public void Visit(ConstantWrapper node)
{
if (node != null)
{
// allow string, number, true, false, and null.
switch (node.PrimitiveType)
{
case PrimitiveType.Boolean:
m_writer.Write((bool)node.Value ? "true" : "false");
break;
case PrimitiveType.Null:
m_writer.Write("null");
break;
case PrimitiveType.Number:
OutputNumber((double)node.Value, node.Context);
break;
case PrimitiveType.String:
case PrimitiveType.Other:
// string -- or treat it like a string
OutputString(node.Value.ToString());
break;
}
}
}
public override void CleanupNodes()
{
base.CleanupNodes();
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// if the if-condition is a constant, we can eliminate one of the two branches
ConstantWrapper constantCondition = Condition as ConstantWrapper;
if (constantCondition != null)
{
// instead, replace the condition with a 1 if it's always true or a 0 if it's always false
if (constantCondition.IsNotOneOrPositiveZero)
{
try
{
Condition = new ConstantWrapper(constantCondition.ToBoolean() ? 1 : 0, PrimitiveType.Number, null, Parser);
}
catch (InvalidCastException)
{
// ignore any invalid cast exceptions
}
}
}
}
}
public override void CleanupNodes()
{
base.CleanupNodes();
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// if the condition is a literal, evaluating the condition doesn't do anything, AND
// we know now whether it's true or not.
ConstantWrapper literalCondition = m_condition as ConstantWrapper;
if (literalCondition != null)
{
try
{
// if the boolean represenation of the literal is true, we can replace the condition operator
// with the true expression; otherwise we can replace it with the false expression
Parent.ReplaceChild(this, literalCondition.ToBoolean() ? m_trueExpression : m_falseExpression);
}
catch (InvalidCastException)
{
// ignore any invalid cast errors
}
}
}
}
public override void CleanupNodes()
{
base.CleanupNodes();
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
ConstantWrapper constantCondition = Condition as ConstantWrapper;
if (constantCondition != null)
{
try
{
// if condition is always false, change it to a zero (only one byte)
// and if it is always true, remove it (default behavior)
if (constantCondition.ToBoolean())
{
// always true -- don't need a condition at all
Condition = null;
}
else if (constantCondition.IsNotOneOrPositiveZero)
{
// always false and it's not already a zero. Make it so (only one byte)
Condition = new ConstantWrapper(0, PrimitiveType.Number, null, Parser);
}
}
catch (InvalidCastException)
{
// ignore any invalid cast exceptions
}
}
}
}
public void Visit(ConstantWrapper node)
{
if (node != null)
{
DoesRequire = true;
}
}
public void Visit(ConstantWrapper node)
{
// elisions in rrays are allowed, but don't recurse or contribute.
// nothing else is allowed, though.
if (node != null && node.Value != Missing.Value)
{
ReportError(node);
}
}
public override void Visit(CallNode node)
{
base.Visit(node);
if (ShouldInsertModulePathArgument(node))
{
var modulePathNode = new ConstantWrapper(modulePath, PrimitiveType.String, node.Context, node.Parser);
node.Arguments.Insert(0, modulePathNode);
}
}
private bool IsMinificationHint(ConstantWrapper node)
{
var isHint = false;
if (node.PrimitiveType == PrimitiveType.String)
{
// try splitting on commas and removing empty items
var sections = node.ToString().Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
foreach (var section in sections)
{
// valid hints are:
// name:nomunge don't automatically rename the field defined in this scope named "name"
// if name is missing (colon is the first character) or "*", then don't rename ANY
// fields defined in the current scope.
var ndxColon = section.IndexOf(':');
if (ndxColon >= 0)
{
// make sure this is a "nomunge" hint. If it is, then the entire node is treated as a hint and
// will be removed from the AST.
if (string.Compare(section.Substring(ndxColon + 1).Trim(), "nomunge", StringComparison.OrdinalIgnoreCase) == 0)
{
// it is.
isHint = true;
// get the name that we don't want to munge. Null means all. Convert "*"
// to null.
var identifier = section.Substring(0, ndxColon).Trim();
if (string.IsNullOrEmpty(identifier) || string.CompareOrdinal(identifier, "*") == 0)
{
identifier = null;
}
// get the current scope and iterate over all the fields within it
// looking for just the ones that are defined here (outer is null)
var currentScope = node.EnclosingScope ?? m_globalScope;
foreach (var field in currentScope.NameTable.Values)
{
if (field.OuterField == null)
{
// if the identifier is null or matches exactly, mark it as not crunchable
if (identifier == null || string.CompareOrdinal(identifier, field.Name) == 0)
{
field.CanCrunch = false;
}
}
}
}
}
}
}
return(isHint);
}
public bool IsSingleConstantArgument(string argumentValue)
{
if (m_list.Count == 1)
{
ConstantWrapper constantWrapper = m_list[0] as ConstantWrapper;
if (constantWrapper != null &&
string.CompareOrdinal(constantWrapper.Value.ToString(), argumentValue) == 0)
{
return(true);
}
}
return(false);
}
public LiteralReference(ConstantWrapper constantWrapper, ActivationObject childScope, List <ConstantWrapper> sharedList)
{
m_count = 1;
m_childScope = childScope;
// use the shared list passed to us, or create a new one
m_constantWrappers = sharedList ?? new List <ConstantWrapper>();
// only add the constant wrapper passed to us IF it isn't ALREADY in the list
// (will only happen with a shared list)
if (!m_constantWrappers.Contains(constantWrapper))
{
m_constantWrappers.Add(constantWrapper);
}
}
internal override void AnalyzeNode()
{
// recurse first, then check to see if the unary is still needed
base.AnalyzeNode();
// if the operand is a numeric literal
ConstantWrapper constantWrapper = Operand as ConstantWrapper;
if (constantWrapper != null &&
constantWrapper.IsNumericLiteral)
{
// get the value of the constant. We've already screened it for numeric, so
// we don't have to worry about catching any errors
double doubleValue = constantWrapper.ToNumber();
// if this is a unary minus...
if (OperatorToken == JSToken.Minus &&
Parser.Settings.IsModificationAllowed(TreeModifications.ApplyUnaryMinusToNumericLiteral))
{
// negate the value
constantWrapper.Value = -doubleValue;
// replace us with the negated constant
if (Parent.ReplaceChild(this, constantWrapper))
{
// the context for the minus will include the number (its operand),
// but the constant will just be the number. Update the context on
// the constant to be a copy of the context on the operator
constantWrapper.Context = Context.Clone();
return;
}
}
else if (OperatorToken == JSToken.Plus &&
Parser.Settings.IsModificationAllowed(TreeModifications.RemoveUnaryPlusOnNumericLiteral))
{
// +NEG is still negative, +POS is still positive, and +0 is still 0.
// so just get rid of the unary operator altogether
if (Parent.ReplaceChild(this, constantWrapper))
{
// the context for the unary will include the number (its operand),
// but the constant will just be the number. Update the context on
// the constant to be a copy of the context on the operator
constantWrapper.Context = Context.Clone();
return;
}
}
}
}
public override void Visit(ConstantWrapper node)
{
if (node != null)
{
// no children, so don't bother calling the base.
if (node.PrimitiveType == PrimitiveType.Boolean
&& m_parser.Settings.IsModificationAllowed(TreeModifications.BooleanLiteralsToNotOperators))
{
node.Parent.ReplaceChild(node, new NumericUnary(
node.Context,
m_parser,
new ConstantWrapper(node.ToBoolean() ? 0 : 1, PrimitiveType.Number, node.Context, m_parser),
JSToken.LogicalNot));
}
}
}
internal override string GetFunctionGuess(AstNode target)
{
// MSN VOODOO: treat the as and ns methods as special if the expression is the root,
// the parent is the call, and there is one string parameter -- use the string parameter
if (Root == target && (Name == "as" || Name == "ns"))
{
CallNode call = Parent as CallNode;
if (call != null && call.Arguments.Count == 1)
{
ConstantWrapper firstParam = call.Arguments[0] as ConstantWrapper;
if (firstParam != null)
{
return(firstParam.ToString());
}
}
}
return(Name);
}
public override void Visit(ConstantWrapper node)
{
// by default this node has nothing to do and no children to recurse.
// but if this node's parent is a block, then this is an expression statement
// consisting of a single string literal. Normally we would ignore these -- if
// they occured at the top of the block they would be DirectivePrologues. So because
// this exists, it must not be at the top. But we still want to check it for the nomunge
// hints and respect them if that's what it is.
if (node != null && node.Parent is Block)
{
// if this is a hint, process it as such.
if (IsMinificationHint(node))
{
// and then remove it. We can do that here, because blocks are processed
// in reverse order.
node.Parent.ReplaceChild(node, null);
}
}
}
/// <summary>
/// Optimized string literal concatenation for repeat usage pattern, avoiding multiple copying and allocation
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public StringList Concat(ConstantWrapper other)
{
var left = this.Value;
if (this.PrimitiveType != PrimitiveType.String)
{
left = this.ToString();
}
object right = null;
if (other != null)
{
right = other.Value;
if (other.PrimitiveType != PrimitiveType.String)
{
right = other.ToString();
}
}
return(new StringList(left, right));
}
internal override string GetFunctionGuess(AstNode target)
{
// get our guess from the function call
string funcName = m_func.GetFunctionGuess(target);
// MSN VOODOO: if this is the addMethod method, then the
// name of the function is the first parameter.
// The syntax of the add method call is: obj.addMethod("name",function(){...})
// so there should be two parameters....
if (funcName == "addMethod" && m_args.Count == 2)
{
// the first one should be a string constant....
ConstantWrapper firstParam = m_args[0] as ConstantWrapper;
// and the second one should be the function expression we're looking for
if ((firstParam != null) && (firstParam.Value is string) && (m_args[1] == target))
{
// use that first parameter as the guess
funcName = firstParam.ToString();
}
}
return(funcName);
}
public override void CleanupNodes()
{
base.CleanupNodes();
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// if the condition is a constant, we can simplify things
ConstantWrapper constantCondition = Condition as ConstantWrapper;
if (constantCondition != null && constantCondition.IsNotOneOrPositiveZero)
{
try
{
// the condition is a constant, so it is always either true or false
// we can replace the condition with a one or a zero -- only one byte
Condition = new ConstantWrapper(constantCondition.ToBoolean() ? 1 : 0, PrimitiveType.Number, null, Parser);
}
catch (InvalidCastException)
{
// ignore any invalid cast errors
}
}
}
}
/// <summary>
/// Evaluate: (CONST [op] OTHER) [op] CONST
/// </summary>
/// <param name="thisConstant">second constant</param>
/// <param name="otherConstant">first constant</param>
/// <param name="leftOperator">first operator</param>
private void EvalFarToTheLeft(BinaryOperator node, ConstantWrapper thisConstant, ConstantWrapper otherConstant, BinaryOperator leftOperator)
{
if (leftOperator.OperatorToken == JSToken.Minus)
{
if (node.OperatorToken == JSToken.Plus)
{
// minus-plus
ConstantWrapper newLiteral = NumericAddition(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
RotateFromRight(node, leftOperator, newLiteral);
}
}
else if (node.OperatorToken == JSToken.Minus)
{
// minus-minus
ConstantWrapper newLiteral = Minus(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
RotateFromRight(node, leftOperator, newLiteral);
}
}
}
else if (node.OperatorToken == JSToken.Multiply)
{
if (leftOperator.OperatorToken == JSToken.Multiply || leftOperator.OperatorToken == JSToken.Divide)
{
ConstantWrapper newLiteral = Multiply(otherConstant, thisConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, newLiteral))
{
RotateFromRight(node, leftOperator, newLiteral);
}
}
}
else if (node.OperatorToken == JSToken.Divide)
{
if (leftOperator.OperatorToken == JSToken.Divide)
{
// divide-divide
ConstantWrapper newLiteral = Divide(otherConstant, thisConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, newLiteral)
&& newLiteral.ToCode().Length <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
RotateFromRight(node, leftOperator, newLiteral);
}
}
else if (leftOperator.OperatorToken == JSToken.Multiply)
{
// mult-divide
ConstantWrapper otherOverThis = Divide(otherConstant, thisConstant);
ConstantWrapper thisOverOther = Divide(thisConstant, otherConstant);
int otherOverThisLength = otherOverThis != null ? otherOverThis.ToCode().Length : int.MaxValue;
int thisOverOtherLength = thisOverOther != null ? thisOverOther.ToCode().Length : int.MaxValue;
if (otherOverThis != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, otherOverThis)
&& (thisOverOther == null || otherOverThisLength < thisOverOtherLength))
{
if (otherOverThisLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
RotateFromRight(node, leftOperator, otherOverThis);
}
}
else if (thisOverOther != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, thisOverOther))
{
if (thisOverOtherLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// swap the operands
leftOperator.SwapOperands();
// operator is the opposite
leftOperator.OperatorToken = JSToken.Divide;
RotateFromLeft(node, leftOperator, thisOverOther);
}
}
}
}
}
internal override void AnalyzeNode()
{
// if we don't even have any resource strings, then there's nothing
// we need to do and we can just perform the base operation
ResourceStrings resourceStrings = Parser.ResourceStrings;
if (resourceStrings != null && resourceStrings.Count > 0)
{
// see if the root object is a lookup that corresponds to the
// global value (not a local field) for our resource object
// (same name)
Lookup rootLookup = Root as Lookup;
if (rootLookup != null &&
rootLookup.LocalField == null &&
string.CompareOrdinal(rootLookup.Name, resourceStrings.Name) == 0)
{
// it is -- we're going to replace this with a string value.
// if this member name is a string on the object, we'll replacve it with
// the literal. Otherwise we'll replace it with an empty string.
// see if the string resource contains this value
ConstantWrapper stringLiteral = new ConstantWrapper(
resourceStrings[Name],
PrimitiveType.String,
Context,
Parser
);
Parent.ReplaceChild(this, stringLiteral);
// analyze the literal
stringLiteral.AnalyzeNode();
return;
}
}
// if we are replacing property names and we have something to replace
if (Parser.Settings.HasRenamePairs && Parser.Settings.ManualRenamesProperties &&
Parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming))
{
// see if this name is a target for replacement
string newName = Parser.Settings.GetNewName(Name);
if (!string.IsNullOrEmpty(newName))
{
// it is -- set the name to the new name
Name = newName;
}
}
// recurse
base.AnalyzeNode();
/* REVIEW: might be too late in the parsing -- references to the variable may have
* already been analyzed and found undefined
* // see if we are assigning to a member on the global window object
* BinaryOperator binaryOp = Parent as BinaryOperator;
* if (binaryOp != null && binaryOp.IsAssign && m_rootObject.IsWindowLookup)
* {
* // make sure the name of this property is a valid global variable, since we
* // are now assigning to it.
