runtime/JSNameScope.cpp

   1 /*
   2  * Copyright (C) 2008, 2009, 2012, 2015 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 #include "JSCatchScope.h"
  32 #include "JSFunctionNameScope.h"
  33
  34 namespace JSC {
  35
  36 const ClassInfo JSNameScope::s_info = { "NameScope", &Base::s_info, 0, CREATE_METHOD_TABLE(JSNameScope) };
  37
  38 JSNameScope* JSNameScope::create(VM& vm, JSGlobalObject* globalObject, JSScope* currentScope, SymbolTable* symbolTable, JSValue value, Type type)
  39 {
  40     switch (type) {
  41     case CatchScope:
  42         return JSCatchScope::create(vm, globalObject, currentScope, symbolTable, value);
  43     case FunctionNameScope:
  44         return JSFunctionNameScope::create(vm, globalObject, currentScope, symbolTable, value);
  45     }
  46     RELEASE_ASSERT_NOT_REACHED();
  47     return nullptr;
  48 }
  49
  50 JSValue JSNameScope::toThis(JSCell*, ExecState* exec, ECMAMode ecmaMode)
  51 {
  52     if (ecmaMode == StrictMode)
  53         return jsUndefined();
  54     return exec->globalThisValue();
  55 }
  56
  57 void JSNameScope::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
  58 {
  59     JSNameScope* thisObject = jsCast<JSNameScope*>(cell);
  60     if (slot.isStrictMode()) {
  61         // Double lookup in strict mode, but this only occurs when
  62         // a) indirectly writing to an exception slot
  63         // b) writing to a function expression name
  64         // (a) is unlikely, and (b) is an error.
  65         // Also with a single entry the symbol table lookup should simply be
  66         // a pointer compare.
  67         PropertySlot slot(thisObject);
  68         bool isWritable = true;
  69         symbolTableGet(thisObject, propertyName, slot, isWritable);
  70         if (!isWritable) {
  71             exec->vm().throwException(exec, createTypeError(exec, StrictModeReadonlyPropertyWriteError));
  72             return;
  73         }
  74     }
  75     if (symbolTablePut(thisObject, exec, propertyName, value, slot.isStrictMode()))
  76         return;
  77
  78     RELEASE_ASSERT_NOT_REACHED();
  79 }
  80
  81 bool JSNameScope::getOwnPropertySlot(JSObject* object, ExecState*, PropertyName propertyName, PropertySlot& slot)
  82 {
  83     return symbolTableGet(jsCast<JSNameScope*>(object), propertyName, slot);
  84 }
  85
  86 } // namespace JSC