private static void ResolveLookups(JsActivationObject scope, JsSettings settings)
{
// resolve each lookup this scope contains
foreach (var lookup in scope.ScopeLookups)
{
ResolveLookup(scope, lookup, settings);
}
// and recurse
foreach (var childScope in scope.ChildScopes)
{
ResolveLookups(childScope, settings);
}
// mark any variables defined in this scope that don't have any references
// so we can throw warnings later. We can't rely on the reference count because
// we might remove references while optimizing code -- if we throw an error when
// the count gets to zero, then we would be reporting errors that don't exist.
// but we DO know right now what isn't referenced at all.
foreach (var field in scope.NameTable.Values)
{
if (field.RefCount == 0)
{
field.HasNoReferences = true;
}
}
}
protected JsActivationObject(JsActivationObject parent, JsSettings codeSettings)
{
m_isKnownAtCompileTime = true;
m_useStrict = false;
m_settings = codeSettings;
Parent = parent;
NameTable = new Dictionary <string, JsVariableField>();
ChildScopes = new List <JsActivationObject>();
// if our parent is a scope....
if (parent != null)
{
// add us to the parent's list of child scopes
parent.ChildScopes.Add(this);
// if the parent is strict, so are we
UseStrict = parent.UseStrict;
}
// create the two lists of declared items for this scope
ScopeLookups = new HashSet <JsLookup>();
VarDeclaredNames = new HashSet <IJsNameDeclaration>();
LexicallyDeclaredNames = new HashSet <IJsNameDeclaration>();
GhostedCatchParameters = new HashSet <JsParameterDeclaration>();
GhostedFunctions = new HashSet <JsFunctionObject>();
}
private bool m_useStrict; //= false;
#endregion Fields
#region Constructors
protected JsActivationObject(JsActivationObject parent, JsSettings codeSettings)
{
m_isKnownAtCompileTime = true;
m_useStrict = false;
m_settings = codeSettings;
Parent = parent;
NameTable = new Dictionary<string, JsVariableField>();
ChildScopes = new List<JsActivationObject>();
// if our parent is a scope....
if (parent != null)
{
// add us to the parent's list of child scopes
parent.ChildScopes.Add(this);
// if the parent is strict, so are we
UseStrict = parent.UseStrict;
}
// create the two lists of declared items for this scope
ScopeLookups = new HashSet<JsLookup>();
VarDeclaredNames = new HashSet<IJsNameDeclaration>();
LexicallyDeclaredNames = new HashSet<IJsNameDeclaration>();
GhostedCatchParameters = new HashSet<JsParameterDeclaration>();
GhostedFunctions = new HashSet<JsFunctionObject>();
}
private static void ResolveGhostedCatchParameter(JsActivationObject scope, JsParameterDeclaration catchParameter)
{
// check to see if the name exists in the outer variable scope.
var ghostField = scope[catchParameter.Name];
if (ghostField == null)
{
// set up a ghost field to keep track of the relationship
ghostField = new JsVariableField(JsFieldType.GhostCatch, catchParameter.Name, 0, null)
{
OriginalContext = catchParameter.Context
};
scope.AddField(ghostField);
}
else if (ghostField.FieldType == JsFieldType.GhostCatch)
{
// there is, but it's another ghost catch variable. That's fine; just use it.
// don't even flag it as ambiguous because if someone is later referencing the error variable
// used in a couple catch variables, we'll say something then because other browsers will have that
// variable undefined or from an outer scope.
}
else
{
// there is, and it's NOT another ghosted catch variable. Possible naming
// collision in IE -- if an error happens, it will clobber the existing field's value,
// although that MAY be the intention; we don't know for sure. But it IS a cross-
// browser behavior difference.
ghostField.IsAmbiguous = true;
if (ghostField.OuterField != null)
{
// and to make matters worse, it's actually bound to an OUTER field
// in modern browsers, but will bind to this catch variable in older
// versions of IE! Definitely a cross-browser difference!