* if (Parser.GlobalScope[Name] == null)
* {
* // it's not -- we need to add it to our list of known globals
* // by defining a global field for it
* Parser.GlobalScope.DeclareField(Name, null, 0);
* }
* }
*/
}
//---------------------------------------------------------------------------------------
// ParseLeftHandSideExpression
//
// LeftHandSideExpression :
// PrimaryExpression Accessor |
// 'new' LeftHandSideExpression |
// FunctionExpression
//
// PrimaryExpression :
// 'this' |
// Identifier |
// Literal |
// '(' Expression ')'
//
// FunctionExpression :
// 'function' OptionalFuncName '(' FormalParameterList ')' { FunctionBody }
//
// OptionalFuncName :
// <empty> |
// Identifier
//---------------------------------------------------------------------------------------
private AstNode ParseLeftHandSideExpression(bool isMinus)
{
AstNode ast = null;
bool isFunction = false;
List<Context> newContexts = null;
TryItAgain:
// new expression
while (JSToken.New == m_currentToken.Token)
{
if (null == newContexts)
newContexts = new List<Context>(4);
newContexts.Add(m_currentToken.Clone());
GetNextToken();
}
JSToken token = m_currentToken.Token;
switch (token)
{
// primary expression
case JSToken.Identifier:
ast = new Lookup(m_scanner.GetIdentifier(), m_currentToken.Clone(), this);
break;
case JSToken.ConditionalCommentStart:
// skip past the start to the next token
GetNextToken();
if (m_currentToken.Token == JSToken.PreprocessorConstant)
{
// we have /*@id
ast = new ConstantWrapperPP(m_currentToken.Code, true, m_currentToken.Clone(), this);
GetNextToken();
if (m_currentToken.Token == JSToken.ConditionalCommentEnd)
{
// skip past the closing comment
GetNextToken();
}
else
{
// we ONLY support /*@id@*/ in expressions right now. If there's not
// a closing comment after the ID, then we don't support it.
// throw an error, skip to the end of the comment, then ignore it and start
// looking for the next token.
m_currentToken.HandleError(JSError.ConditionalCompilationTooComplex);
// skip to end of conditional comment
while (m_currentToken.Token != JSToken.EndOfFile && m_currentToken.Token != JSToken.ConditionalCommentEnd)
{
GetNextToken();
}
GetNextToken();
goto TryItAgain;
}
}
else if (m_currentToken.Token == JSToken.ConditionalCommentEnd)
{
// empty conditional comment! Ignore.
GetNextToken();
goto TryItAgain;
}
else
{
// we DON'T have "/*@IDENT". We only support "/*@IDENT @*/", so since this isn't
// and id, throw the error, skip to the end of the comment, and ignore it
// by looping back and looking for the NEXT token.
m_currentToken.HandleError(JSError.ConditionalCompilationTooComplex);
// skip to end of conditional comment
while (m_currentToken.Token != JSToken.EndOfFile && m_currentToken.Token != JSToken.ConditionalCommentEnd)
{
GetNextToken();
}
GetNextToken();
goto TryItAgain;
}
break;
case JSToken.This:
ast = new ThisLiteral(m_currentToken.Clone(), this);
break;
case JSToken.StringLiteral:
ast = new ConstantWrapper(m_scanner.StringLiteral, PrimitiveType.String, m_currentToken.Clone(), this);
break;
case JSToken.IntegerLiteral:
case JSToken.NumericLiteral:
{
Context numericContext = m_currentToken.Clone();
double doubleValue;
if (ConvertNumericLiteralToDouble(m_currentToken.Code, (token == JSToken.IntegerLiteral), out doubleValue))
{
// conversion worked fine
// check for some boundary conditions
if (doubleValue == double.MaxValue)
{
ReportError(JSError.NumericMaximum, numericContext, true);
}
else if (isMinus && -doubleValue == double.MinValue)
{
ReportError(JSError.NumericMinimum, numericContext, true);
}
// create the constant wrapper from the value
ast = new ConstantWrapper(doubleValue, PrimitiveType.Number, numericContext, this);
}
else
{
// check to see if we went overflow
if (double.IsInfinity(doubleValue))
{
ReportError(JSError.NumericOverflow, numericContext, true);
}
// regardless, we're going to create a special constant wrapper
// that simply echos the input as-is
ast = new ConstantWrapper(m_currentToken.Code, PrimitiveType.Other, numericContext, this);
}
break;
}
case JSToken.True:
ast = new ConstantWrapper(true, PrimitiveType.Boolean, m_currentToken.Clone(), this);
break;
case JSToken.False:
ast = new ConstantWrapper(false, PrimitiveType.Boolean, m_currentToken.Clone(), this);
break;
case JSToken.Null:
ast = new ConstantWrapper(null, PrimitiveType.Null, m_currentToken.Clone(), this);
break;
case JSToken.PreprocessorConstant:
ast = new ConstantWrapperPP(m_currentToken.Code, false, m_currentToken.Clone(), this);
break;
case JSToken.DivideAssign:
// normally this token is not allowed on the left-hand side of an expression.
// BUT, this might be the start of a regular expression that begins with an equals sign!
// we need to test to see if we can parse a regular expression, and if not, THEN
// we can fail the parse.
case JSToken.Divide:
// could it be a regexp?
String source = m_scanner.ScanRegExp();
if (source != null)
{
// parse the flags (if any)
String flags = m_scanner.ScanRegExpFlags();
// create the literal
ast = new RegExpLiteral(source, flags, m_currentToken.Clone(), this);
break;
}
goto default;
// expression
case JSToken.LeftParenthesis:
{
// save the current context reference
Context openParenContext = m_currentToken.Clone();
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_ParenExpressionNoSkipToken);
try
{
// parse an expression
ast = ParseExpression();
// update the expression's context with the context of the open paren
ast.Context.UpdateWith(openParenContext);
if (JSToken.RightParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoRightParenthesis);
}
else
{
// add the closing paren to the expression context
ast.Context.UpdateWith(m_currentToken);
}
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_ParenExpressionNoSkipToken, exc) == -1)
throw;
else
ast = exc._partiallyComputedNode;
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_ParenExpressionNoSkipToken);
}
if (ast == null) //this can only happen when catching the exception and nothing was sent up by the caller
SkipTokensAndThrow();
}
break;
// array initializer
case JSToken.LeftBracket:
Context listCtx = m_currentToken.Clone();
AstNodeList list = new AstNodeList(m_currentToken.Clone(), this);
GetNextToken();
while (JSToken.RightBracket != m_currentToken.Token)
{
if (JSToken.Comma != m_currentToken.Token)
{
m_noSkipTokenSet.Add(NoSkipTokenSet.s_ArrayInitNoSkipTokenSet);
try
{
list.Append(ParseExpression(true));
if (JSToken.Comma != m_currentToken.Token)
{
if (JSToken.RightBracket != m_currentToken.Token)
ReportError(JSError.NoRightBracket);
break;
}
else
{
// we have a comma -- skip it
GetNextToken();
// if the next token is the closing brackets, then we need to
// add a missing value to the array because we end in a comma and
// we need to keep it for cross-platform compat.
// TECHNICALLY, that puts an extra item into the array for most modern browsers, but not ALL.
if (m_currentToken.Token == JSToken.RightBracket)
{
list.Append(new ConstantWrapper(Missing.Value, PrimitiveType.Other, m_currentToken.Clone(), this));
}
}
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode != null)
list.Append(exc._partiallyComputedNode);
if (IndexOfToken(NoSkipTokenSet.s_ArrayInitNoSkipTokenSet, exc) == -1)
{
listCtx.UpdateWith(CurrentPositionContext());
exc._partiallyComputedNode = new ArrayLiteral(listCtx, this, list);
throw;
}
else
{
if (JSToken.RightBracket == m_currentToken.Token)
break;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_ArrayInitNoSkipTokenSet);
}
}
else
{
// comma -- missing array item in the list
list.Append(new ConstantWrapper(Missing.Value, PrimitiveType.Other, m_currentToken.Clone(), this));
// skip over the comma
GetNextToken();
// if the next token is the closing brace, then we end with a comma -- and we need to
// add ANOTHER missing value to make sure this last comma doesn't get left off.
// TECHNICALLY, that puts an extra item into the array for most modern browsers, but not ALL.
if (m_currentToken.Token == JSToken.RightBracket)
{
list.Append(new ConstantWrapper(Missing.Value, PrimitiveType.Other, m_currentToken.Clone(), this));
}
}
}
listCtx.UpdateWith(m_currentToken);
ast = new ArrayLiteral(listCtx, this, list);
break;
// object initializer
case JSToken.LeftCurly:
Context objCtx = m_currentToken.Clone();
GetNextToken();
// we're going to keep the keys and values in separate lists, but make sure
// that the indexes correlate (keyList[n] is associated with valueList[n])
List<ObjectLiteralField> keyList = new List<ObjectLiteralField>();
List<AstNode> valueList = new List<AstNode>();
if (JSToken.RightCurly != m_currentToken.Token)
{
for (; ; )
{
ObjectLiteralField field = null;
AstNode value = null;
bool getterSetter = false;
string ident;
switch (m_currentToken.Token)
{
case JSToken.Identifier:
field = new ObjectLiteralField(m_scanner.GetIdentifier(), PrimitiveType.String, m_currentToken.Clone(), this);
break;
case JSToken.StringLiteral:
field = new ObjectLiteralField(m_scanner.StringLiteral, PrimitiveType.String, m_currentToken.Clone(), this);
break;
case JSToken.IntegerLiteral:
case JSToken.NumericLiteral:
{
double doubleValue;
if (ConvertNumericLiteralToDouble(m_currentToken.Code, (m_currentToken.Token == JSToken.IntegerLiteral), out doubleValue))
{
// conversion worked fine
field = new ObjectLiteralField(
doubleValue,
PrimitiveType.Number,
m_currentToken.Clone(),
this
);
}
else
{
// something went wrong and we're not sure the string representation in the source is
// going to convert to a numeric value well
if (double.IsInfinity(doubleValue))
{
ReportError(JSError.NumericOverflow, m_currentToken.Clone(), true);
}
// use the source as the field name, not the numeric value
field = new ObjectLiteralField(
m_currentToken.Code,
PrimitiveType.Other,
m_currentToken.Clone(),
this);
}
break;
}
case JSToken.Get:
case JSToken.Set:
if (m_scanner.PeekToken() == JSToken.Colon)
{
// the field is either "get" or "set" and isn't the special Mozilla getter/setter
field = new ObjectLiteralField(m_currentToken.Code, PrimitiveType.String, m_currentToken.Clone(), this);
}
else
{
// ecma-script get/set property construct
getterSetter = true;
bool isGet = (m_currentToken.Token == JSToken.Get);
value = ParseFunction(
(JSToken.Get == m_currentToken.Token ? FunctionType.Getter : FunctionType.Setter),
m_currentToken.Clone()
);
FunctionObject funcExpr = value as FunctionObject;
if (funcExpr != null)
{
// getter/setter is just the literal name with a get/set flag
field = new GetterSetter(
funcExpr.Name,
isGet,
funcExpr.IdContext.Clone(),
this
);
}
else
{
ReportError(JSError.FunctionExpressionExpected);
}
}
break;
default:
// NOT: identifier, string, number, or getter/setter.
// see if it's a token that COULD be an identifier.
ident = JSKeyword.CanBeIdentifier(m_currentToken.Token);
if (ident != null)
{
// don't throw a warning -- it's okay to have a keyword that
// can be an identifier here.
