public String ReadName()
{
if (_scopeStack.Count == 0)
{
throw new Exception("Cannot read a name when there is no scope.");
}
Scope scope = _scopeStack.Peek();
if (scope.ScopeType != JsonReader.ScopeType.Object)
{
throw new Exception("Cannot read a name when the scope is not an object.");
}
if (scope.NameRead)
{
throw new Exception("Cannot read a name when one has already been read.");
}
String result = ParseString();
scope.NameRead = true;
if (_c != ':')
{
throw new Exception("Expected ':'.");
}
_c = (char)_reader.Read();
ParseWhiteSpace();
return(result);
}
public Unit VisitVariable(Expr.Variable expr)
{
// Because we recurse into the initializer expression (while the scope has the variable)
// in 'NotReady'), we can use this to check that the initializer expression doesn't refer
// to this variable.
Resolution res;
if (_scopes.Count != 0 && _scopes.Peek().TryGetValue(expr.Name.Lexeme, out res) && res == Resolution.NotReady)
{
_errors.AddResolverError(expr.Name, "Cannot read local variable in its own initializer");
}
ResolveLocal(expr, expr.Name);
return(Unit.Default);
}
internal override void AnalyzeNode()
{
// we're going to look for the first FunctionScope on the stack
FunctionScope functionScope = null;
// get the current scope
ActivationObject activationObject = ScopeStack.Peek();
do
{
functionScope = activationObject as FunctionScope;
if (functionScope != null)
{
// found it -- break out of the loop
break;
}
// otherwise go up the chain
activationObject = activationObject.Parent;
} while (activationObject != null);
// if we found one....
if (functionScope != null)
{
// add this object to the list of thisliterals
functionScope.AddThisLiteral(this);
}
}
public void Dispose()
{
if (ScopeStack.Peek() != this)
{
throw new InvalidOperationException("Parent logging scope is being disposed before child scope.");
}
ScopeStack = ScopeStack.Pop();
RebuildCurrent();
}
/// <summary>
/// Writes the start of an object
/// </summary>
public JsonWriter WriteStartObject()
{
if (_scopeStack.Count > 0)
{
Scope scope = _scopeStack.Peek();
if ((scope.ScopeType == ScopeType.Object) && (!scope.NameWritten))
{
throw new Exception("Must write a name before creating a nested object.");
}
// When writing an array of objects we separate them with commas
WriteComma();
}
_scopeStack.Push(new Scope(ScopeType.Object));
_writer.Write('{');
return(this);
}
internal void Eval(char symbol)
{
var currentScopeBeforeEval = ScopeStack.Peek();
var resultingState = currentScopeBeforeEval.State.Eval(symbol.ToString());
var currentScopeAfterEval = ScopeStack.Peek();
// Only update the state is we still are in the same scope as before the Eval.
// Without this check, we might alter state on the parent scope when the child scope's state changes
if (currentScopeAfterEval == currentScopeBeforeEval)
{
currentScopeAfterEval.State = resultingState;
}
}
internal override void AnalyzeNode()
{
// if the developer hasn't explicitly flagged eval statements as safe...
if (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
ActivationObject enclosingScope = ScopeStack.Peek();
if (enclosingScope != null)
{
enclosingScope.IsKnownAtCompileTime = false;
}
}
// then just do the default analysis
base.AnalyzeNode();
}
internal override void AnalyzeNode()
{
// first we want to make sure that we are indeed within a function scope.
// it makes no sense to have a return outside of a function
ActivationObject scope = ScopeStack.Peek();
while (scope != null && !(scope is FunctionScope))
{
scope = scope.Parent;
}
if (scope == null)
{
Context.HandleError(JSError.BadReturn);
}
// now just do the default analyze
base.AnalyzeNode();
}
public override Node Visit(VariableReferenceExpression variableRef)
{
((ScopeDeclarationWithRef)ScopeStack.Peek()).VariableReferences.Add(variableRef);
return(variableRef);
}
protected void Visit(VariableReferenceExpression variableRef)
{
((ScopeDeclarationWithRef)ScopeStack.Peek()).VariableReferences.Add(variableRef);
}
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);
* }
* }
*/
}
internal static bool IsCurrentLoggingScope(LoggingScope scope) => !ScopeStack.IsEmpty && ScopeStack.Peek().LoggingScope == scope;
public VariableDeclaration(Context context, JSParser parser, string identifier, Context idContext, AstNode initializer, FieldAttributes fieldAttributes, bool ignoreDuplicates)
: base(context, parser)
{
// identifier cannot be null
m_identifier = identifier;
// initializer may be null
m_initializer = initializer;
if (m_initializer != null)
{
m_initializer.Parent = this;
}
// we'll need to do special stuff if the initializer if a function expression,
// so try the conversion now
FunctionObject functionValue = m_initializer as FunctionObject;
string name = m_identifier.ToString();
ActivationObject currentScope = ScopeStack.Peek();
ActivationObject definingScope = currentScope;
if (definingScope is BlockScope)
{
// block scope -- the variable is ACTUALLY defined in the containing function/global scope,
// so we need to check THERE for duplicate defines.
do
{
definingScope = definingScope.Parent;
} while (definingScope is BlockScope);
}
JSVariableField field = definingScope[name];
if (field != null &&
(functionValue == null || functionValue != field.FieldValue))
{
// this is a declaration that already has a field declared.