// throw a cross-browser issue error.
catchParameter.Context.HandleError(JsError.AmbiguousCatchVar);
}
}
// link them so they all keep the same name going forward
// (since they are named the same in the sources)
catchParameter.VariableField.OuterField = ghostField;
// TODO: this really should be a LIST of ghosted fields, since multiple
// elements can ghost to the same field.
ghostField.GhostedField = catchParameter.VariableField;
// if the actual field has references, we want to bubble those up
// since we're now linking those fields
if (catchParameter.VariableField.RefCount > 0)
{
// add the catch parameter's references to the ghost field
ghostField.AddReferences(catchParameter.VariableField.References);
}
}
public JsBlockScope(JsActivationObject parent, JsContext context, JsSettings settings)
: base(parent, settings)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
m_context = context.Clone();
}
private JsContext m_context; // = null;
#endregion Fields
#region Constructors
public JsBlockScope(JsActivationObject parent, JsContext context, JsSettings settings)
: base(parent, settings)
{
if (context == null)
{
throw new ArgumentNullException("context");
}
m_context = context.Clone();
}
private JsResolutionVisitor(JsActivationObject rootScope, JsSettings settings)
{
// create the lexical and variable scope stacks and push the root scope onto them
m_lexicalStack = new Stack <JsActivationObject>();
m_lexicalStack.Push(rootScope);
m_variableStack = new Stack <JsActivationObject>();
m_variableStack.Push(rootScope);
m_settings = settings;
}
private static void CreateFields(JsActivationObject scope)
{
// declare this scope
scope.DeclareScope();
// and recurse
foreach (var childScope in scope.ChildScopes)
{
CreateFields(childScope);
}
}
private JsResolutionVisitor(JsActivationObject rootScope, JsSettings settings)
{
// create the lexical and variable scope stacks and push the root scope onto them
m_lexicalStack = new Stack<JsActivationObject>();
m_lexicalStack.Push(rootScope);
m_variableStack = new Stack<JsActivationObject>();
m_variableStack.Push(rootScope);
m_settings = settings;
}
internal JsFunctionScope(JsActivationObject parent, bool isExpression, JsSettings settings, JsFunctionObject funcObj)
: base(parent, settings)
{
m_refScopes = new HashSet <JsActivationObject>();
if (isExpression)
{
// parent scopes automatically reference enclosed function expressions
AddReference(Parent);
}
FunctionObject = funcObj;
}
private static void CollapseBlockScope(JsActivationObject blockScope)
{
// copy over the stuff we want to carry over to the parent
blockScope.ScopeLookups.CopyItemsTo(blockScope.Parent.ScopeLookups);
blockScope.VarDeclaredNames.CopyItemsTo(blockScope.Parent.VarDeclaredNames);
blockScope.ChildScopes.CopyItemsTo(blockScope.Parent.ChildScopes);
blockScope.GhostedCatchParameters.CopyItemsTo(blockScope.Parent.GhostedCatchParameters);
blockScope.GhostedFunctions.CopyItemsTo(blockScope.Parent.GhostedFunctions);
// remove it from its parent's collection of child scopes
blockScope.Parent.ChildScopes.Remove(blockScope);
}
internal JsFunctionScope(JsActivationObject parent, bool isExpression, JsSettings settings, JsFunctionObject funcObj)
: base(parent, settings)
{
m_refScopes = new HashSet<JsActivationObject>();
if (isExpression)
{
// parent scopes automatically reference enclosed function expressions
AddReference(Parent);
}
FunctionObject = funcObj;
}
internal void AddReference(JsActivationObject scope)
{
// we don't want to include block scopes or with scopes -- they are really
// contained within their parents
while (scope != null && scope is JsBlockScope)
{
scope = scope.Parent;
}
if (scope != null)
{
// add the scope to the hash
m_refScopes.Add(scope);
}
}
private static void AddGhostedFields(JsActivationObject scope)
{
foreach (var catchParameter in scope.GhostedCatchParameters)
{
ResolveGhostedCatchParameter(scope, catchParameter);
}
foreach (var ghostFunc in scope.GhostedFunctions)
{
ResolveGhostedFunctions(scope, ghostFunc);
}
// recurse
foreach (var childScope in scope.ChildScopes)
{
AddGhostedFields(childScope);
}
}
public static void Apply(JsAstNode node, JsActivationObject scope, JsSettings settings)
{
if (node != null && scope != null)
{
// create the visitor and run it. This will create all the child
// scopes and populate all the scopes with the var-decl, lex-decl,
// and lookup references within them.
var visitor = new JsResolutionVisitor(scope, settings);
node.Accept(visitor);
// now that all the scopes are created and they all know what decls
// they contains, create all the fields
CreateFields(scope);
// now that all the fields have been created in all the scopes,
// let's go through and resolve all the references
ResolveLookups(scope, settings);
// now that everything is declared and resolved as per the language specs,
// we need to go back and add ghosted fields for older versions of IE that
// incorrectly implement catch-variables and named function expressions.