field = new ObjectLiteralField(ident, PrimitiveType.String, m_currentToken.Clone(), this);
}
else
{
ReportError(JSError.NoMemberIdentifier);
field = new ObjectLiteralField("_#Missing_Field#_" + s_cDummyName++, PrimitiveType.String, CurrentPositionContext(), this);
}
break;
}
if (field != null)
{
if (!getterSetter)
{
GetNextToken();
}
m_noSkipTokenSet.Add(NoSkipTokenSet.s_ObjectInitNoSkipTokenSet);
try
{
if (!getterSetter)
{
// get the value
if (JSToken.Colon != m_currentToken.Token)
{
ReportError(JSError.NoColon, true);
value = ParseExpression(true);
}
else
{
GetNextToken();
value = ParseExpression(true);
}
}
// put the pair into the list of fields
keyList.Add(field);
valueList.Add(value);
if (JSToken.RightCurly == m_currentToken.Token)
break;
else
{
if (JSToken.Comma == m_currentToken.Token)
{
// skip the comma
GetNextToken();
// if the next token is the right-curly brace, then we ended
// the list with a comma, which is perfectly fine
if (m_currentToken.Token == JSToken.RightCurly)
{
break;
}
}
else
{
if (m_scanner.GotEndOfLine)
{
ReportError(JSError.NoRightCurly);
}
else
ReportError(JSError.NoComma, true);
SkipTokensAndThrow();
}
}
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode != null)
{
// the problem was in ParseExpression trying to determine value
value = exc._partiallyComputedNode;
keyList.Add(field);
valueList.Add(value);
}
if (IndexOfToken(NoSkipTokenSet.s_ObjectInitNoSkipTokenSet, exc) == -1)
{
exc._partiallyComputedNode = new ObjectLiteral(objCtx, this, keyList.ToArray(), valueList.ToArray());
throw;
}
else
{
if (JSToken.Comma == m_currentToken.Token)
GetNextToken();
if (JSToken.RightCurly == m_currentToken.Token)
break;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_ObjectInitNoSkipTokenSet);
}
}
}
}
objCtx.UpdateWith(m_currentToken);
ast = new ObjectLiteral(objCtx, this, keyList.ToArray(), valueList.ToArray());
break;
// function expression
case JSToken.Function:
ast = ParseFunction(FunctionType.Expression, m_currentToken.Clone());
isFunction = true;
break;
case JSToken.AspNetBlock:
ast = ParseAspNetBlock(consumeSemicolonIfPossible: false);
break;
default:
string identifier = JSKeyword.CanBeIdentifier(m_currentToken.Token);
if (null != identifier)
{
ast = new Lookup(identifier, m_currentToken.Clone(), this);
}
else
{
ReportError(JSError.ExpressionExpected);
SkipTokensAndThrow();
}
break;
}
// can be a CallExpression, that is, followed by '.' or '(' or '['
if (!isFunction)
GetNextToken();
return MemberExpression(ast, newContexts);
}
//---------------------------------------------------------------------------------------
// ParseWithStatement
//
// WithStatement :
// 'with' '(' Expression ')' Statement
//---------------------------------------------------------------------------------------
private WithNode ParseWithStatement()
{
Context withCtx = m_currentToken.Clone();
AstNode obj = null;
Block block = null;
m_blockType.Add(BlockType.Block);
try
{
GetNextToken();
if (JSToken.LeftParenthesis != m_currentToken.Token)
ReportError(JSError.NoLeftParenthesis);
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
obj = ParseExpression();
if (JSToken.RightParenthesis != m_currentToken.Token)
{
withCtx.UpdateWith(obj.Context);
ReportError(JSError.NoRightParenthesis);
}
else
withCtx.UpdateWith(m_currentToken);
GetNextToken();
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
// give up
exc._partiallyComputedNode = null;
throw;
}
else
{
if (exc._partiallyComputedNode == null)
obj = new ConstantWrapper(true, PrimitiveType.Boolean, CurrentPositionContext(), this);
else
obj = exc._partiallyComputedNode;
withCtx.UpdateWith(obj.Context);
if (exc._token == JSToken.RightParenthesis)
GetNextToken();
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, withCtx, true);
}
WithScope withScope = new WithScope(ScopeStack.Peek(), withCtx, this);
ScopeStack.Push(withScope);
try
{
// parse a Statement, not a SourceElement
AstNode statement = ParseStatement(false);
// but make sure we save it as a block
block = statement as Block;
if (block == null)
{
block = new Block(statement.Context, this);
block.Append(statement);
}
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode == null)
{
block = new Block(CurrentPositionContext(), this);
}
else
{
block = exc._partiallyComputedNode as Block;
if (block == null)
{
block = new Block(exc._partiallyComputedNode.Context, this);
block.Append(exc._partiallyComputedNode);
}
}
block.BlockScope = withScope;
exc._partiallyComputedNode = new WithNode(withCtx, this, obj, block);
throw;
}
finally
{
// pop off the with-scope
ScopeStack.Pop();
// save the with-scope on the block
block.BlockScope = withScope;
}
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return new WithNode(withCtx, this, obj, block);
}
//---------------------------------------------------------------------------------------
// ParseDoStatement
//
// DoStatement:
// 'do' Statement 'while' '(' Expression ')'
//---------------------------------------------------------------------------------------
private DoWhile ParseDoStatement()
{
Context doCtx = null;
AstNode body = null;
AstNode condition = null;
m_blockType.Add(BlockType.Loop);
try
{
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_DoWhileBodyNoSkipTokenSet);
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, m_currentToken.Clone(), true);
}
try
{
// parse a Statement, not a SourceElement
body = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
// make up a block for the do while
if (exc._partiallyComputedNode != null)
body = exc._partiallyComputedNode;
else
body = new Block(CurrentPositionContext(), this);
if (IndexOfToken(NoSkipTokenSet.s_DoWhileBodyNoSkipTokenSet, exc) == -1)
{
// we have to pass the exception to someone else, make as much as you can from the 'do while'
exc._partiallyComputedNode = new DoWhile(CurrentPositionContext(), this,
body,
new ConstantWrapper(false, PrimitiveType.Boolean, CurrentPositionContext(), this));
throw;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_DoWhileBodyNoSkipTokenSet);
}
if (JSToken.While != m_currentToken.Token)
{
ReportError(JSError.NoWhile);
}
doCtx = m_currentToken.Clone();
GetNextToken();
if (JSToken.LeftParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoLeftParenthesis);
}
GetNextToken();
// catch here so the body of the do_while is not thrown away
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
condition = ParseExpression();
if (JSToken.RightParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoRightParenthesis);
doCtx.UpdateWith(condition.Context);
}
else
doCtx.UpdateWith(m_currentToken);
GetNextToken();
}
catch (RecoveryTokenException exc)
{
// make up a condition
if (exc._partiallyComputedNode != null)
condition = exc._partiallyComputedNode;
else
condition = new ConstantWrapper(false, PrimitiveType.Boolean, CurrentPositionContext(), this);
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
exc._partiallyComputedNode = new DoWhile(doCtx, this, body, condition);
throw;
}
else
{
if (JSToken.RightParenthesis == m_currentToken.Token)
GetNextToken();
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
if (JSToken.Semicolon == m_currentToken.Token)
{
// JScript 5 allowed statements like
// do{print(++x)}while(x<10) print(0)
// even though that does not strictly follow the automatic semicolon insertion
// rules for the required semi after the while(). For backwards compatibility
// we should continue to support this.
doCtx.UpdateWith(m_currentToken);
GetNextToken();
}
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return new DoWhile(doCtx, this, body, condition);
}
public void Visit(ConstantWrapper node)
{
// we're good
}
private ConstantWrapper UnsignedRightShift(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
try
{
// left-hand value is a 32-bit signed integer
UInt32 lvalue = left.ToUInt32();
// mask only the bottom 5 bits of the right-hand value
int rvalue = (int)(right.ToUInt32() & 0x1F);
// convert the result to a double
double result = Convert.ToDouble(lvalue >> rvalue);
newLiteral = new ConstantWrapper(result, PrimitiveType.Number, null, m_parser);
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
return newLiteral;
}
public override void CleanupNodes()
{
base.CleanupNodes();
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// see if our operand is a ConstantWrapper
ConstantWrapper literalOperand = Operand as ConstantWrapper;
if (literalOperand != null)
{
// must be number, boolean, string, or null
switch (OperatorToken)
{
case JSToken.Plus:
try
{
// replace with a constant representing operand.ToNumber,
Parent.ReplaceChild(this, new ConstantWrapper(literalOperand.ToNumber(), PrimitiveType.Number, Context, Parser));
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
break;
case JSToken.Minus:
try
{
// replace with a constant representing the negative of operand.ToNumber
Parent.ReplaceChild(this, new ConstantWrapper(-literalOperand.ToNumber(), PrimitiveType.Number, Context, Parser));
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
break;
case JSToken.BitwiseNot:
try
{
// replace with a constant representing the bitwise-not of operant.ToInt32
Parent.ReplaceChild(this, new ConstantWrapper(Convert.ToDouble(~literalOperand.ToInt32()), PrimitiveType.Number, Context, Parser));
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
break;
case JSToken.LogicalNot:
// replace with a constant representing the opposite of operand.ToBoolean
try
{
Parent.ReplaceChild(this, new ConstantWrapper(!literalOperand.ToBoolean(), PrimitiveType.Boolean, Context, Parser));
}
catch (InvalidCastException)
{
// ignore any invalid cast exceptions
}
break;
}
}
}
}
/// <summary>
/// Return true is not an overflow or underflow, for multiplication operations
/// </summary>
/// <param name="left">left operand</param>
/// <param name="right">right operand</param>
/// <param name="result">result</param>
/// <returns>true if result not overflow or underflow; false if it is</returns>
private static bool NoMultiplicativeOverOrUnderFlow(ConstantWrapper left, ConstantWrapper right, ConstantWrapper result)
{
// check for overflow
bool okayToProceed = !result.IsInfinity;
// if we still might be good, check for possible underflow
if (okayToProceed)
{
// if the result is zero, we might have an underflow. But if one of the operands
// was zero, then it's okay.
// Inverse: if neither operand is zero, then a zero result is not okay
okayToProceed = !result.IsZero || (left.IsZero || right.IsZero);
}
return okayToProceed;
}
// the global scope does nothing when told to add literals -- just returns null
internal override List <ConstantWrapper> AddLiteral(ConstantWrapper constantWrapper, ActivationObject refScope)
{
return(null);
}
/// <summary>
/// Return true if the result isn't an overflow condition
/// </summary>
/// <param name="result">result constant</param>
/// <returns>true is not an overflow; false if it is</returns>
private static bool NoOverflow(ConstantWrapper result)
{
return !result.IsInfinity;
}
/// <summary>
/// Eval the two constants: CONST [op] (OTHER [op] CONST)
/// </summary>
/// <param name="thisConstant">first constant</param>
/// <param name="otherConstant">second constant</param>
/// <param name="rightOperator">second operator</param>
private void EvalFarToTheRight(BinaryOperator node, ConstantWrapper thisConstant, ConstantWrapper otherConstant, BinaryOperator rightOperator)
{
if (rightOperator.OperatorToken == JSToken.Minus)
{
if (node.OperatorToken == JSToken.Plus)
{
// plus-minus
// our constant cannot be a string, though
if (!thisConstant.IsStringLiteral)
{
ConstantWrapper newLiteral = Minus(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
RotateFromLeft(node, rightOperator, newLiteral);
}
}
}
else if (node.OperatorToken == JSToken.Minus)
{
// minus-minus
ConstantWrapper newLiteral = NumericAddition(thisConstant, otherConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
// but we need to swap the left and right operands first
rightOperator.SwapOperands();
// then rotate the node up after replacing old with new
RotateFromRight(node, rightOperator, newLiteral);
}
}
}
else if (node.OperatorToken == JSToken.Multiply)
{
if (rightOperator.OperatorToken == JSToken.Multiply)
{
// mult-mult
ConstantWrapper newLiteral = Multiply(thisConstant, otherConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, newLiteral))
{
RotateFromLeft(node, rightOperator, newLiteral);
}
}
else if (rightOperator.OperatorToken == JSToken.Divide)
{
// mult-divide
ConstantWrapper otherOverThis = Divide(otherConstant, thisConstant);
ConstantWrapper thisOverOther = Divide(thisConstant, otherConstant);
int otherOverThisLength = otherOverThis != null ? otherOverThis.ToCode().Length : int.MaxValue;
int thisOverOtherLength = thisOverOther != null ? thisOverOther.ToCode().Length : int.MaxValue;
if (otherOverThis != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, otherOverThis)
&& (thisOverOther == null || otherOverThisLength < thisOverOtherLength))
{
if (otherOverThisLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// swap the operands, but keep the operator
RotateFromLeft(node, rightOperator, otherOverThis);
}
}
else if (thisOverOther != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, thisOverOther))
{
if (thisOverOtherLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// keep the order, but opposite operator
rightOperator.OperatorToken = JSToken.Multiply;
RotateFromRight(node, rightOperator, thisOverOther);
}
}
}
}
else if (node.OperatorToken == JSToken.Divide)
{
if (rightOperator.OperatorToken == JSToken.Multiply)
{
// divide-mult
ConstantWrapper newLiteral = Divide(thisConstant, otherConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, newLiteral)
&& newLiteral.ToCode().Length <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// swap the operands
rightOperator.SwapOperands();
// change the operator
rightOperator.OperatorToken = JSToken.Divide;
RotateFromRight(node, rightOperator, newLiteral);
}
}
else if (rightOperator.OperatorToken == JSToken.Divide)
{
// divide-divide
ConstantWrapper newLiteral = Multiply(thisConstant, otherConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, newLiteral))
{
// but we need to swap the left and right operands first
rightOperator.SwapOperands();
// then rotate the node up after replacing old with new
RotateFromRight(node, rightOperator, newLiteral);
}
}
}
}
// called during ConstantWrapper.AnalyzeNode
internal virtual List <ConstantWrapper> AddLiteral(ConstantWrapper constantWrapper, ActivationObject refScope)
{
List <ConstantWrapper> nodeList = null;
// numeric constants that are NaN or Infinity need not apply
if (!constantWrapper.IsSpecialNumeric)
{
// if the constant is only one character long, it's never a good idea to
// try and replace it
string constantValue = constantWrapper.ToCode();
if (constantValue.Length > 1)
{
// go up the chain recursively. return the highest shared
// constant node list so we can share it if we need to
nodeList = ((ActivationObject)Parent).AddLiteral(constantWrapper, this);
// if we haven't created our literal map yet, do so now
if (m_literalMap == null)
{
m_literalMap = new Dictionary <string, LiteralReference>();
}
// now handle our scope
LiteralReference literalReference;
// see if this constant is in our map
if (m_literalMap.ContainsKey(constantValue))
{
literalReference = m_literalMap[constantValue];
// increment the counter
literalReference.Increment();
// add this constant wrapper to the list
if (!literalReference.ConstantWrapperList.Contains(constantWrapper))
{
literalReference.ConstantWrapperList.Add(constantWrapper);
}
// if this is the ref scope, or if the ref scope is not the child scope,
// set the child scope to null
if (literalReference.ChildScope != null &&
(refScope == this || refScope != literalReference.ChildScope))
{
literalReference.ChildScope = null;
}
}
else
{
// add to the table with count = 1 and our given constant wrapper
// if this is the ref scope, child scope is null; otherwise use refScope
// if nodelist is null, create a new list; otherwise use the shared list
literalReference = new LiteralReference(
constantWrapper,
(refScope != this ? refScope : null),
nodeList
);
m_literalMap.Add(constantValue, literalReference);
}
// return whatever list it is we used for our node.
// it might be shared, or it might be new if we didn't find a shared list
nodeList = literalReference.ConstantWrapperList;
}
}
return(nodeList);
}
// the global scope does nothing when told to add literals -- just returns null
internal override List<ConstantWrapper> AddLiteral(ConstantWrapper constantWrapper, ActivationObject refScope)
{
return null;
}
private ConstantWrapper Divide(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (left.IsOkayToCombine && right.IsOkayToCombine
&& m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
try
{
double leftValue = left.ToNumber();
double rightValue = right.ToNumber();
double result = leftValue / rightValue;
if (ConstantWrapper.NumberIsOkayToCombine(result))
{
newLiteral = new ConstantWrapper(result, PrimitiveType.Number, null, m_parser);
}
else
{
if (!left.IsNumericLiteral && ConstantWrapper.NumberIsOkayToCombine(leftValue))
{
left.Parent.ReplaceChild(left, new ConstantWrapper(leftValue, PrimitiveType.Number, left.Context, m_parser));
}
if (!right.IsNumericLiteral && ConstantWrapper.NumberIsOkayToCombine(rightValue))
{
right.Parent.ReplaceChild(right, new ConstantWrapper(rightValue, PrimitiveType.Number, right.Context, m_parser));
}
}
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
return newLiteral;
}
private ConstantWrapper StringConcat(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
// if we don't want to combine adjacent string literals, then we know we don't want to do
// anything here.
if (m_parser.Settings.IsModificationAllowed(TreeModifications.CombineAdjacentStringLiterals))
{
// if either one of the operands is not a string literal, then check to see if we allow
// evaluation of numeric expression; if not, then no-go. IF they are both string literals,
// then it doesn't matter what the numeric flag says.
if ((left.IsStringLiteral && right.IsStringLiteral)
|| m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// if either value is a floating-point number (a number, not NaN, not Infinite, not an Integer),
// then we won't do the string concatenation because different browsers may have subtle differences
// in their double-to-string conversion algorithms.
// so if neither is a numeric literal, or if one or both are, if they are both integer literals
// in the range that we can EXACTLY represent them in a double, then we can proceed.
