Begin implementing V8 bindings for Mojo

mojo/public/bindings/js/v8_conversions.h

Index: mojo/public/bindings/js/v8_conversions.h
diff --git a/mojo/public/bindings/js/v8_conversions.h b/mojo/public/bindings/js/v8_conversions.h
new file mode 100644
index 0000000000000000000000000000000000000000..232fdddc66dcbbc17e49d41bdf170dc4739d7962
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+++ b/mojo/public/bindings/js/v8_conversions.h
@@ -0,0 +1,45 @@
+// Copyright 2013 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 MOJO_PUBLIC_BINDINGS_JS_V8_CONVERSIONS_H_

[Aaron Boodman, 2013/11/09 08:26:02]

I don't understand why this isn't just another Wrapper type. Did you see the way
V8Converter<std::vector<T> > works in my old code?

It seems like that would be nice because the same code would work for arrays of
other types, like ints, or bools or whatever.

You will have to get rid of HasInstance(), but it seems like that could be
handled by making ToNative() return success/failure. Or you could rename it to
IsInstance() and define it for every Wrapper, not just "class" ones.

[abarth-chromium, 2013/11/09 08:52:37]

I'll take a closer look.
Yes.
That's a good idea.

+#define MOJO_PUBLIC_BINDINGS_JS_V8_CONVERSIONS_H_
+
+#include <vector>
+
+#include "v8/include/v8.h"
+
+namespace mojo {
+namespace js {
+
+template<typename T>
+bool ToNativeArray(v8::Handle<v8::Array> array, std::vector<T>* result) {
+  uint32_t length = array->Length();
+  result->reserve(length);
+  for (uint32_t i = 0; i < length; ++i) {
+    v8::Handle<v8::Value> value = array->Get(i);
+    if (!value->IsObject())
+      return false;
+    v8::Handle<v8::Object> object = v8::Handle<v8::Object>::Cast(value);
+    if (!Wrapper<T>::HasInstance(object))
+      return false;
+    result->push_back(Wrapper<T>::ToNative(object));
+  }
+  return true;
+}
+
+template<typename T>
+v8::Handle<v8::Array> ToObjectArray(v8::Isolate* isolate,
+                                    const std::vector<T>& native) {
+  uint32_t length = native.size();
+  v8::Handle<v8::Array> result = v8::Array::New(length);
+  for (uint32_t i = 0; i < length; ++i) {
+    result->Set(i, Wrapper<T>::ToObject(isolate, native[i]));
+  }
+  return result;
+}
+
+}  // js
+}  // mojo
+
+#endif  // MOJO_PUBLIC_BINDINGS_JS_V8_CONVERSIONS_H_