AddGhostedFields(scope);
}
}
public JsWithScope(JsActivationObject parent, JsContext context, JsSettings settings)
: base(parent, context, settings)
{
IsInWithScope = true;
}
public JsWithScope(JsActivationObject parent, JsContext context, JsSettings settings)
: base(parent, context, settings)
{
IsInWithScope = true;
}
internal JsCatchScope(JsActivationObject parent, JsContext catchContext, JsSettings settings, JsParameterDeclaration catchParameter)
: base(parent, catchContext, settings)
{
CatchParameter = catchParameter;
}
private static void ResolveLookups(JsActivationObject scope, JsSettings settings)
{
// resolve each lookup this scope contains
foreach (var lookup in scope.ScopeLookups)
{
ResolveLookup(scope, lookup, settings);
}
// and recurse
foreach (var childScope in scope.ChildScopes)
{
ResolveLookups(childScope, settings);
}
// mark any variables defined in this scope that don't have any references
// so we can throw warnings later. We can't rely on the reference count because
// we might remove references while optimizing code -- if we throw an error when
// the count gets to zero, then we would be reporting errors that don't exist.
// but we DO know right now what isn't referenced at all.
foreach (var field in scope.NameTable.Values)
{
if (field.RefCount == 0)
{
field.HasNoReferences = true;
}
}
}
private static void ResolveLookup(JsActivationObject scope, JsLookup lookup, JsSettings settings)
{
// resolve lookup via the lexical scope
lookup.VariableField = scope.FindReference(lookup.Name);
if (lookup.VariableField.FieldType == JsFieldType.UndefinedGlobal)
{
// couldn't find it.
// if the lookup isn't generated and isn't the object of a typeof operator,
// then we want to throw an error.
if (!lookup.IsGenerated)
{
var parentUnaryOp = lookup.Parent as JsUnaryOperator;
if (parentUnaryOp != null && parentUnaryOp.OperatorToken == JsToken.TypeOf)
{
// this undefined lookup is the target of a typeof operator.
// I think it's safe to assume we're going to use it. Don't throw an error
// and instead add it to the "known" expected globals of the global scope
MakeExpectedGlobal(lookup.VariableField);
}
else
{
// report this undefined reference
lookup.Context.ReportUndefined(lookup);
// possibly undefined global (but definitely not local).
// see if this is a function or a variable.
var callNode = lookup.Parent as JsCallNode;
var isFunction = callNode != null && callNode.Function == lookup;
lookup.Context.HandleError((isFunction ? JsError.UndeclaredFunction : JsError.UndeclaredVariable), false);
}
}
}
else if (lookup.VariableField.FieldType == JsFieldType.Predefined)
{
if (string.CompareOrdinal(lookup.Name, "window") == 0)
{
// it's the global window object
// see if it's the child of a member or call-brackets node
var member = lookup.Parent as JsMember;
if (member != null)
{
// we have window.XXXX. Add XXXX to the known globals if it
// isn't already a known item.
scope.AddGlobal(member.Name);
}
else
{
var callNode = lookup.Parent as JsCallNode;
if (callNode != null && callNode.InBrackets
&& callNode.Arguments.Count == 1
&& callNode.Arguments[0] is JsConstantWrapper
&& callNode.Arguments[0].FindPrimitiveType() == JsPrimitiveType.String)
{
// we have window["XXXX"]. See if XXXX is a valid identifier.
