runtime/FunctionConstructor.cpp

   1 /*
   2  *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
   3  *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2013 Apple Inc. All rights reserved.
   4  *
   5  *  This library is free software; you can redistribute it and/or
   6  *  modify it under the terms of the GNU Lesser General Public
   7  *  License as published by the Free Software Foundation; either
   8  *  version 2 of the License, or (at your option) any later version.
   9  *
  10  *  This library is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  *  Lesser General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU Lesser General Public
  16  *  License along with this library; if not, write to the Free Software
  17  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  18  *
  19  */
  20
  21 #include "config.h"
  22 #include "FunctionConstructor.h"
  23
  24 #include "Debugger.h"
  25 #include "ExceptionHelpers.h"
  26 #include "FunctionPrototype.h"
  27 #include "JSFunction.h"
  28 #include "JSGlobalObject.h"
  29 #include "JSString.h"
  30 #include "Lexer.h"
  31 #include "Nodes.h"
  32 #include "JSCInlines.h"
  33 #include "Parser.h"
  34 #include <wtf/text/StringBuilder.h>
  35
  36 namespace JSC {
  37
  38 STATIC_ASSERT_IS_TRIVIALLY_DESTRUCTIBLE(FunctionConstructor);
  39
  40 const ClassInfo FunctionConstructor::s_info = { "Function", &Base::s_info, 0, CREATE_METHOD_TABLE(FunctionConstructor) };
  41
  42 FunctionConstructor::FunctionConstructor(VM& vm, Structure* structure)
  43     : InternalFunction(vm, structure)
  44 {
  45 }
  46
  47 void FunctionConstructor::finishCreation(VM& vm, FunctionPrototype* functionPrototype)
  48 {
  49     Base::finishCreation(vm, functionPrototype->classInfo()->className);
  50     putDirectWithoutTransition(vm, vm.propertyNames->prototype, functionPrototype, DontEnum | DontDelete | ReadOnly);
  51
  52     // Number of arguments for constructor
  53     putDirectWithoutTransition(vm, vm.propertyNames->length, jsNumber(1), ReadOnly | DontDelete | DontEnum);
  54 }
  55
  56 static EncodedJSValue JSC_HOST_CALL constructWithFunctionConstructor(ExecState* exec)
  57 {
  58     ArgList args(exec);
  59     return JSValue::encode(constructFunction(exec, asInternalFunction(exec->callee())->globalObject(), args));
  60 }
  61
  62 ConstructType FunctionConstructor::getConstructData(JSCell*, ConstructData& constructData)
  63 {
  64     constructData.native.function = constructWithFunctionConstructor;
  65     return ConstructTypeHost;
  66 }
  67
  68 static EncodedJSValue JSC_HOST_CALL callFunctionConstructor(ExecState* exec)
  69 {
  70     ArgList args(exec);
  71     return JSValue::encode(constructFunction(exec, asInternalFunction(exec->callee())->globalObject(), args));
  72 }
  73
  74 // ECMA 15.3.1 The Function Constructor Called as a Function
  75 CallType FunctionConstructor::getCallData(JSCell*, CallData& callData)
  76 {
  77     callData.native.function = callFunctionConstructor;
  78     return CallTypeHost;
  79 }
  80
  81 // ECMA 15.3.2 The Function Constructor
  82 JSObject* constructFunction(ExecState* exec, JSGlobalObject* globalObject, const ArgList& args, const Identifier& functionName, const String& sourceURL, const TextPosition& position)
  83 {
  84     if (!globalObject->evalEnabled())
  85         return exec->vm().throwException(exec, createEvalError(exec, globalObject->evalDisabledErrorMessage()));
  86     return constructFunctionSkippingEvalEnabledCheck(exec, globalObject, args, functionName, sourceURL, position);
  87 }
  88
  89 JSObject* constructFunctionSkippingEvalEnabledCheck(
  90     ExecState* exec, JSGlobalObject* globalObject, const ArgList& args,
  91     const Identifier& functionName, const String& sourceURL,
  92     const TextPosition& position, int overrideLineNumber)
  93 {
  94     // How we stringify functions is sometimes important for web compatibility.
  95     // See https://bugs.webkit.org/show_bug.cgi?id=24350.
  96     String program;
  97     if (args.isEmpty())
  98         program = makeString("{function ", functionName.string(), "() {\n\n}}");
  99     else if (args.size() == 1)
 100         program = makeString("{function ", functionName.string(), "() {\n", args.at(0).toString(exec)->value(exec), "\n}}");
 101     else {
 102         StringBuilder builder;
 103         builder.appendLiteral("{function ");
 104         builder.append(functionName.string());
 105         builder.append('(');
 106         builder.append(args.at(0).toString(exec)->view(exec));
 107         for (size_t i = 1; i < args.size() - 1; i++) {
 108             builder.appendLiteral(", ");
 109             builder.append(args.at(i).toString(exec)->view(exec));
 110         }
 111         builder.appendLiteral(") {\n");
 112         builder.append(args.at(args.size() - 1).toString(exec)->view(exec));
 113         builder.appendLiteral("\n}}");
 114         program = builder.toString();
 115     }
 116
 117     SourceCode source = makeSource(program, sourceURL, position);
 118     JSObject* exception = nullptr;
 119     FunctionExecutable* function = FunctionExecutable::fromGlobalCode(functionName, *exec, source, exception, overrideLineNumber);
 120     if (!function) {
 121         ASSERT(exception);
 122         return exec->vm().throwException(exec, exception);
 123     }
 124
 125     return JSFunction::create(exec->vm(), function, globalObject);
 126 }
 127
 128 // ECMA 15.3.2 The Function Constructor
 129 JSObject* constructFunction(ExecState* exec, JSGlobalObject* globalObject, const ArgList& args)
 130 {
 131     return constructFunction(exec, globalObject, args, exec->propertyNames().anonymous, String(), TextPosition::minimumPosition());
 132 }
 133
 134 } // namespace JSC