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

/*
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 * modification, are permitted provided that the following conditions are
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 *
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef ScriptFunction_h
#define ScriptFunction_h

#include "bindings/core/v8/ScriptValue.h"
#include "core/CoreExport.h"
#include "platform/heap/Handle.h"
#include <v8.h>

namespace blink {

// A common way of using ScriptFunction is as follows:
//
// class DerivedFunction : public ScriptFunction {
//     // This returns a V8 function which the DerivedFunction is bound to.
//     // The DerivedFunction is destructed when the V8 function is
//     // garbage-collected.
//     static v8::Local<v8::Function> createFunction(ScriptState* scriptState)
//     {
//         DerivedFunction* self = new DerivedFunction(scriptState);
//         return self->bindToV8Function();
//     }
// };
class CORE_EXPORT ScriptFunction
    : public GarbageCollectedFinalized<ScriptFunction> {
 public:
  virtual ~ScriptFunction() {}
  DEFINE_INLINE_VIRTUAL_TRACE() {}

 protected:
  explicit ScriptFunction(ScriptState* scriptState)
      : m_scriptState(scriptState)
#if ENABLE(ASSERT)
        ,
        m_bindToV8FunctionAlreadyCalled(false)
#endif
  {
  }

  ScriptState* getScriptState() const { return m_scriptState.get(); }

  v8::Local<v8::Function> bindToV8Function();

 private:
  virtual ScriptValue call(ScriptValue) = 0;
  static void callCallback(const v8::FunctionCallbackInfo<v8::Value>&);

  RefPtr<ScriptState> m_scriptState;
#if ENABLE(ASSERT)
  // bindToV8Function must not be called twice.
  bool m_bindToV8FunctionAlreadyCalled;
#endif
};

}  // namespace blink

#endif