// TODO: we could get rid of the ConstantWrapper restriction and use an Evaluate visitor
// to evaluate the argument, since we know for sure that it's a string.
var identifier = callNode.Arguments[0].ToString();
if (JsScanner.IsValidIdentifier(identifier))
{
// Add XXXX to the known globals if it isn't already a known item.
scope.AddGlobal(identifier);
}
}
}
}
else if (settings.EvalTreatment != JsEvalTreatment.Ignore
&& string.CompareOrdinal(lookup.Name, "eval") == 0)
{
// it's an eval -- but are we calling it?
// TODO: what if we are assigning it to a variable? Should we track that variable and see if we call it?
// What about passing it as a parameter to a function? track that as well in case the function calls it?
var parentCall = lookup.Parent as JsCallNode;
if (parentCall != null && parentCall.Function == lookup)
{
scope.IsKnownAtCompileTime = false;
}
}
}
// add the reference
lookup.VariableField.AddReference(lookup);
// we are actually referencing this field, so it's no longer a placeholder field if it
// happens to have been one.
lookup.VariableField.IsPlaceholder = false;
}
private static void ResolveGhostedCatchParameter(JsActivationObject scope, JsParameterDeclaration catchParameter)
{
// check to see if the name exists in the outer variable scope.
var ghostField = scope[catchParameter.Name];
if (ghostField == null)
{
// set up a ghost field to keep track of the relationship
ghostField = new JsVariableField(JsFieldType.GhostCatch, catchParameter.Name, 0, null)
{
OriginalContext = catchParameter.Context
};
scope.AddField(ghostField);
}
else if (ghostField.FieldType == JsFieldType.GhostCatch)
{
// there is, but it's another ghost catch variable. That's fine; just use it.
// don't even flag it as ambiguous because if someone is later referencing the error variable
// used in a couple catch variables, we'll say something then because other browsers will have that
// variable undefined or from an outer scope.
}
else
{
// there is, and it's NOT another ghosted catch variable. Possible naming
// collision in IE -- if an error happens, it will clobber the existing field's value,
// although that MAY be the intention; we don't know for sure. But it IS a cross-
// browser behavior difference.
ghostField.IsAmbiguous = true;
if (ghostField.OuterField != null)
{
// and to make matters worse, it's actually bound to an OUTER field
// in modern browsers, but will bind to this catch variable in older
// versions of IE! Definitely a cross-browser difference!
// throw a cross-browser issue error.
catchParameter.Context.HandleError(JsError.AmbiguousCatchVar);
}
}
// link them so they all keep the same name going forward
// (since they are named the same in the sources)
catchParameter.VariableField.OuterField = ghostField;
// TODO: this really should be a LIST of ghosted fields, since multiple
// elements can ghost to the same field.
ghostField.GhostedField = catchParameter.VariableField;
// if the actual field has references, we want to bubble those up
// since we're now linking those fields
if (catchParameter.VariableField.RefCount > 0)
{
// add the catch parameter's references to the ghost field
ghostField.AddReferences(catchParameter.VariableField.References);
}
}
private static void CreateFields(JsActivationObject scope)
{
// declare this scope
scope.DeclareScope();
// and recurse
foreach (var childScope in scope.ChildScopes)
{
CreateFields(childScope);
}
}
public static void Apply(JsAstNode node, JsActivationObject scope, JsSettings settings)
{
if (node != null && scope != null)
{
// create the visitor and run it. This will create all the child
// scopes and populate all the scopes with the var-decl, lex-decl,
// and lookup references within them.
var visitor = new JsResolutionVisitor(scope, settings);
node.Accept(visitor);
// now that all the scopes are created and they all know what decls
// they contains, create all the fields
CreateFields(scope);
// now that all the fields have been created in all the scopes,
// let's go through and resolve all the references
ResolveLookups(scope, settings);
// now that everything is declared and resolved as per the language specs,
// we need to go back and add ghosted fields for older versions of IE that
// incorrectly implement catch-variables and named function expressions.
