runtime/JSNameScope.cpp

   1 /*
   2  * Copyright (C) 2008, 2009, 2012 Apple Inc. All Rights Reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "JSNameScope.h"
  28
  29 #include "Error.h"
  30 #include "JSCInlines.h"
  31
  32 namespace JSC {
  33
  34 const ClassInfo JSNameScope::s_info = { "NameScope", &Base::s_info, 0, 0, CREATE_METHOD_TABLE(JSNameScope) };
  35
  36 void JSNameScope::visitChildren(JSCell* cell, SlotVisitor& visitor)
  37 {
  38     JSNameScope* thisObject = jsCast<JSNameScope*>(cell);
  39     ASSERT_GC_OBJECT_INHERITS(thisObject, info());
  40     COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
  41     ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
  42
  43     Base::visitChildren(thisObject, visitor);
  44     visitor.append(&thisObject->m_registerStore);
  45 }
  46
  47 JSValue JSNameScope::toThis(JSCell*, ExecState* exec, ECMAMode ecmaMode)
  48 {
  49     if (ecmaMode == StrictMode)
  50         return jsUndefined();
  51     return exec->globalThisValue();
  52 }
  53
  54 void JSNameScope::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
  55 {
  56     JSNameScope* thisObject = jsCast<JSNameScope*>(cell);
  57     if (slot.isStrictMode()) {
  58         // Double lookup in strict mode, but this only occurs when
  59         // a) indirectly writing to an exception slot
  60         // b) writing to a function expression name
  61         // (a) is unlikely, and (b) is an error.
  62         // Also with a single entry the symbol table lookup should simply be
  63         // a pointer compare.
  64         PropertySlot slot(thisObject);
  65         bool isWritable = true;
  66         symbolTableGet(thisObject, propertyName, slot, isWritable);
  67         if (!isWritable) {
  68             exec->vm().throwException(exec, createTypeError(exec, StrictModeReadonlyPropertyWriteError));
  69             return;
  70         }
  71     }
  72     if (symbolTablePut(thisObject, exec, propertyName, value, slot.isStrictMode()))
  73         return;
  74
  75     RELEASE_ASSERT_NOT_REACHED();
  76 }
  77
  78 bool JSNameScope::getOwnPropertySlot(JSObject* object, ExecState*, PropertyName propertyName, PropertySlot& slot)
  79 {
  80     return symbolTableGet(jsCast<JSNameScope*>(object), propertyName, slot);
  81 }
  82
  83 } // namespace JSC