; this means
-// that the Document stays stable and no other scripts are executing while we're
-// streaming. It is possible, though, that Document and the PendingScript are
-// destroyed while the streaming is in progress, and ScriptStreamer handles it
-// gracefully.
-class CORE_EXPORT ScriptStreamer final
-    : public GarbageCollectedFinalized<ScriptStreamer> {
-  WTF_MAKE_NONCOPYABLE(ScriptStreamer);
+class CORE_EXPORT ScriptStreamerImpl final : public ScriptStreamer {
+  WTF_MAKE_NONCOPYABLE(ScriptStreamerImpl);
 
  public:
-  enum Type { kParsingBlocking, kDeferred, kAsync };
-
-  ~ScriptStreamer();
+  ~ScriptStreamerImpl();
   DECLARE_TRACE();
 
   // Launches a task (on a background thread) which will stream the given
   // PendingScript into V8 as it loads.
   static void StartStreaming(PendingScript*,
                              Type,
                              Settings*,
                              ScriptState*,
                              RefPtr<WebTaskRunner>);
 
   // Returns false if we cannot stream the given encoding.
   static bool ConvertEncoding(const char* encoding_name,
                               v8::ScriptCompiler::StreamedSource::Encoding*);
 
-  bool IsFinished() const;
+  v8::ScriptCompiler::StreamedSource* Source() override {
+    return source_.get();
+  }
+  ScriptResource* GetResource() const override { return resource_; }
 
-  v8::ScriptCompiler::StreamedSource* Source() { return source_.get(); }
-  ScriptResource* GetResource() const { return resource_; }
-
-  // Called when the script is not needed any more (e.g., loading was
-  // cancelled). After calling cancel, PendingScript can drop its reference to
-  // ScriptStreamer, and ScriptStreamer takes care of eventually deleting
-  // itself (after the V8 side has finished too).
-  void Cancel();
-
-  // When the streaming is suppressed, the data is not given to V8, but
-  // ScriptStreamer still watches the resource load and notifies the upper
-  // layers when loading is finished. It is used in situations when we have
-  // started streaming but then we detect we don't want to stream (e.g., when
-  // we have the code cache for the script) and we still want to parse and
-  // execute it when it has finished loading.
   void SuppressStreaming();
-  bool StreamingSuppressed() const { return streaming_suppressed_; }
-
-  // Called by PendingScript when data arrives from the network.
-  void NotifyAppendData(ScriptResource*);
-  void NotifyFinished(Resource*);
 
   // Called by ScriptStreamingTask when it has streamed all data to V8 and V8
   // has processed it.
   void StreamingCompleteOnBackgroundThread();
 
   const String& ScriptURLString() const { return script_url_string_; }
   unsigned long ScriptResourceIdentifier() const {
     return script_resource_identifier_;
   }
 
   static void SetSmallScriptThresholdForTesting(size_t threshold) {
     small_script_threshold_ = threshold;
   }
 
  private:
   // Scripts whose first data chunk is smaller than this constant won't be
   // streamed. Non-const for testing.
   static size_t small_script_threshold_;
 
-  static ScriptStreamer* Create(
+  static ScriptStreamerImpl* Create(
       PendingScript* script,
       Type script_type,
       ScriptState* script_state,
       v8::ScriptCompiler::CompileOptions compile_options,
       RefPtr<WebTaskRunner> loading_task_runner) {
-    return new ScriptStreamer(script, script_type, script_state,
-                              compile_options, std::move(loading_task_runner));
+    return new ScriptStreamerImpl(script, script_type, script_state,
+                                  compile_options,
+                                  std::move(loading_task_runner));
   }
-  ScriptStreamer(PendingScript*,
-                 Type,
-                 ScriptState*,
-                 v8::ScriptCompiler::CompileOptions,
-                 RefPtr<WebTaskRunner>);
+  ScriptStreamerImpl(PendingScript*,
+                     Type,
+                     ScriptState*,
+                     v8::ScriptCompiler::CompileOptions,
+                     RefPtr<WebTaskRunner>);
 
   void StreamingComplete();
   void NotifyFinishedToClient();
 
+  bool IsFinished() const override;
+  bool StreamingSuppressed() const override { return streaming_suppressed_; }
+  void NotifyAppendData(ScriptResource*) override;
+  void NotifyFinished(Resource*) override;
+  void Cancel() override;
+
   static bool StartStreamingInternal(PendingScript*,
                                      Type,
                                      Settings*,
                                      ScriptState*,
                                      RefPtr<WebTaskRunner>);
 
   Member<PendingScript> pending_script_;
   // This pointer is weak. If PendingScript and its Resource are deleted
   // before ScriptStreamer, PendingScript will notify ScriptStreamer of its
   // deletion by calling cancel().
@@ skipping 30 matching lines @@
 
   // Encoding of the streamed script. Saved for sanity checking purposes.
   v8::ScriptCompiler::StreamedSource::Encoding encoding_;
 
   RefPtr<WebTaskRunner> loading_task_runner_;
 };
 
 }  // namespace blink
 
 #endif  // ScriptStreamer_h