// NaN, +Infinity and -Infinity are also acceptable
if ((!left.IsNumericLiteral || left.IsExactInteger || left.IsNaN || left.IsInfinity)
&& (!right.IsNumericLiteral || right.IsExactInteger || right.IsNaN || right.IsInfinity))
{
// they are both either string, bool, null, or integer
newLiteral = new ConstantWrapper(left.ToString() + right.ToString(), PrimitiveType.String, null, m_parser);
}
}
}
return newLiteral;
}
//---------------------------------------------------------------------------------------
// ParseWhileStatement
//
// WhileStatement :
// 'while' '(' Expression ')' Statement
//---------------------------------------------------------------------------------------
private WhileNode ParseWhileStatement()
{
Context whileCtx = m_currentToken.Clone();
AstNode condition = null;
AstNode body = null;
m_blockType.Add(BlockType.Loop);
try
{
GetNextToken();
if (JSToken.LeftParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoLeftParenthesis);
}
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
condition = ParseExpression();
if (JSToken.RightParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoRightParenthesis);
whileCtx.UpdateWith(condition.Context);
}
else
whileCtx.UpdateWith(m_currentToken);
GetNextToken();
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
// abort the while there is really no much to do here
exc._partiallyComputedNode = null;
throw;
}
else
{
// make up a condition
if (exc._partiallyComputedNode != null)
condition = exc._partiallyComputedNode;
else
condition = new ConstantWrapper(false, PrimitiveType.Boolean, CurrentPositionContext(), this);
if (JSToken.RightParenthesis == m_currentToken.Token)
GetNextToken();
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, whileCtx, true);
}
try
{
// parse a Statement, not a SourceElement
body = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode != null)
body = exc._partiallyComputedNode;
else
body = new Block(CurrentPositionContext(), this);
exc._partiallyComputedNode = new WhileNode(whileCtx, this, condition, body);
throw;
}
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return new WhileNode(whileCtx, this, condition, body);
}
/// <summary>
/// We have determined that our right-hand operand is another binary operator, and its
/// left-hand operand is a constant that can be combined with our left-hand operand.
/// Now we want to set the left-hand operand of that other operator to the newly-
/// combined constant value, and then rotate it up -- replace our binary operator
/// with this newly-modified binary operator, and then attempt to re-evaluate it.
/// </summary>
/// <param name="binaryOp">the binary operator that is our right-hand operand</param>
/// <param name="newLiteral">the newly-combined literal</param>
private void RotateFromRight(BinaryOperator node, BinaryOperator binaryOp, ConstantWrapper newLiteral)
{
// replace our node with the binary operator
binaryOp.ReplaceChild(binaryOp.Operand1, newLiteral);
node.Parent.ReplaceChild(node, binaryOp);
// and just for good measure.. revisit the node that's taking our place, since
// we just changed a constant value. Assuming the other operand is a constant, too.
ConstantWrapper otherConstant = binaryOp.Operand2 as ConstantWrapper;
if (otherConstant != null)
{
EvalThisOperator(binaryOp, newLiteral, otherConstant);
}
}
//---------------------------------------------------------------------------------------
// ParseSwitchStatement
//
// SwitchStatement :
// 'switch' '(' Expression ')' '{' CaseBlock '}'
//
// CaseBlock :
// CaseList DefaultCaseClause CaseList
//
// CaseList :
// <empty> |
// CaseClause CaseList
//
// CaseClause :
// 'case' Expression ':' OptionalStatements
//
// DefaultCaseClause :
// <empty> |
// 'default' ':' OptionalStatements
//---------------------------------------------------------------------------------------
private AstNode ParseSwitchStatement()
{
Context switchCtx = m_currentToken.Clone();
AstNode expr = null;
AstNodeList cases = null;
m_blockType.Add(BlockType.Switch);
try
{
// read switch(expr)
GetNextToken();
if (JSToken.LeftParenthesis != m_currentToken.Token)
ReportError(JSError.NoLeftParenthesis);
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
m_noSkipTokenSet.Add(NoSkipTokenSet.s_SwitchNoSkipTokenSet);
try
{
expr = ParseExpression();
if (JSToken.RightParenthesis != m_currentToken.Token)
{
ReportError(JSError.NoRightParenthesis);
}
GetNextToken();
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.NoLeftCurly);
}
GetNextToken();
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1
&& IndexOfToken(NoSkipTokenSet.s_SwitchNoSkipTokenSet, exc) == -1)
{
// give up
exc._partiallyComputedNode = null;
throw;
}
else
{
if (exc._partiallyComputedNode == null)
expr = new ConstantWrapper(true, PrimitiveType.Boolean, CurrentPositionContext(), this);
else
expr = exc._partiallyComputedNode;
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) != -1)
{
if (exc._token == JSToken.RightParenthesis)
GetNextToken();
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.NoLeftCurly);
}
GetNextToken();
}
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_SwitchNoSkipTokenSet);
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
// parse the switch body
cases = new AstNodeList(m_currentToken.Clone(), this);
bool defaultStatement = false;
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockNoSkipTokenSet);
try
{
while (JSToken.RightCurly != m_currentToken.Token)
{
SwitchCase caseClause = null;
AstNode caseValue = null;
Context caseCtx = m_currentToken.Clone();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_CaseNoSkipTokenSet);
try
{
if (JSToken.Case == m_currentToken.Token)
{
// get the case
GetNextToken();
caseValue = ParseExpression();
}
else if (JSToken.Default == m_currentToken.Token)
{
// get the default
if (defaultStatement)
{
// we report an error but we still accept the default
ReportError(JSError.DupDefault, true);
}
else
{
defaultStatement = true;
}
GetNextToken();
}
else
{
// This is an error, there is no case or default. Assume a default was missing and keep going
defaultStatement = true;
ReportError(JSError.BadSwitch);
}
if (JSToken.Colon != m_currentToken.Token)
{
ReportError(JSError.NoColon);
}
// read the statements inside the case or default
GetNextToken();
}
catch (RecoveryTokenException exc)
{
// right now we can only get here for the 'case' statement
if (IndexOfToken(NoSkipTokenSet.s_CaseNoSkipTokenSet, exc) == -1)
{
// ignore the current case or default
exc._partiallyComputedNode = null;
throw;
}
else
{
caseValue = exc._partiallyComputedNode;
if (exc._token == JSToken.Colon)
{
GetNextToken();
}
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_CaseNoSkipTokenSet);
}
m_blockType.Add(BlockType.Block);
try
{
Block statements = new Block(m_currentToken.Clone(), this);
m_noSkipTokenSet.Add(NoSkipTokenSet.s_SwitchNoSkipTokenSet);
m_noSkipTokenSet.Add(NoSkipTokenSet.s_StartStatementNoSkipTokenSet);
try
{
while (JSToken.RightCurly != m_currentToken.Token && JSToken.Case != m_currentToken.Token && JSToken.Default != m_currentToken.Token)
{
try
{
// parse a Statement, not a SourceElement
statements.Append(ParseStatement(false));
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode != null)
{
statements.Append(exc._partiallyComputedNode);
exc._partiallyComputedNode = null;
}
if (IndexOfToken(NoSkipTokenSet.s_StartStatementNoSkipTokenSet, exc) == -1)
{
throw;
}
}
}
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_SwitchNoSkipTokenSet, exc) == -1)
{
caseClause = new SwitchCase(caseCtx, this, caseValue, statements);
cases.Append(caseClause);
throw;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_StartStatementNoSkipTokenSet);
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_SwitchNoSkipTokenSet);
}
if (JSToken.RightCurly == m_currentToken.Token)
{
statements.Context.UpdateWith(m_currentToken);
}
caseCtx.UpdateWith(statements.Context);
caseClause = new SwitchCase(caseCtx, this, caseValue, statements);
cases.Append(caseClause);
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
}
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockNoSkipTokenSet, exc) == -1)
{
//save what you can a rethrow
switchCtx.UpdateWith(CurrentPositionContext());
exc._partiallyComputedNode = new Switch(switchCtx, this, expr, cases);
throw;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockNoSkipTokenSet);
}
switchCtx.UpdateWith(m_currentToken);
GetNextToken();
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return new Switch(switchCtx, this, expr, cases);
}
/// <summary>
/// If the new literal is a string literal, then we need to check to see if our
/// parent is a CallNode. If it is, and if the string literal can be an identifier,
/// we'll replace it with a Member-Dot operation.
/// </summary>
/// <param name="newLiteral">newLiteral we intend to replace this binaryop node with</param>
/// <returns>true if we replaced the parent callnode with a member-dot operation</returns>
private bool ReplaceMemberBracketWithDot(BinaryOperator node, ConstantWrapper newLiteral)
{
if (newLiteral.IsStringLiteral)
{
// see if this newly-combined string is the sole argument to a
// call-brackets node. If it is and the combined string is a valid
// identifier (and not a keyword), then we can replace the call
// with a member operator.
// remember that the parent of the argument won't be the call node -- it
// will be the ast node list representing the arguments, whose parent will
// be the node list.
CallNode parentCall = (node.Parent is AstNodeList ? node.Parent.Parent as CallNode : null);
if (parentCall != null && parentCall.InBrackets)
{
// get the newly-combined string
string combinedString = newLiteral.ToString();
// see if this new string is the target of a replacement operation
string newName;
if (m_parser.Settings.HasRenamePairs && m_parser.Settings.ManualRenamesProperties
&& m_parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming)
&& !string.IsNullOrEmpty(newName = m_parser.Settings.GetNewName(combinedString)))
{
// yes, it is. Now see if the new name is safe to be converted to a dot-operation.
if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember)
&& JSScanner.IsSafeIdentifier(newName)
&& !JSScanner.IsKeyword(newName, parentCall.EnclosingScope.UseStrict))
{
// we want to replace the call with operator with a new member dot operation, and
// since we won't be analyzing it (we're past the analyze phase, we're going to need
// to use the new string value
Member replacementMember = new Member(parentCall.Context, m_parser, parentCall.Function, newName, parentCall.Arguments[0].Context);
parentCall.Parent.ReplaceChild(parentCall, replacementMember);
return true;
}
else
{
// nope, can't be changed to a dot-operator for whatever reason.
// just replace the value on this new literal. The old operation will
// get replaced with this new literal
newLiteral.Value = newName;
// and make sure it's type is string
newLiteral.PrimitiveType = PrimitiveType.String;
}
}
else if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember))
{
// our parent is a call-bracket -- now we just need to see if the newly-combined
// string can be an identifier
if (JSScanner.IsSafeIdentifier(combinedString) && !JSScanner.IsKeyword(combinedString, parentCall.EnclosingScope.UseStrict))
{
// yes -- replace the parent call with a new member node using the newly-combined string
Member replacementMember = new Member(parentCall.Context, m_parser, parentCall.Function, combinedString, parentCall.Arguments[0].Context);
parentCall.Parent.ReplaceChild(parentCall, replacementMember);
return true;
}
}
}
}
return false;
}
//---------------------------------------------------------------------------------------
// MemberExpression
//
// Accessor :
// <empty> |
// Arguments Accessor
// '[' Expression ']' Accessor |
// '.' Identifier Accessor |
//
// Don't have this function throwing an exception without checking all the calling sites.
// There is state in instance variable that is saved on the calling stack in some function
// (i.e ParseFunction and ParseClass) and you don't want to blow up the stack
//---------------------------------------------------------------------------------------
private AstNode MemberExpression(AstNode expression, List<Context> newContexts)
{
for (; ; )
{
m_noSkipTokenSet.Add(NoSkipTokenSet.s_MemberExprNoSkipTokenSet);
try
{
switch (m_currentToken.Token)
{
case JSToken.LeftParenthesis:
AstNodeList args = null;
RecoveryTokenException callError = null;
m_noSkipTokenSet.Add(NoSkipTokenSet.s_ParenToken);
try
{
args = ParseExpressionList(JSToken.RightParenthesis);
}
catch (RecoveryTokenException exc)
{
args = (AstNodeList)exc._partiallyComputedNode;
if (IndexOfToken(NoSkipTokenSet.s_ParenToken, exc) == -1)
callError = exc; // thrown later on
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_ParenToken);
}
expression = new CallNode(expression.Context.CombineWith(args.Context), this, expression, args, false);
if (null != newContexts && newContexts.Count > 0)
{
(newContexts[newContexts.Count - 1]).UpdateWith(expression.Context);
if (!(expression is CallNode))
expression = new CallNode(newContexts[newContexts.Count - 1], this, expression, new AstNodeList(CurrentPositionContext(), this), false);
else
expression.Context = newContexts[newContexts.Count - 1];
((CallNode)expression).IsConstructor = true;
newContexts.RemoveAt(newContexts.Count - 1);
}
if (callError != null)
{
callError._partiallyComputedNode = expression;
throw callError;
}
GetNextToken();
break;
case JSToken.LeftBracket:
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BracketToken);
try
{
//
// ROTOR parses a[b,c] as a call to a, passing in the arguments b and c.
// the correct parse is a member lookup on a of c -- the "b,c" should be
// a single expression with a comma operator that evaluates b but only
// returns c.
// So we'll change the default behavior from parsing an expression list to
// parsing a single expression, but returning a single-item list (or an empty
// list if there is no expression) so the rest of the code will work.
//
//args = ParseExpressionList(JSToken.RightBracket);
GetNextToken();
args = new AstNodeList(m_currentToken.Clone(), this);
AstNode accessor = ParseExpression();
if (accessor != null)
{
args.Append(accessor);
}
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BracketToken, exc) == -1)
{
if (exc._partiallyComputedNode != null)
{
exc._partiallyComputedNode =
new CallNode(expression.Context.CombineWith(m_currentToken.Clone()), this, expression, (AstNodeList)exc._partiallyComputedNode, true);
}
else
{
exc._partiallyComputedNode = expression;
}
throw;
}
else
args = (AstNodeList)exc._partiallyComputedNode;
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BracketToken);
}
expression = new CallNode(expression.Context.CombineWith(m_currentToken.Clone()), this, expression, args, true);
// there originally was code here in the ROTOR sources that checked the new context list and
// changed this member call to a constructor call, effectively combining the two. I believe they
// need to remain separate.