// if the field is a named function expression, we want to fire an
// ambiguous named function expression error -- and we know it's an NFE
// if the FieldValue is a function object OR if the field
// has already been marked ambiguous
if (field.IsAmbiguous || field.FieldValue is FunctionObject)
{
if (idContext != null)
{
idContext.HandleError(
JSError.AmbiguousNamedFunctionExpression,
true
);
}
else if (context != null)
{
// not identifier context???? Try the whole statment context.
// if neither context is set, then we don't get an error!
context.HandleError(
JSError.AmbiguousNamedFunctionExpression,
true
);
}
// if we are preserving function names, then we need to mark this field
// as not crunchable
if (Parser.Settings.PreserveFunctionNames)
{
field.CanCrunch = false;
}
}
else if (!ignoreDuplicates)
{
if (idContext != null)
{
// otherwise just a normal duplicate error
idContext.HandleError(
JSError.DuplicateName,
field.IsLiteral
);
}
else if (context != null)
{
// otherwise just a normal duplicate error
context.HandleError(
JSError.DuplicateName,
field.IsLiteral
);
}
}
}
bool isLiteral = ((fieldAttributes & FieldAttributes.Literal) != 0);
// normally the value will be null.
// but if there is no initializer, we'll use Missing so we can tell the difference.
// and if this is a literal, we'll set it to the actual literal astnode
object val = null;
if (m_initializer == null)
{
val = Missing.Value;
}
else if (isLiteral || (functionValue != null))
{
val = m_initializer;
}
m_field = currentScope.DeclareField(
m_identifier,
val,
fieldAttributes
);
m_field.OriginalContext = idContext;
// we are now declared by a var statement
m_field.IsDeclared = true;
// if we are declaring a variable inside a with statement, then we will be declaring
// a local variable in the enclosing scope if the with object doesn't have a property
// of that name. But if it does, we won't actually be creating a variable field -- we'll
// just use the property. So if we use an initializer in this declaration, then we will
// actually be referencing the value.
// SO, if this is a with-scope and this variable declaration has an initializer, we're going
// to go ahead and bump up the reference.
if (currentScope is WithScope && m_initializer != null)
{
m_field.AddReference(currentScope);
}
// special case the ambiguous function expression test. If we are var-ing a variable
// with the same name as the function expression, then it's okay. We won't have an ambiguous
// reference and it will be okay to use the name to reference the function expression
if (functionValue != null && string.CompareOrdinal(m_identifier, functionValue.Name) == 0)
{
// null out the link to the named function expression
// and make the function object point to the PROPER variable: the local within its own scope
// and the inner is not pointing to the outer.
functionValue.DetachFromOuterField(false);
m_field.IsFunction = false;
}
}
internal override void AnalyzeNode()
{
// figure out if our reference type is a function or a constructor
if (Parent is CallNode)
{
m_refType = (
((CallNode)Parent).IsConstructor
? ReferenceType.Constructor
: ReferenceType.Function
);
}
ActivationObject scope = ScopeStack.Peek();
VariableField = scope.FindReference(m_name);
if (VariableField == null)
{
// this must be a global. if it isn't in the global space, throw an error
// this name is not in the global space.
// if it isn't generated, then we want to throw an error
// we also don't want to report an undefined variable if it is the object
// of a typeof operator
if (!m_isGenerated && !(Parent is TypeOfNode))
{
// report this undefined reference
Context.ReportUndefined(this);
// possibly undefined global (but definitely not local)
Context.HandleError(
(Parent is CallNode && ((CallNode)Parent).Function == this ? JSError.UndeclaredFunction : JSError.UndeclaredVariable),
null,
false
);
}
if (!(scope is GlobalScope))
{
// add it to the scope so we know this scope references the global
scope.AddField(new JSGlobalField(
m_name,
Missing.Value,
0
));
}
}
else
{
// BUT if this field is a place-holder in the containing scope of a named
// function expression, then we need to throw an ambiguous named function expression
// error because this could cause problems.
// OR if the field is already marked as ambiguous, throw the error
if (VariableField.NamedFunctionExpression != null ||
VariableField.IsAmbiguous)
{
// mark it as a field that's referenced ambiguously
VariableField.IsAmbiguous = true;
// throw as an error
Context.HandleError(JSError.AmbiguousNamedFunctionExpression, true);
// if we are preserving function names, then we need to mark this field
// as not crunchable
if (Parser.Settings.PreserveFunctionNames)
{
VariableField.CanCrunch = false;
}
}
// see if this scope already points to this name
if (scope[m_name] == null)
{
// create an inner reference so we don't keep walking up the scope chain for this name
VariableField = scope.CreateInnerField(VariableField);
}
// add the reference
VariableField.AddReference(scope);
if (VariableField is JSPredefinedField)
{
// this is a predefined field. If it's Nan or Infinity, we should
// replace it with the numeric value in case we need to later combine
// some literal expressions.
if (string.CompareOrdinal(m_name, "NaN") == 0)
{
// don't analyze the new ConstantWrapper -- we don't want it to take part in the
// duplicate constant combination logic should it be turned on.
Parent.ReplaceChild(this, new ConstantWrapper(double.NaN, PrimitiveType.Number, Context, Parser));
}
else if (string.CompareOrdinal(m_name, "Infinity") == 0)
{
// don't analyze the new ConstantWrapper -- we don't want it to take part in the
// duplicate constant combination logic should it be turned on.
Parent.ReplaceChild(this, new ConstantWrapper(double.PositiveInfinity, PrimitiveType.Number, Context, Parser));
}
}
}
}
