HTML MessagePort as mojo::MessagePipeHandle

third_party/WebKit/Source/platform/CrossThreadCopier.h

 /*
  * Copyright (C) 2009, 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 131 matching lines @@
 
 template <typename T, typename Deleter>
 struct CrossThreadCopier<std::unique_ptr<T, Deleter>> {
   STATIC_ONLY(CrossThreadCopier);
   using Type = std::unique_ptr<T, Deleter>;
   static std::unique_ptr<T, Deleter> copy(std::unique_ptr<T, Deleter> pointer) {
     return pointer;  // This is in fact a move.
   }
 };
 
+template <typename T, size_t inlineCapacity, typename Allocator>
+struct CrossThreadCopier<Vector<T, inlineCapacity, Allocator>> {
+  STATIC_ONLY(CrossThreadCopier);
+  using Type = Vector<T, inlineCapacity, Allocator>;
+  static Vector<T, inlineCapacity, Allocator> copy(
+      Vector<T, inlineCapacity, Allocator> pointer) {
+    return pointer;  // This is in fact a move.
+  }
+};

[kinuko, 2017/02/08 09:45:06]

Hmm, I think having CrossThreadCoppier for generic Vector is dangerous, if T
needs non-trivial copier support we need to recursively call
CrossThreadCopier::copy() on each element.  Also the comment doesn't look right
as this either moves or copies the given vector depending on what the caller
passes, as Vector supports both copy and move semantics.

Could we... maybe just define CrossThreadCopier for Vector<std::unique_ptr<T>>?

[darin (slow to review), 2017/02/08 17:09:18]

Great suggestion. That works perfectly.

+
 template <typename T>
 struct CrossThreadCopier<CrossThreadPersistent<T>>
     : public CrossThreadCopierPassThrough<CrossThreadPersistent<T>> {
   STATIC_ONLY(CrossThreadCopier);
 };
 
 template <typename T>
 struct CrossThreadCopier<CrossThreadWeakPersistent<T>>
     : public CrossThreadCopierPassThrough<CrossThreadWeakPersistent<T>> {
   STATIC_ONLY(CrossThreadCopier);
@@ skipping 54 matching lines @@
 struct CrossThreadCopier<ResourceResponse> {
   STATIC_ONLY(CrossThreadCopier);
   typedef WTF::PassedWrapper<std::unique_ptr<CrossThreadResourceResponseData>>
       Type;
   PLATFORM_EXPORT static Type copy(const ResourceResponse&);
 };
 
 }  // namespace blink
 
 #endif  // CrossThreadCopier_h