// remove the close bracket token
GetNextToken();
break;
case JSToken.AccessField:
ConstantWrapper id = null;
GetNextToken();
if (JSToken.Identifier != m_currentToken.Token)
{
string identifier = JSKeyword.CanBeIdentifier(m_currentToken.Token);
if (null != identifier)
{
// don't report an error here -- it's actually okay to have a property name
// that is a keyword which is okay to be an identifier. For instance,
// jQuery has a commonly-used method named "get" to make an ajax request
//ForceReportInfo(JSError.KeywordUsedAsIdentifier);
id = new ConstantWrapper(identifier, PrimitiveType.String, m_currentToken.Clone(), this);
}
else if (JSScanner.IsValidIdentifier(m_currentToken.Code))
{
// it must be a keyword, because it can't technically be an indentifier,
// but it IS a valid identifier format. Throw the error but still
// create the constant wrapper so we can output it as-is
ReportError(JSError.NoIdentifier, m_currentToken.Clone(), true);
id = new ConstantWrapper(m_currentToken.Code, PrimitiveType.String, m_currentToken.Clone(), this);
}
else
{
ReportError(JSError.NoIdentifier);
SkipTokensAndThrow(expression);
}
}
else
{
id = new ConstantWrapper(m_scanner.GetIdentifier(), PrimitiveType.String, m_currentToken.Clone(), this);
}
GetNextToken();
expression = new Member(expression.Context.CombineWith(id.Context), this, expression, id.Context.Code, id.Context);
break;
default:
if (null != newContexts)
{
while (newContexts.Count > 0)
{
(newContexts[newContexts.Count - 1]).UpdateWith(expression.Context);
expression = new CallNode(newContexts[newContexts.Count - 1],
this,
expression,
new AstNodeList(CurrentPositionContext(), this),
false);
((CallNode)expression).IsConstructor = true;
newContexts.RemoveAt(newContexts.Count - 1);
}
}
return expression;
}
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_MemberExprNoSkipTokenSet, exc) != -1)
expression = exc._partiallyComputedNode;
else
{
Debug.Assert(exc._partiallyComputedNode == expression);
throw;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_MemberExprNoSkipTokenSet);
}
}
}
private static string CreateJSFromResourceStrings(ResourceStrings resourceStrings)
{
var sb = StringBuilderPool.Acquire();
try
{
// start the var statement using the requested name and open the initializer object literal
sb.Append("var ");
sb.Append(resourceStrings.Name);
sb.Append("={");
// we're going to need to insert commas between each pair, so we'll use a boolean
// flag to indicate that we're on the first pair. When we output the first pair, we'll
// set the flag to false. When the flag is false, we're about to insert another pair, so
// we'll add the comma just before.
bool firstItem = true;
// loop through all items in the collection
foreach (var keyPair in resourceStrings.NameValuePairs)
{
// if this isn't the first item, we need to add a comma separator
if (!firstItem)
{
sb.Append(',');
}
else
{
// next loop is no longer the first item
firstItem = false;
}
// append the key as the name, a colon to separate the name and value,
// and then the value
// must quote if not valid JS identifier format, or if it is, but it's a keyword
// (use strict mode just to be safe)
string propertyName = keyPair.Key;
if (!JSScanner.IsValidIdentifier(propertyName) || JSScanner.IsKeyword(propertyName, true))
{
sb.Append("\"");
// because we are using quotes for the delimiters, replace any instances
// of a quote character (") with an escaped quote character (\")
sb.Append(propertyName.Replace("\"", "\\\""));
sb.Append("\"");
}
else
{
sb.Append(propertyName);
}
sb.Append(':');
// make sure the Value is properly escaped, quoted, and whatever we
// need to do to make sure it's a proper JS string.
// pass false for whether this string is an argument to a RegExp constructor.
// pass false for whether to use W3Strict formatting for character escapes (use maximum browser compatibility)
// pass true for ecma strict mode
string stringValue = ConstantWrapper.EscapeString(
keyPair.Value,
false,
false,
true
);
sb.Append(stringValue);
}
// close the object literal and return the string
sb.AppendLine("};");
return(sb.ToString());
}
finally
{
sb.Release();
}
}
private ConstantWrapper Plus(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (left.IsStringLiteral || right.IsStringLiteral)
{
// one or both are strings -- this is a strng concat operation
newLiteral = StringConcat(left, right);
}
else
{
// neither are strings -- this is a numeric addition operation
newLiteral = NumericAddition(left, right);
}
return newLiteral;
}
private ConstantWrapper Equal(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
PrimitiveType leftType = left.PrimitiveType;
if (leftType == right.PrimitiveType)
{
// the values are the same type
switch (leftType)
{
case PrimitiveType.Null:
// null == null is true
newLiteral = new ConstantWrapper(true, PrimitiveType.Boolean, null, m_parser);
break;
case PrimitiveType.Boolean:
// compare boolean values
newLiteral = new ConstantWrapper(left.ToBoolean() == right.ToBoolean(), PrimitiveType.Boolean, null, m_parser);
break;
case PrimitiveType.String:
// compare string ordinally
newLiteral = new ConstantWrapper(string.CompareOrdinal(left.ToString(), right.ToString()) == 0, PrimitiveType.Boolean, null, m_parser);
break;
case PrimitiveType.Number:
try
{
// compare the values
// +0 and -0 are treated as "equal" in C#, so we don't need to test them separately.
// and NaN is always unequal to everything else, including itself.
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(left.ToNumber() == right.ToNumber(), PrimitiveType.Boolean, null, m_parser);
}
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
break;
}
}
else if (left.IsOkayToCombine && right.IsOkayToCombine)
{
try
{
// numeric comparison
// +0 and -0 are treated as "equal" in C#, so we don't need to test them separately.
// and NaN is always unequal to everything else, including itself.
newLiteral = new ConstantWrapper(left.ToNumber() == right.ToNumber(), PrimitiveType.Boolean, null, m_parser);
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
}
return newLiteral;
}
public override void CleanupNodes()
{
base.CleanupNodes();
// see if the condition is a constant
if (Parser.Settings.EvalLiteralExpressions &&
Parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
ConstantWrapper constantCondition = Condition as ConstantWrapper;
if (constantCondition != null)
{
// TODO: we'd RATHER eliminate the statement altogether if the condition is always false,
// but we'd need to make sure var'd variables and declared functions are properly handled.
try
{
bool isTrue = constantCondition.ToBoolean();
if (isTrue)
{
// the condition is always true; we should change it to a for(;;) statement.
// less bytes than while(1)
// check to see if we want to combine a preceding var with a for-statement
AstNode initializer = null;
if (Parser.Settings.IsModificationAllowed(TreeModifications.MoveVarIntoFor))
{
// if the previous statement is a var, we can move it to the initializer
// and save even more bytes. The parent should always be a block. If not,
// then assume there is no previous.
Block parentBlock = Parent as Block;
if (parentBlock != null)
{
int whileIndex = parentBlock.StatementIndex(this);
if (whileIndex > 0)
{
Var previousVar = parentBlock[whileIndex - 1] as Var;
if (previousVar != null)
{
initializer = previousVar;
parentBlock.ReplaceChild(previousVar, null);
}
}
}
}
// create the for using our body and replace ourselves with it
ForNode forNode = new ForNode(Context, Parser, initializer, null, null, Body);
Parent.ReplaceChild(this, forNode);
}
else if (constantCondition.IsNotOneOrPositiveZero)
{
// the condition is always false, so we can replace the condition
// with a zero -- only one byte
Condition = new ConstantWrapper(0, PrimitiveType.Number, null, Parser);
}
}
catch (InvalidCastException)
{
// ignore any invalid cast exceptions
}
}
}
}
/// <summary>
/// Evaluate: (OTHER [op] CONST) [op] CONST
/// </summary>
/// <param name="thisConstant">second constant</param>
/// <param name="otherConstant">first constant</param>
/// <param name="leftOperator">first operator</param>
private void EvalToTheLeft(BinaryOperator node, ConstantWrapper thisConstant, ConstantWrapper otherConstant, BinaryOperator leftOperator)
{
if (leftOperator.OperatorToken == JSToken.Plus && node.OperatorToken == JSToken.Plus)
{
// plus-plus
// the other operation goes first, so if the other constant is a string, then we know that
// operation will do a string concatenation, which will force our operation to be a string
// concatenation. If the other constant is not a string, then we won't know until runtime and
// we can't combine them.
if (otherConstant.IsStringLiteral)
{
// the other constant is a string -- so we can do the string concat and combine them
ConstantWrapper newLiteral = StringConcat(otherConstant, thisConstant);
if (newLiteral != null)
{
RotateFromLeft(node, leftOperator, newLiteral);
}
}
}
else if (leftOperator.OperatorToken == JSToken.Minus)
{
if (node.OperatorToken == JSToken.Plus)
{
// minus-plus
// the minus operator goes first and will always convert to number.
// if our constant is not a string, then it will be a numeric addition and we can combine them.
// if our constant is a string, then we'll end up doing a string concat, so we can't combine
if (!thisConstant.IsStringLiteral)
{
// two numeric operators. a-n1+n2 is the same as a-(n1-n2)
ConstantWrapper newLiteral = Minus(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
// a-(-n) is numerically equivalent as a+n -- and takes fewer characters to represent.
// BUT we can't do that because that might change a numeric operation (the original minus)
// to a string concatenation if the unknown operand turns out to be a string!
RotateFromLeft(node, leftOperator, newLiteral);
}
else
{
// if the left-left is a constant, then we can try combining with it
ConstantWrapper leftLeft = leftOperator.Operand1 as ConstantWrapper;
if (leftLeft != null)
{
EvalFarToTheLeft(node, thisConstant, leftLeft, leftOperator);
}
}
}
}
else if (node.OperatorToken == JSToken.Minus)
{
// minus-minus. Both operations are numeric.
// a-n1-n2 => a-(n1+n2), so we can add the two constants and subtract from
// the left-hand non-constant.
ConstantWrapper newLiteral = NumericAddition(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
// make it the new right-hand literal for the left-hand operator
// and make the left-hand operator replace our operator
RotateFromLeft(node, leftOperator, newLiteral);
}
else
{
// if the left-left is a constant, then we can try combining with it
ConstantWrapper leftLeft = leftOperator.Operand1 as ConstantWrapper;
if (leftLeft != null)
{
EvalFarToTheLeft(node, thisConstant, leftLeft, leftOperator);
}
}
}
}
else if (leftOperator.OperatorToken == node.OperatorToken
&& (node.OperatorToken == JSToken.Multiply || node.OperatorToken == JSToken.Divide))
{
// either multiply-multiply or divide-divide
// either way, we use the other operand and the product of the two constants.
// if the product blows up to an infinte value, then don't combine them because that
// could change the way the program goes at runtime, depending on the unknown value.
ConstantWrapper newLiteral = Multiply(otherConstant, thisConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, newLiteral))
{
RotateFromLeft(node, leftOperator, newLiteral);
}
}
else if ((leftOperator.OperatorToken == JSToken.Multiply && node.OperatorToken == JSToken.Divide)
|| (leftOperator.OperatorToken == JSToken.Divide && node.OperatorToken == JSToken.Multiply))
{
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// get the two division operators
ConstantWrapper otherOverThis = Divide(otherConstant, thisConstant);
ConstantWrapper thisOverOther = Divide(thisConstant, otherConstant);
// get the lengths
int otherOverThisLength = otherOverThis != null ? otherOverThis.ToCode().Length : int.MaxValue;
int thisOverOtherLength = thisOverOther != null ? thisOverOther.ToCode().Length : int.MaxValue;
// we'll want to use whichever one is shorter, and whichever one does NOT involve an overflow
// or possible underflow
if (otherOverThis != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, otherOverThis)
&& (thisOverOther == null || otherOverThisLength < thisOverOtherLength))
{
// but only if it's smaller than the original expression
if (otherOverThisLength <= otherConstant.ToCode().Length + thisConstant.ToCode().Length + 1)
{
// same operator
RotateFromLeft(node, leftOperator, otherOverThis);
}
}
else if (thisOverOther != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, thisOverOther))
{
// but only if it's smaller than the original expression
if (thisOverOtherLength <= otherConstant.ToCode().Length + thisConstant.ToCode().Length + 1)
{
// opposite operator
leftOperator.OperatorToken = leftOperator.OperatorToken == JSToken.Multiply ? JSToken.Divide : JSToken.Multiply;
RotateFromLeft(node, leftOperator, thisOverOther);
}
}
}
}
else if (node.OperatorToken == leftOperator.OperatorToken
&& (node.OperatorToken == JSToken.BitwiseAnd || node.OperatorToken == JSToken.BitwiseOr || node.OperatorToken == JSToken.BitwiseXor))
{
// identical bitwise operators can be combined
ConstantWrapper newLiteral = null;
switch (node.OperatorToken)
{
case JSToken.BitwiseAnd:
newLiteral = BitwiseAnd(otherConstant, thisConstant);
break;
case JSToken.BitwiseOr:
newLiteral = BitwiseOr(otherConstant, thisConstant);
break;
case JSToken.BitwiseXor:
newLiteral = BitwiseXor(otherConstant, thisConstant);
break;
}
if (newLiteral != null)
{
RotateFromLeft(node, leftOperator, newLiteral);
}
}
}
private ConstantWrapper LessThanOrEqual(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
if (left.IsStringLiteral && right.IsStringLiteral)
{
// do a straight ordinal comparison of the strings
newLiteral = new ConstantWrapper(string.CompareOrdinal(left.ToString(), right.ToString()) <= 0, PrimitiveType.Boolean, null, m_parser);
}
else
{
try
{
// either one or both are NOT a string -- numeric comparison
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(left.ToNumber() <= right.ToNumber(), PrimitiveType.Boolean, null, m_parser);
}
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
}
return newLiteral;
}
public override void Visit(ConstantWrapper node)
{
if (node != null)
{
// check to see if this node is an argument to a RegExp constructor.
// if it is, we'll want to not use certain string escapes
AstNode previousNode = null;
AstNode parentNode = node.Parent;
while (parentNode != null)
{
// is this a call node and the previous node was one of the parameters?
CallNode callNode = parentNode as CallNode;
if (callNode != null && previousNode == callNode.Arguments)
{
// are we calling a simple lookup for "RegExp"?
Lookup lookup = callNode.Function as Lookup;
if (lookup != null && lookup.Name == "RegExp")
{
// we are -- so all string literals passed within this constructor should not use
// standard string escape sequences
node.IsParameterToRegExp = true;
// we can stop looking
break;
}
}
// next up the chain, keeping track of this current node as next iteration's "previous" node
previousNode = parentNode;
parentNode = parentNode.Parent;
}
// we only need to process the literals IF we are actually going to do
// anything with them (combine duplicates). So if we aren't, don't call
// AddLiteral because it hugely inflates the processing time of the application.
if (m_parser.Settings.CombineDuplicateLiterals)
{
// add this literal to the scope's literal collection.
// HOWEVER, we do NOT want to add it for consideration of literal combination
// if any scope above us is a with-scope -- otherwise the
// variable we use to combine the literals might be confused with a
// property on the with-object.
// AND we don't want to do it if the scope is unknown, for the same reason.
// we won't really know if the variable we create will interfere with the
// scope resolution of any variables that me in the eval string.
