runtime/FunctionConstructor.cpp

   1 /*
   2  *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
   3  *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 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 "FunctionPrototype.h"
  25 #include "JSFunction.h"
  26 #include "JSGlobalObject.h"
  27 #include "JSString.h"
  28 #include "Parser.h"
  29 #include "Debugger.h"
  30 #include "Lexer.h"
  31 #include "Nodes.h"
  32
  33 namespace JSC {
  34
  35 ASSERT_CLASS_FITS_IN_CELL(FunctionConstructor);
  36
  37 FunctionConstructor::FunctionConstructor(ExecState* exec, PassRefPtr<Structure> structure, FunctionPrototype* functionPrototype)
  38     : InternalFunction(&exec->globalData(), structure, Identifier(exec, functionPrototype->classInfo()->className))
  39 {
  40     putDirectWithoutTransition(exec->propertyNames().prototype, functionPrototype, DontEnum | DontDelete | ReadOnly);
  41
  42     // Number of arguments for constructor
  43     putDirectWithoutTransition(exec->propertyNames().length, jsNumber(exec, 1), ReadOnly | DontDelete | DontEnum);
  44 }
  45
  46 static JSObject* constructWithFunctionConstructor(ExecState* exec, JSObject*, const ArgList& args)
  47 {
  48     return constructFunction(exec, args);
  49 }
  50
  51 ConstructType FunctionConstructor::getConstructData(ConstructData& constructData)
  52 {
  53     constructData.native.function = constructWithFunctionConstructor;
  54     return ConstructTypeHost;
  55 }
  56
  57 static JSValuePtr callFunctionConstructor(ExecState* exec, JSObject*, JSValuePtr, const ArgList& args)
  58 {
  59     return constructFunction(exec, args);
  60 }
  61
  62 // ECMA 15.3.1 The Function Constructor Called as a Function
  63 CallType FunctionConstructor::getCallData(CallData& callData)
  64 {
  65     callData.native.function = callFunctionConstructor;
  66     return CallTypeHost;
  67 }
  68
  69 FunctionBodyNode* extractFunctionBody(ProgramNode* program)
  70 {
  71     if (!program)
  72         return 0;
  73
  74     StatementVector& children = program->children();
  75     if (children.size() != 1)
  76         return 0;
  77
  78     ExprStatementNode* exprStatement = static_cast<ExprStatementNode*>(children[0].get());
  79     ASSERT(exprStatement->isExprStatement());
  80     if (!exprStatement || !exprStatement->isExprStatement())
  81         return 0;
  82
  83     FuncExprNode* funcExpr = static_cast<FuncExprNode*>(exprStatement->expr());
  84     ASSERT(funcExpr->isFuncExprNode());
  85     if (!funcExpr || !funcExpr->isFuncExprNode())
  86         return 0;
  87
  88     FunctionBodyNode* body = funcExpr->body();
  89     ASSERT(body);
  90     return body;
  91 }
  92
  93 // ECMA 15.3.2 The Function Constructor
  94 JSObject* constructFunction(ExecState* exec, const ArgList& args, const Identifier& functionName, const UString& sourceURL, int lineNumber)
  95 {
  96     // Functions need to have a space following the opening { due to for web compatibility
  97     // see https://bugs.webkit.org/show_bug.cgi?id=24350
  98     // We also need \n before the closing } to handle // comments at the end of the last line
  99     UString program;
 100     if (args.isEmpty())
 101         program = "(function() { \n})";
 102     else if (args.size() == 1)
 103         program = "(function() { " + args.at(exec, 0).toString(exec) + "\n})";
 104     else {
 105         program = "(function(" + args.at(exec, 0).toString(exec);
 106         for (size_t i = 1; i < args.size() - 1; i++)
 107             program += "," + args.at(exec, i).toString(exec);
 108         program += ") { " + args.at(exec, args.size() - 1).toString(exec) + "\n})";
 109     }
 110
 111     int errLine;
 112     UString errMsg;
 113     SourceCode source = makeSource(program, sourceURL, lineNumber);
 114     RefPtr<ProgramNode> programNode = exec->globalData().parser->parse<ProgramNode>(exec, exec->dynamicGlobalObject()->debugger(), source, &errLine, &errMsg);
 115
 116     FunctionBodyNode* body = extractFunctionBody(programNode.get());
 117     if (!body)
 118         return throwError(exec, SyntaxError, errMsg, errLine, source.provider()->asID(), source.provider()->url());
 119
 120     JSGlobalObject* globalObject = exec->lexicalGlobalObject();
 121     ScopeChain scopeChain(globalObject, globalObject->globalData(), exec->globalThisValue());
 122     return new (exec) JSFunction(exec, functionName, body, scopeChain.node());
 123 }
 124
 125 // ECMA 15.3.2 The Function Constructor
 126 JSObject* constructFunction(ExecState* exec, const ArgList& args)
 127 {
 128     return constructFunction(exec, args, Identifier(exec, "anonymous"), UString(), 1);
 129 }
 130
 131 } // namespace JSC