ActivationObject thisScope = ScopeStack.Peek();
if (thisScope.IsKnownAtCompileTime && !thisScope.IsInWithScope)
{
thisScope.AddLiteral(node, thisScope);
}
}
// this node has no children, so don't bother calling the base
//base.Visit(node);
}
}
internal override void AnalyzeNode()
{
// see if this is a member (we'll need it for a couple checks)
Member member = m_func as Member;
if (Parser.Settings.StripDebugStatements && Parser.Settings.IsModificationAllowed(TreeModifications.StripDebugStatements))
{
// if this is a member, and it's a debugger object, and it's a constructor....
if (member != null && member.IsDebuggerStatement && m_isConstructor)
{
// we need to replace our debugger object with a generic Object
m_func = new Lookup("Object", m_func.Context, Parser);
// and make sure the node list is empty
if (m_args != null && m_args.Count > 0)
{
m_args = new AstNodeList(m_args.Context, Parser);
}
}
}
// if this is a constructor and we want to collapse
// some of them to literals...
if (m_isConstructor && Parser.Settings.CollapseToLiteral)
{
// see if this is a lookup, and if so, if it's pointing to one
// of the two constructors we want to collapse
Lookup lookup = m_func as Lookup;
if (lookup != null)
{
if (lookup.Name == "Object" &&
Parser.Settings.IsModificationAllowed(TreeModifications.NewObjectToObjectLiteral))
{
// no arguments -- the Object constructor with no arguments is the exact same as an empty
// object literal
if (m_args == null || m_args.Count == 0)
{
// replace our node with an object literal
ObjectLiteral objLiteral = new ObjectLiteral(Context, Parser, null, null);
if (Parent.ReplaceChild(this, objLiteral))
{
// and bail now. No need to recurse -- it's an empty literal
return;
}
}
else if (m_args.Count == 1)
{
// one argument
// check to see if it's an object literal.
ObjectLiteral objectLiteral = m_args[0] as ObjectLiteral;
if (objectLiteral != null)
{
// the Object constructor with an argument that is a JavaScript object merely returns the
// argument. Since the argument is an object literal, it is by definition a JavaScript object
// and therefore we can replace the constructor call with the object literal
Parent.ReplaceChild(this, objectLiteral);
// don't forget to recurse the object now
objectLiteral.AnalyzeNode();
// and then bail -- we don't want to process this call
// operation any more; we've gotten rid of it
return;
}
}
}
else if (lookup.Name == "Array" &&
Parser.Settings.IsModificationAllowed(TreeModifications.NewArrayToArrayLiteral))
{
// Array is trickier.
// If there are no arguments, then just use [].
// if there are multiple arguments, then use [arg0,arg1...argN].
// but if there is one argument and it's numeric, we can't crunch it.
// also can't crunch if it's a function call or a member or something, since we won't
// KNOW whether or not it's numeric.
//
// so first see if it even is a single-argument constant wrapper.
ConstantWrapper constWrapper = (m_args != null && m_args.Count == 1 ? m_args[0] as ConstantWrapper : null);
// if the argument count is not one, then we crunch.
// if the argument count IS one, we only crunch if we have a constant wrapper,
// AND it's not numeric.
if (m_args == null ||
m_args.Count != 1 ||
(constWrapper != null && !constWrapper.IsNumericLiteral))
{
// create the new array literal object
ArrayLiteral arrayLiteral = new ArrayLiteral(Context, Parser, m_args);
// replace ourself within our parent
if (Parent.ReplaceChild(this, arrayLiteral))
{
// recurse
arrayLiteral.AnalyzeNode();
// and bail -- we don't want to recurse this node any more
return;
}
}
}
}
}
// if we are replacing resource references with strings generated from resource files
// and this is a brackets call: lookup[args]
ResourceStrings resourceStrings = Parser.ResourceStrings;
if (m_inBrackets && resourceStrings != null && resourceStrings.Count > 0)
{
// see if the root object is a lookup that corresponds to the
// global value (not a local field) for our resource object
// (same name)
Lookup rootLookup = m_func as Lookup;
if (rootLookup != null &&
rootLookup.LocalField == null &&
string.CompareOrdinal(rootLookup.Name, resourceStrings.Name) == 0)
{
// we're going to replace this node with a string constant wrapper
// but first we need to make sure that this is a valid lookup.
// if the parameter contains anything that would vary at run-time,
// then we need to throw an error.
// the parser will always have either one or zero nodes in the arguments
// arg list. We're not interested in zero args, so just make sure there is one
if (m_args.Count == 1)
{
// must be a constant wrapper
ConstantWrapper argConstant = m_args[0] as ConstantWrapper;
if (argConstant != null)
{
string resourceName = argConstant.Value.ToString();
// get the localized string from the resources object
ConstantWrapper resourceLiteral = new ConstantWrapper(
resourceStrings[resourceName],
PrimitiveType.String,
Context,
Parser);
// replace this node with localized string, analyze it, and bail
// so we don't anaylze the tree we just replaced
Parent.ReplaceChild(this, resourceLiteral);
resourceLiteral.AnalyzeNode();
return;
}
else
{
// error! must be a constant
Context.HandleError(
JSError.ResourceReferenceMustBeConstant,
true);
}
}
else
{
// error! can only be a single constant argument to the string resource object.
// the parser will only have zero or one arguments, so this must be zero
// (since the parser won't pass multiple args to a [] operator)
Context.HandleError(
JSError.ResourceReferenceMustBeConstant,
true);
}
}
}
// and finally, if this is a backets call and the argument is a constantwrapper that can
// be an identifier, just change us to a member node: obj["prop"] to obj.prop.
// but ONLY if the string value is "safe" to be an identifier. Even though the ECMA-262
// spec says certain Unicode categories are okay, in practice the various major browsers
// all seem to have problems with certain characters in identifiers. Rather than risking
// some browsers breaking when we change this syntax, don't do it for those "danger" categories.
if (m_inBrackets && m_args != null)
{
// see if there is a single, constant argument
string argText = m_args.SingleConstantArgument;
if (argText != null)
{
// see if we want to replace the name
string newName;
if (Parser.Settings.HasRenamePairs && Parser.Settings.ManualRenamesProperties &&
Parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming) &&
!string.IsNullOrEmpty(newName = Parser.Settings.GetNewName(argText)))
{
// yes -- we are going to replace the name, either as a string literal, or by converting
// to a member-dot operation.
// See if we can't turn it into a dot-operator. If we can't, then we just want to replace the operator with
// a new constant wrapper. Otherwise we'll just replace the operator with a new constant wrapper.
if (Parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember) &&
JSScanner.IsSafeIdentifier(newName) &&
!JSScanner.IsKeyword(newName))
{
// the new name is safe to convert to a member-dot operator.
// but we don't want to convert the node to the NEW name, because we still need to Analyze the
// new member node -- and it might convert the new name to something else. So instead we're
// just going to convert this existing string to a member node WITH THE OLD STRING,
// and THEN analyze it (which will convert the old string to newName)
Member replacementMember = new Member(Context, Parser, m_func, argText);
Parent.ReplaceChild(this, replacementMember);
// this analyze call will convert the old-name member to the newName value
replacementMember.AnalyzeNode();
return;
}
else
{
// nope; can't convert to a dot-operator.
// we're just going to replace the first argument with a new string literal
// and continue along our merry way.
m_args.ReplaceChild(m_args[0], new ConstantWrapper(newName, PrimitiveType.String, m_args[0].Context, Parser));
}
}
else if (Parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember) &&
JSScanner.IsSafeIdentifier(argText) &&
!JSScanner.IsKeyword(argText))
{
// not a replacement, but the string literal is a safe identifier. So we will
// replace this call node with a Member-dot operation
Member replacementMember = new Member(Context, Parser, m_func, argText);
Parent.ReplaceChild(this, replacementMember);
replacementMember.AnalyzeNode();
return;
}
}
}
// call the base class to recurse
base.AnalyzeNode();
// call this AFTER recursing to give the fields a chance to resolve, because we only
// want to make this replacement if we are working on the global Date object.
if (!m_inBrackets && !m_isConstructor &&
(m_args == null || m_args.Count == 0) &&
member != null && string.CompareOrdinal(member.Name, "getTime") == 0 &&
Parser.Settings.IsModificationAllowed(TreeModifications.DateGetTimeToUnaryPlus))
{
// this is not a constructor and it's not a brackets call, and there are no arguments.
// if the function is a member operation to "getTime" and the object of the member is a
// constructor call to the global "Date" object (not a local), then we want to replace the call
// with a unary plus on the Date constructor. Converting to numeric type is the same as
// calling getTime, so it's the equivalent with much fewer bytes.
CallNode dateConstructor = member.Root as CallNode;
if (dateConstructor != null &&
dateConstructor.IsConstructor)
{
// lookup for the predifined (not local) "Date" field
Lookup lookup = dateConstructor.Function as Lookup;
if (lookup != null && string.CompareOrdinal(lookup.Name, "Date") == 0 &&
lookup.LocalField == null)
{
// this is in the pattern: (new Date()).getTime()
// we want to replace it with +new Date
// use the same date constructor node as the operand
NumericUnary unary = new NumericUnary(Context, Parser, dateConstructor, JSToken.Plus);
// replace us (the call to the getTime method) with this unary operator
Parent.ReplaceChild(this, unary);
// don't need to AnalyzeNode on the unary operator. The operand has already
// been analyzed when we recursed, and the unary operator wouldn't do anything
// special anyway (since the operand is not a numeric constant)
}
}
}
else if (Parser.Settings.EvalTreatment != EvalTreatment.Ignore)
{
// if this is a window.eval call, then we need to mark this scope as unknown just as
// we would if this was a regular eval call.
// (unless, of course, the parser settings say evals are safe)
// call AFTER recursing so we know the left-hand side properties have had a chance to
// lookup their fields to see if they are local or global
if (member != null && string.CompareOrdinal(member.Name, "eval") == 0)
{
if (member.LeftHandSide.IsWindowLookup)
{
// this is a call to window.eval()
// mark this scope as unknown so we don't crunch out locals
// we might reference in the eval at runtime
ScopeStack.Peek().IsKnownAtCompileTime = false;
}
}
else
{
CallNode callNode = m_func as CallNode;
if (callNode != null &&
callNode.InBrackets &&
callNode.LeftHandSide.IsWindowLookup &&
callNode.Arguments.IsSingleConstantArgument("eval"))
{
// this is a call to window["eval"]
// mark this scope as unknown so we don't crunch out locals
// we might reference in the eval at runtime
ScopeStack.Peek().IsKnownAtCompileTime = false;
}
}
}
/* REVIEW: may be too late. lookups may alread have been analyzed and
* found undefined
* // check to see if this is an assignment to a window["prop"] structure
* BinaryOperator binaryOp = Parent as BinaryOperator;
* if (binaryOp != null && binaryOp.IsAssign
* && m_inBrackets
* && m_func.IsWindowLookup
* && m_args != null)
* {
* // and IF the property is a non-empty constant that isn't currently
* // a global field...
* string propertyName = m_args.SingleConstantArgument;
* if (!string.IsNullOrEmpty(propertyName)
* && Parser.GlobalScope[propertyName] == null)
* {
* // we want to also add it to the global fields so it's not undefined
* Parser.GlobalScope.DeclareField(propertyName, null, 0);
* }
* }
*/
}
private ConstantWrapper LogicalOr(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
try
{
// if the left-hand side evaluates to true, return the left-hand side.
// if the left-hand side is false, return the right-hand side.
newLiteral = left.ToBoolean() ? left : right;
}
catch (InvalidCastException)
{
// if we couldn't cast to bool, ignore
}
}
return newLiteral;
}
protected virtual void CreateLiteralShortcuts()
{
if (m_literalMap != null)
{
// get a reference to the first function scope in the chain
// might be this, might be a parent
FunctionScope functionScope = null;
ActivationObject scope = this;
while (scope != null && (functionScope = scope as FunctionScope) == null)
{
scope = scope.Parent;
}
// if we didn't find a parent function scope, then don't do any combining
// because the literals are globals
if (functionScope != null)
{
// for each value in our literal map
foreach (string constantString in m_literalMap.Keys)
{
LiteralReference literalReference = m_literalMap[constantString];
// if the child scope isn't null, then we don't reference the literal
// and only one of our child scopes does, so we don't want to add the
// shortcut here.
// OR if there are no constant wrappers left in the list, then we've already
// replaced them all and there's nothing left to do.
// BUT if the child scope is null, either we reference it, or more than
// one child references it. So if there are any constant wrappers in the list,
// then we want to add the shortcut and replace all the constants
if (literalReference.ChildScope == null && literalReference.ConstantWrapperList.Count > 0)
{
// AND we only want to do it if it will be worthwhile.
// (and a constant of length 1 is never worthwhile)
int constantLength = constantString.Length;
if (constantLength > 1)
{
int minCount = (constantLength + 7) / (constantLength - 1);
if (literalReference.Count > minCount)
{
// create a special name that won't collide with any other variable names
string specialName = string.Format(CultureInfo.InvariantCulture, "[literal:{0}]", ++s_literalCounter);
// add a generated var statement at the top of the function block that
// is equal to the literal value (just use the first constant wrapper as a model)
ConstantWrapper modelConstant = literalReference.ConstantWrapperList[0];
// by default we will use the value of the first instance as the generated variable's value
object generatedValue = modelConstant.Value;
// BUT....
// if this is a numeric value, then we need to determine whether we should use a
// positive or negative version of this value to minimize the number of minus operators in the results
if (modelConstant.IsNumericLiteral)
{
// first we need to go through the existing references and count how many negative values there are
var numberOfNegatives = 0;
foreach (ConstantWrapper constantWrapper in literalReference.ConstantWrapperList)
{
// since the model us numeric, we shouldn't have any problems calling the
// ToNumber method on the others (which should all also be numeric)
if (constantWrapper.ToNumber() < 0)
{
++numberOfNegatives;
}
}
// now if more than half of the references are negative, we will want the generated value
// to also be negative! Otherwise we want to force it to Positive.
var absoluteValue = Math.Abs((double)generatedValue);
if (numberOfNegatives > literalReference.ConstantWrapperList.Count / 2)
{
// force it to negative
generatedValue = -absoluteValue;
}
else
{
// force it to positive
generatedValue = absoluteValue;
}
}
// add the generated variable to the function scope
functionScope.FunctionObject.AddGeneratedVar(
specialName,
new ConstantWrapper(
generatedValue,
modelConstant.PrimitiveType,
modelConstant.Context,
Parser),
true);
// walk the list of constant wrappers backwards (because we'll be removing them
// as we go along) and replace each one with a lookup for the generated variable.
// Don't forget to analyze the lookup.
for (int ndx = literalReference.ConstantWrapperList.Count - 1; ndx >= 0; --ndx)
{
ConstantWrapper constantWrapper = literalReference.ConstantWrapperList[ndx];
// create the lookup based on the thisliteral context
Lookup lookup = new Lookup(specialName, constantWrapper.Context, Parser);
// indicate this is generated by our code, not the user
lookup.IsGenerated = true;
// by default, we're just going to replace the constant with the lookup
AstNode replacement = lookup;
// if the constant wrapper is a numeric value that is the NEGATIVE of the
// combined numeric value (which would happen if the literal was subsequently
// combined with a unary minus operator), then we need to change this to a unary-minus
// operator on the lookup, not just the lookup.
if (constantWrapper.IsNumericLiteral)
{
// since the constant wrapper is numeric, we shouldn't have any problems
// calling ToNumber
if ((double)generatedValue == -constantWrapper.ToNumber())
{
// it has been negated! Change the replacement to a unary minus operator
// with the lookup as its operand
replacement = new NumericUnary(
constantWrapper.Context,
Parser,
lookup,
JSToken.Minus);
}
}
// replace the this literal with the appropriate node
constantWrapper.Parent.ReplaceChild(constantWrapper, replacement);
// set up the lookup's outer local field using the scope of the
// original constant wrapper
lookup.SetOuterLocalField(constantWrapper.EnclosingScope);
// and remove it from the list. This is so child scopes don't also try to
// add a shortcut -- the list will be empty.
literalReference.ConstantWrapperList.RemoveAt(ndx);
}
}
}
}
}
}
}
}
//---------------------------------------------------------------------------------------
// ParseIfStatement
//
// IfStatement :
// 'if' '(' Expression ')' Statement ElseStatement
//
// ElseStatement :
// <empty> |
// 'else' Statement
//---------------------------------------------------------------------------------------
private IfNode ParseIfStatement()
{
Context ifCtx = m_currentToken.Clone();
AstNode condition = null;
AstNode trueBranch = null;
AstNode falseBranch = null;
m_blockType.Add(BlockType.Block);
try
{
// parse condition
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
if (JSToken.LeftParenthesis != m_currentToken.Token)
ReportError(JSError.NoLeftParenthesis);
GetNextToken();
condition = ParseExpression();
// parse statements
if (JSToken.RightParenthesis != m_currentToken.Token)
{
ifCtx.UpdateWith(condition.Context);
ReportError(JSError.NoRightParenthesis);
}
else
ifCtx.UpdateWith(m_currentToken);
GetNextToken();
}
catch (RecoveryTokenException exc)
{
// make up an if condition
if (exc._partiallyComputedNode != null)
condition = exc._partiallyComputedNode;
else
condition = new ConstantWrapper(true, PrimitiveType.Boolean, CurrentPositionContext(), this);
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
exc._partiallyComputedNode = null; // really not much to pass up
// the if condition was so bogus we do not have a chance to make an If node, give up
throw;
}
else
{
if (exc._token == JSToken.RightParenthesis)
GetNextToken();
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
// if this is an assignment, throw a warning in case the developer
// meant to use == instead of =
// but no warning if the condition is wrapped in parens. We can know if it's wrapped in parens
// if the first character of the context is a paren and it's BEFORE the context of the leftmost
// context of the condition.
BinaryOperator binOp = condition as BinaryOperator;
if (binOp != null && binOp.OperatorToken == JSToken.Assign
&& condition.Context != null && condition.Context.Code != null
&& !(condition.Context.Code.StartsWith("(", StringComparison.Ordinal) && condition.Context.IsBefore(binOp.LeftHandSide.Context)))
{
condition.Context.HandleError(JSError.SuspectAssignment);
}
m_noSkipTokenSet.Add(NoSkipTokenSet.s_IfBodyNoSkipTokenSet);
if (JSToken.Semicolon == m_currentToken.Token)
{
ForceReportInfo(JSError.SuspectSemicolon);
}
else if (JSToken.LeftCurly != m_currentToken.Token)
{
// if the statements aren't withing curly-braces, throw a possible error
ReportError(JSError.StatementBlockExpected, ifCtx, true);
}
try
{
// parse a Statement, not a SourceElement
trueBranch = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
// make up a block for the if part
if (exc._partiallyComputedNode != null)
trueBranch = exc._partiallyComputedNode;
else
trueBranch = new Block(CurrentPositionContext(), this);
if (IndexOfToken(NoSkipTokenSet.s_IfBodyNoSkipTokenSet, exc) == -1)
{
// we have to pass the exception to someone else, make as much as you can from the if
exc._partiallyComputedNode = new IfNode(ifCtx, this, condition, trueBranch, falseBranch);
throw;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_IfBodyNoSkipTokenSet);
}
// parse else, if any
if (JSToken.Else == m_currentToken.Token)
{
Context elseCtx = m_currentToken.Clone();
GetNextToken();
if (JSToken.Semicolon == m_currentToken.Token)
ForceReportInfo(JSError.SuspectSemicolon);
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token
&& JSToken.If != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, elseCtx, true);
}
try
{
// parse a Statement, not a SourceElement
falseBranch = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
// make up a block for the else part
if (exc._partiallyComputedNode != null)
falseBranch = exc._partiallyComputedNode;
else
falseBranch = new Block(CurrentPositionContext(), this);
exc._partiallyComputedNode = new IfNode(ifCtx, this, condition, trueBranch, falseBranch);
throw;
}
}
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return new IfNode(ifCtx, this, condition, trueBranch, falseBranch);
}
/// <summary>
/// Evaluate: CONST [op] (CONST [op] OTHER)
/// </summary>
/// <param name="thisConstant">first constant</param>
/// <param name="otherConstant">second constant</param>
/// <param name="leftOperator">second operator</param>
private void EvalToTheRight(BinaryOperator node, ConstantWrapper thisConstant, ConstantWrapper otherConstant, BinaryOperator rightOperator)
{
if (node.OperatorToken == JSToken.Plus)
{
if (rightOperator.OperatorToken == JSToken.Plus && otherConstant.IsStringLiteral)
{
// plus-plus, and the other constant is a string. So the right operator will be a string-concat
// that generates a string. And since this is a plus-operator, then this operator will be a string-
// concat as well. So we can just combine the strings now and replace our node with the right-hand
// operation
ConstantWrapper newLiteral = StringConcat(thisConstant, otherConstant);
if (newLiteral != null)
{
RotateFromRight(node, rightOperator, newLiteral);
}
}
else if (rightOperator.OperatorToken == JSToken.Minus && !thisConstant.IsStringLiteral)
{
// plus-minus. Now, the minus operation happens first, and it will perform a numeric
// operation. The plus is NOT string, so that means it will also be a numeric operation
// and we can combine the operators numericly.
ConstantWrapper newLiteral = NumericAddition(thisConstant, otherConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
RotateFromRight(node, rightOperator, newLiteral);
}
else
{
ConstantWrapper rightRight = rightOperator.Operand2 as ConstantWrapper;
if (rightRight != null)
{
EvalFarToTheRight(node, thisConstant, rightRight, rightOperator);
}
}
}
}
else if (node.OperatorToken == JSToken.Minus && rightOperator.OperatorToken == JSToken.Minus)
{
// minus-minus
// both operations are numeric, so we can combine the constant operands. However, we
// can't combine them into a plus, so make sure we do the minus in the opposite direction
ConstantWrapper newLiteral = Minus(otherConstant, thisConstant);
if (newLiteral != null && NoOverflow(newLiteral))
{
rightOperator.SwapOperands();
RotateFromLeft(node, rightOperator, newLiteral);
}
else
{
ConstantWrapper rightRight = rightOperator.Operand2 as ConstantWrapper;
if (rightRight != null)
{
EvalFarToTheRight(node, thisConstant, rightRight, rightOperator);
}
}
}
else if (node.OperatorToken == JSToken.Multiply
&& (rightOperator.OperatorToken == JSToken.Multiply || rightOperator.OperatorToken == JSToken.Divide))
{
// multiply-divide or multiply-multiply
// multiply the operands and use the right-hand operator
ConstantWrapper newLiteral = Multiply(thisConstant, otherConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, newLiteral))
{
RotateFromRight(node, rightOperator, newLiteral);
}
}
else if (node.OperatorToken == JSToken.Divide)
{
if (rightOperator.OperatorToken == JSToken.Multiply)
{
// divide-multiply
ConstantWrapper newLiteral = Divide(thisConstant, otherConstant);
if (newLiteral != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, newLiteral)
&& newLiteral.ToCode().Length < thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// flip the operator: multiply becomes divide; devide becomes multiply
rightOperator.OperatorToken = JSToken.Divide;
RotateFromRight(node, rightOperator, newLiteral);
}
}
else if (rightOperator.OperatorToken == JSToken.Divide)
{
// divide-divide
// get constants for left/right and for right/left
ConstantWrapper leftOverRight = Divide(thisConstant, otherConstant);
ConstantWrapper rightOverLeft = Divide(otherConstant, thisConstant);
// get the lengths of the resulting code
int leftOverRightLength = leftOverRight != null ? leftOverRight.ToCode().Length : int.MaxValue;
int rightOverLeftLength = rightOverLeft != null ? rightOverLeft.ToCode().Length : int.MaxValue;
// try whichever is smaller
if (leftOverRight != null && NoMultiplicativeOverOrUnderFlow(thisConstant, otherConstant, leftOverRight)
&& (rightOverLeft == null || leftOverRightLength < rightOverLeftLength))
{
// use left-over-right.
// but only if the resulting value is smaller than the original expression
if (leftOverRightLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// We don't need to swap the operands, but we do need to switch the operator
rightOperator.OperatorToken = JSToken.Multiply;
RotateFromRight(node, rightOperator, leftOverRight);
}
}
else if (rightOverLeft != null && NoMultiplicativeOverOrUnderFlow(otherConstant, thisConstant, rightOverLeft))
{
// but only if the resulting value is smaller than the original expression
if (rightOverLeftLength <= thisConstant.ToCode().Length + otherConstant.ToCode().Length + 1)
{
// use right-over-left. Keep the operator, but swap the operands
rightOperator.SwapOperands();
RotateFromLeft(node, rightOperator, rightOverLeft);
}
}
}
}
}
//---------------------------------------------------------------------------------------
// ParseForStatement
//
// ForStatement :
// 'for' '(' OptionalExpressionNoIn ';' OptionalExpression ';' OptionalExpression ')'
// 'for' '(' 'var' VariableDeclarationListNoIn ';' OptionalExpression ';' OptionalExpression ')'
// 'for' '(' LeftHandSideExpression 'in' Expression')'
// 'for' '(' 'var' Identifier OptionalInitializerNoIn 'in' Expression')'
//
// OptionalExpressionNoIn :
// <empty> |
// ExpressionNoIn // same as Expression but does not process 'in' as an operator
//
// OptionalInitializerNoIn :
// <empty> |
// InitializerNoIn // same as initializer but does not process 'in' as an operator
//---------------------------------------------------------------------------------------
private AstNode ParseForStatement()
{
m_blockType.Add(BlockType.Loop);
AstNode forNode = null;
try
{
Context forCtx = m_currentToken.Clone();
GetNextToken();
if (JSToken.LeftParenthesis != m_currentToken.Token)
ReportError(JSError.NoLeftParenthesis);
GetNextToken();
bool isForIn = false, recoveryInForIn = false;
AstNode lhs = null, initializer = null, condOrColl = null, increment = null;
try
{
if (JSToken.Var == m_currentToken.Token)
{
isForIn = true;
Var varList = new Var(m_currentToken.Clone(), this);
varList.Append(ParseIdentifierInitializer(JSToken.In, (FieldAttributes)0));
// a list of variable initializers is allowed only in a for(;;)
while (JSToken.Comma == m_currentToken.Token)
{
isForIn = false;
varList.Append(ParseIdentifierInitializer(JSToken.In, (FieldAttributes)0));
//initializer = new Comma(initializer.context.CombineWith(var.context), initializer, var);
}
initializer = varList;
// if it could still be a for..in, now it's time to get the 'in'
if (isForIn)
{
if (JSToken.In == m_currentToken.Token)
{
GetNextToken();
condOrColl = ParseExpression();
}
else
isForIn = false;
}
}
else
{
if (JSToken.Semicolon != m_currentToken.Token)
{
bool isLHS;
initializer = ParseUnaryExpression(out isLHS, false);
if (isLHS && JSToken.In == m_currentToken.Token)
{
isForIn = true;
lhs = initializer;
initializer = null;
GetNextToken();
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
condOrColl = ParseExpression();
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
exc._partiallyComputedNode = null;
throw;
}
else
{
if (exc._partiallyComputedNode == null)
condOrColl = new ConstantWrapper(true, PrimitiveType.Boolean, CurrentPositionContext(), this); // what could we put here?
else
condOrColl = exc._partiallyComputedNode;
}
if (exc._token == JSToken.RightParenthesis)
{
GetNextToken();
recoveryInForIn = true;
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
}
else
initializer = ParseExpression(initializer, false, isLHS, JSToken.In);
}
}
}
catch (RecoveryTokenException exc)
{
// error is too early abort for
exc._partiallyComputedNode = null;
throw;
}
// at this point we know whether or not is a for..in
if (isForIn)
{
if (!recoveryInForIn)
{
if (JSToken.RightParenthesis != m_currentToken.Token)
ReportError(JSError.NoRightParenthesis);
forCtx.UpdateWith(m_currentToken);
GetNextToken();
}
AstNode body = null;
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, forCtx, true);
}
try
{
// parse a Statement, not a SourceElement
body = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode == null)
body = new Block(CurrentPositionContext(), this);
else
body = exc._partiallyComputedNode;
exc._partiallyComputedNode = new ForIn(forCtx, this, (lhs != null ? lhs : initializer), condOrColl, body);
throw;
}
// for (a in b)
// lhs = a, initializer = null
// for (var a in b)
// lhs = null, initializer = var a
forNode = new ForIn(forCtx, this, (lhs != null ? lhs : initializer), condOrColl, body);
}
else
{
m_noSkipTokenSet.Add(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
try
{
if (JSToken.Semicolon != m_currentToken.Token)
{
ReportError(JSError.NoSemicolon);
if (JSToken.Colon == m_currentToken.Token)
{
m_noSkipTokenSet.Add(NoSkipTokenSet.s_VariableDeclNoSkipTokenSet);
try
{
SkipTokensAndThrow();
}
catch (RecoveryTokenException)
{
if (JSToken.Semicolon == m_currentToken.Token)
m_errorToken = null;
else
throw;
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_VariableDeclNoSkipTokenSet);
}
}
}
GetNextToken();
if (JSToken.Semicolon != m_currentToken.Token)
{
condOrColl = ParseExpression();
if (JSToken.Semicolon != m_currentToken.Token)
ReportError(JSError.NoSemicolon);
}
GetNextToken();
if (JSToken.RightParenthesis != m_currentToken.Token)
increment = ParseExpression();
if (JSToken.RightParenthesis != m_currentToken.Token)
ReportError(JSError.NoRightParenthesis);
forCtx.UpdateWith(m_currentToken);
GetNextToken();
}
catch (RecoveryTokenException exc)
{
if (IndexOfToken(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet, exc) == -1)
{
exc._partiallyComputedNode = null;
throw;
}
else
{
// discard any partial info, just genrate empty condition and increment and keep going
exc._partiallyComputedNode = null;
if (condOrColl == null)
condOrColl = new ConstantWrapper(true, PrimitiveType.Boolean, CurrentPositionContext(), this);
}
if (exc._token == JSToken.RightParenthesis)
{
GetNextToken();
}
}
finally
{
m_noSkipTokenSet.Remove(NoSkipTokenSet.s_BlockConditionNoSkipTokenSet);
}
AstNode body = null;
// if the statements aren't withing curly-braces, throw a possible error
if (JSToken.LeftCurly != m_currentToken.Token)
{
ReportError(JSError.StatementBlockExpected, forCtx, true);
}
try
{
// parse a Statement, not a SourceElement
body = ParseStatement(false);
}
catch (RecoveryTokenException exc)
{
if (exc._partiallyComputedNode == null)
body = new Block(CurrentPositionContext(), this);
else
body = exc._partiallyComputedNode;
exc._partiallyComputedNode = new ForNode(forCtx, this, initializer, condOrColl, increment, body);
throw;
}
forNode = new ForNode(forCtx, this, initializer, condOrColl, increment, body);
}
}
finally
{
m_blockType.RemoveAt(m_blockType.Count - 1);
}
return forNode;
}
public override void Visit(Member node)
{
if (node != null)
{
// if we don't even have any resource strings, then there's nothing
// we need to do and we can just perform the base operation
ResourceStrings resourceStrings = m_parser.ResourceStrings;
if (resourceStrings != null && resourceStrings.Count > 0)
{
// see if the root object is a lookup that corresponds to the
// global value (not a local field) for our resource object
// (same name)
Lookup rootLookup = node.Root as Lookup;
if (rootLookup != null
&& rootLookup.LocalField == null
&& string.CompareOrdinal(rootLookup.Name, resourceStrings.Name) == 0)
{
// it is -- we're going to replace this with a string value.
// if this member name is a string on the object, we'll replacve it with
// the literal. Otherwise we'll replace it with an empty string.
// see if the string resource contains this value
ConstantWrapper stringLiteral = new ConstantWrapper(
resourceStrings[node.Name] ?? string.Empty,
PrimitiveType.String,
node.Context,
m_parser
);
node.Parent.ReplaceChild(node, stringLiteral);
// analyze the literal
stringLiteral.Accept(this);
return;
}
}
// if we are replacing property names and we have something to replace
if (m_parser.Settings.HasRenamePairs && m_parser.Settings.ManualRenamesProperties
&& m_parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming))
{
// see if this name is a target for replacement
string newName = m_parser.Settings.GetNewName(node.Name);
if (!string.IsNullOrEmpty(newName))
{
// it is -- set the name to the new name
node.Name = newName;
}
}
// check the name of the member for reserved words that aren't allowed
if (JSScanner.IsKeyword(node.Name, ScopeStack.Peek().UseStrict))
{
node.NameContext.HandleError(JSError.KeywordUsedAsIdentifier, true);
}
// recurse
base.Visit(node);
}
}
private ConstantWrapper BitwiseXor(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
try
{
Int32 lValue = left.ToInt32();
Int32 rValue = right.ToInt32();
newLiteral = new ConstantWrapper(Convert.ToDouble(lValue ^ rValue), PrimitiveType.Number, null, m_parser);
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
return newLiteral;
}
public void Visit(ConstantWrapper node)
{
// it's a constant, so we don't care
}
public override void Visit(CallNode node)
{
if (node != null)
{
// see if this is a member (we'll need it for a couple checks)
Member member = node.Function as Member;
if (m_parser.Settings.StripDebugStatements
&& m_parser.Settings.IsModificationAllowed(TreeModifications.StripDebugStatements))
{
// if this is a member, and it's a debugger object, and it's a constructor....
if (member != null && member.IsDebuggerStatement && node.IsConstructor)
{
// we need to replace our debugger object with a generic Object
node.ReplaceChild(node.Function, new Lookup("Object", node.Function.Context, m_parser));
// and make sure the node list is empty
if (node.Arguments != null && node.Arguments.Count > 0)
{
node.ReplaceChild(node.Arguments, new AstNodeList(node.Arguments.Context, m_parser));
}
}
}
// if this is a constructor and we want to collapse
// some of them to literals...
if (node.IsConstructor && m_parser.Settings.CollapseToLiteral)
{
// see if this is a lookup, and if so, if it's pointing to one
// of the two constructors we want to collapse
Lookup lookup = node.Function as Lookup;
if (lookup != null)
{
if (lookup.Name == "Object"
&& m_parser.Settings.IsModificationAllowed(TreeModifications.NewObjectToObjectLiteral))
{
// no arguments -- the Object constructor with no arguments is the exact same as an empty
// object literal
if (node.Arguments == null || node.Arguments.Count == 0)
{
// replace our node with an object literal
ObjectLiteral objLiteral = new ObjectLiteral(node.Context, m_parser, null, null);
if (node.Parent.ReplaceChild(node, objLiteral))
{
// and bail now. No need to recurse -- it's an empty literal
return;
}
}
else if (node.Arguments.Count == 1)
{
// one argument
// check to see if it's an object literal.
ObjectLiteral objectLiteral = node.Arguments[0] as ObjectLiteral;
if (objectLiteral != null)
{
// the Object constructor with an argument that is a JavaScript object merely returns the
// argument. Since the argument is an object literal, it is by definition a JavaScript object
// and therefore we can replace the constructor call with the object literal
node.Parent.ReplaceChild(node, objectLiteral);
// don't forget to recurse the object now
objectLiteral.Accept(this);
// and then bail -- we don't want to process this call
// operation any more; we've gotten rid of it
return;
}
}
}
else if (lookup.Name == "Array"
&& m_parser.Settings.IsModificationAllowed(TreeModifications.NewArrayToArrayLiteral))
{
// Array is trickier.
// If there are no arguments, then just use [].
// if there are multiple arguments, then use [arg0,arg1...argN].
// but if there is one argument and it's numeric, we can't crunch it.
// also can't crunch if it's a function call or a member or something, since we won't
// KNOW whether or not it's numeric.
//
// so first see if it even is a single-argument constant wrapper.
ConstantWrapper constWrapper = (node.Arguments != null && node.Arguments.Count == 1
? node.Arguments[0] as ConstantWrapper
: null);
// if the argument count is not one, then we crunch.
// if the argument count IS one, we only crunch if we have a constant wrapper,
// AND it's not numeric.
if (node.Arguments == null
|| node.Arguments.Count != 1
|| (constWrapper != null && !constWrapper.IsNumericLiteral))
{
// create the new array literal object
ArrayLiteral arrayLiteral = new ArrayLiteral(node.Context, m_parser, node.Arguments);
// replace ourself within our parent
if (node.Parent.ReplaceChild(node, arrayLiteral))
{
// recurse
arrayLiteral.Accept(this);
// and bail -- we don't want to recurse this node any more
return;
}
}
}
}
}
// if we are replacing resource references with strings generated from resource files
// and this is a brackets call: lookup[args]
ResourceStrings resourceStrings = m_parser.ResourceStrings;
if (node.InBrackets && resourceStrings != null && resourceStrings.Count > 0)
{
// see if the root object is a lookup that corresponds to the
// global value (not a local field) for our resource object
// (same name)
Lookup rootLookup = node.Function as Lookup;
if (rootLookup != null
&& rootLookup.LocalField == null
&& string.CompareOrdinal(rootLookup.Name, resourceStrings.Name) == 0)
{
// we're going to replace this node with a string constant wrapper
// but first we need to make sure that this is a valid lookup.
// if the parameter contains anything that would vary at run-time,
// then we need to throw an error.
// the parser will always have either one or zero nodes in the arguments
// arg list. We're not interested in zero args, so just make sure there is one
if (node.Arguments.Count == 1)
{
// must be a constant wrapper
ConstantWrapper argConstant = node.Arguments[0] as ConstantWrapper;
if (argConstant != null)
{
string resourceName = argConstant.Value.ToString();
// get the localized string from the resources object
ConstantWrapper resourceLiteral = new ConstantWrapper(
resourceStrings[resourceName],
PrimitiveType.String,
node.Context,
m_parser);
// replace this node with localized string, analyze it, and bail
// so we don't anaylze the tree we just replaced
node.Parent.ReplaceChild(node, resourceLiteral);
resourceLiteral.Accept(this);
return;
}
else
{
// error! must be a constant
node.Context.HandleError(
JSError.ResourceReferenceMustBeConstant,
true);
}
}
else
{
// error! can only be a single constant argument to the string resource object.
// the parser will only have zero or one arguments, so this must be zero
// (since the parser won't pass multiple args to a [] operator)
node.Context.HandleError(
JSError.ResourceReferenceMustBeConstant,
true);
}
}
}
// and finally, if this is a backets call and the argument is a constantwrapper that can
// be an identifier, just change us to a member node: obj["prop"] to obj.prop.
// but ONLY if the string value is "safe" to be an identifier. Even though the ECMA-262
// spec says certain Unicode categories are okay, in practice the various major browsers
// all seem to have problems with certain characters in identifiers. Rather than risking
// some browsers breaking when we change this syntax, don't do it for those "danger" categories.
if (node.InBrackets && node.Arguments != null)
{
// see if there is a single, constant argument
string argText = node.Arguments.SingleConstantArgument;
if (argText != null)
{
// see if we want to replace the name
string newName;
if (m_parser.Settings.HasRenamePairs && m_parser.Settings.ManualRenamesProperties
&& m_parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming)
&& !string.IsNullOrEmpty(newName = m_parser.Settings.GetNewName(argText)))
{
// yes -- we are going to replace the name, either as a string literal, or by converting
// to a member-dot operation.
// See if we can't turn it into a dot-operator. If we can't, then we just want to replace the operator with
// a new constant wrapper. Otherwise we'll just replace the operator with a new constant wrapper.
if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember)
&& JSScanner.IsSafeIdentifier(newName)
&& !JSScanner.IsKeyword(newName, node.EnclosingScope.UseStrict))
{
// the new name is safe to convert to a member-dot operator.
// but we don't want to convert the node to the NEW name, because we still need to Analyze the
// new member node -- and it might convert the new name to something else. So instead we're
// just going to convert this existing string to a member node WITH THE OLD STRING,
// and THEN analyze it (which will convert the old string to newName)
Member replacementMember = new Member(node.Context, m_parser, node.Function, argText, node.Arguments[0].Context);
node.Parent.ReplaceChild(node, replacementMember);
// this analyze call will convert the old-name member to the newName value
replacementMember.Accept(this);
return;
}
else
{
// nope; can't convert to a dot-operator.
// we're just going to replace the first argument with a new string literal
// and continue along our merry way.
node.Arguments.ReplaceChild(node.Arguments[0], new ConstantWrapper(newName, PrimitiveType.String, node.Arguments[0].Context, m_parser));
}
}
else if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember)
&& JSScanner.IsSafeIdentifier(argText)
&& !JSScanner.IsKeyword(argText, node.EnclosingScope.UseStrict))
{
// not a replacement, but the string literal is a safe identifier. So we will
// replace this call node with a Member-dot operation
Member replacementMember = new Member(node.Context, m_parser, node.Function, argText, node.Arguments[0].Context);
node.Parent.ReplaceChild(node, replacementMember);
replacementMember.Accept(this);
return;
}
}
}
// call the base class to recurse
base.Visit(node);
// might have changed
member = node.Function as Member;
// call this AFTER recursing to give the fields a chance to resolve, because we only
// want to make this replacement if we are working on the global Date object.
if (!node.InBrackets && !node.IsConstructor
&& (node.Arguments == null || node.Arguments.Count == 0)
&& member != null && string.CompareOrdinal(member.Name, "getTime") == 0
&& m_parser.Settings.IsModificationAllowed(TreeModifications.DateGetTimeToUnaryPlus))
{
// this is not a constructor and it's not a brackets call, and there are no arguments.
// if the function is a member operation to "getTime" and the object of the member is a
// constructor call to the global "Date" object (not a local), then we want to replace the call
// with a unary plus on the Date constructor. Converting to numeric type is the same as
// calling getTime, so it's the equivalent with much fewer bytes.
CallNode dateConstructor = member.Root as CallNode;
if (dateConstructor != null
&& dateConstructor.IsConstructor)
{
// lookup for the predifined (not local) "Date" field
Lookup lookup = dateConstructor.Function as Lookup;
if (lookup != null && string.CompareOrdinal(lookup.Name, "Date") == 0
&& lookup.LocalField == null)
{
// this is in the pattern: (new Date()).getTime()
// we want to replace it with +new Date
// use the same date constructor node as the operand
NumericUnary unary = new NumericUnary(node.Context, m_parser, dateConstructor, JSToken.Plus);
// replace us (the call to the getTime method) with this unary operator
node.Parent.ReplaceChild(node, unary);
// don't need to recurse on the unary operator. The operand has already
// been analyzed when we recursed, and the unary operator wouldn't do anything
// special anyway (since the operand is not a numeric constant)
}
}
}
else
{
var isEval = false;
var lookup = node.Function as Lookup;
if (lookup != null
&& string.CompareOrdinal(lookup.Name, "eval") == 0
&& lookup.VariableField is JSPredefinedField)
{
// call to predefined eval function
isEval = true;
}
else if (member != null && string.CompareOrdinal(member.Name, "eval") == 0)
{
// if this is a window.eval call, then we need to mark this scope as unknown just as
// we would if this was a regular eval call.
// (unless, of course, the parser settings say evals are safe)
// call AFTER recursing so we know the left-hand side properties have had a chance to
// lookup their fields to see if they are local or global
if (member.LeftHandSide.IsWindowLookup)
{
// this is a call to window.eval()
isEval = true;
}
}
else
{
CallNode callNode = node.Function as CallNode;
if (callNode != null
&& callNode.InBrackets
&& callNode.LeftHandSide.IsWindowLookup
&& callNode.Arguments.IsSingleConstantArgument("eval"))
{
// this is a call to window["eval"]
isEval = true;
}
}
if (isEval)
{
if (m_parser.Settings.EvalTreatment != EvalTreatment.Ignore)
{
// mark this scope as unknown so we don't crunch out locals
// we might reference in the eval at runtime
ScopeStack.Peek().IsKnownAtCompileTime = false;
}
}
}
}
}