AddGhostedFields(scope);
}
}
private static void CollapseBlockScope(JsActivationObject blockScope)
{
// copy over the stuff we want to carry over to the parent
blockScope.ScopeLookups.CopyItemsTo(blockScope.Parent.ScopeLookups);
blockScope.VarDeclaredNames.CopyItemsTo(blockScope.Parent.VarDeclaredNames);
blockScope.ChildScopes.CopyItemsTo(blockScope.Parent.ChildScopes);
blockScope.GhostedCatchParameters.CopyItemsTo(blockScope.Parent.GhostedCatchParameters);
blockScope.GhostedFunctions.CopyItemsTo(blockScope.Parent.GhostedFunctions);
// remove it from its parent's collection of child scopes
blockScope.Parent.ChildScopes.Remove(blockScope);
}
private static void AddGhostedFields(JsActivationObject scope)
{
foreach (var catchParameter in scope.GhostedCatchParameters)
{
ResolveGhostedCatchParameter(scope, catchParameter);
}
foreach (var ghostFunc in scope.GhostedFunctions)
{
ResolveGhostedFunctions(scope, ghostFunc);
}
// recurse
foreach (var childScope in scope.ChildScopes)
{
AddGhostedFields(childScope);
}
}
private static void ResolveLookup(JsActivationObject scope, JsLookup lookup, JsSettings settings)
{
// resolve lookup via the lexical scope
lookup.VariableField = scope.FindReference(lookup.Name);
if (lookup.VariableField.FieldType == JsFieldType.UndefinedGlobal)
{
// couldn't find it.
// if the lookup isn't generated and isn't the object of a typeof operator,
// then we want to throw an error.
if (!lookup.IsGenerated)
{
var parentUnaryOp = lookup.Parent as JsUnaryOperator;
if (parentUnaryOp != null && parentUnaryOp.OperatorToken == JsToken.TypeOf)
{
// this undefined lookup is the target of a typeof operator.
// I think it's safe to assume we're going to use it. Don't throw an error
// and instead add it to the "known" expected globals of the global scope
MakeExpectedGlobal(lookup.VariableField);
}
else
{
// report this undefined reference
lookup.Context.ReportUndefined(lookup);
// possibly undefined global (but definitely not local).
// see if this is a function or a variable.
var callNode = lookup.Parent as JsCallNode;
var isFunction = callNode != null && callNode.Function == lookup;
lookup.Context.HandleError((isFunction ? JsError.UndeclaredFunction : JsError.UndeclaredVariable), false);
}
}
}
else if (lookup.VariableField.FieldType == JsFieldType.Predefined)
{
if (string.CompareOrdinal(lookup.Name, "window") == 0)
{
// it's the global window object
// see if it's the child of a member or call-brackets node
var member = lookup.Parent as JsMember;
if (member != null)
{
// we have window.XXXX. Add XXXX to the known globals if it
// isn't already a known item.
scope.AddGlobal(member.Name);
}
else
{
var callNode = lookup.Parent as JsCallNode;
if (callNode != null && callNode.InBrackets &&
callNode.Arguments.Count == 1 &&
callNode.Arguments[0] is JsConstantWrapper &&
callNode.Arguments[0].FindPrimitiveType() == JsPrimitiveType.String)
{
// we have window["XXXX"]. See if XXXX is a valid identifier.
// TODO: we could get rid of the ConstantWrapper restriction and use an Evaluate visitor
// to evaluate the argument, since we know for sure that it's a string.
var identifier = callNode.Arguments[0].ToString();
if (JsScanner.IsValidIdentifier(identifier))
{
// Add XXXX to the known globals if it isn't already a known item.
scope.AddGlobal(identifier);
}
}
}
}
else if (settings.EvalTreatment != JsEvalTreatment.Ignore &&
string.CompareOrdinal(lookup.Name, "eval") == 0)
{
// it's an eval -- but are we calling it?
// TODO: what if we are assigning it to a variable? Should we track that variable and see if we call it?
// What about passing it as a parameter to a function? track that as well in case the function calls it?
var parentCall = lookup.Parent as JsCallNode;
if (parentCall != null && parentCall.Function == lookup)
{
scope.IsKnownAtCompileTime = false;
}
}
}
// add the reference
lookup.VariableField.AddReference(lookup);
// we are actually referencing this field, so it's no longer a placeholder field if it
// happens to have been one.
lookup.VariableField.IsPlaceholder = false;
}
internal void AddReference(JsActivationObject scope)
{
// we don't want to include block scopes or with scopes -- they are really
// contained within their parents
while (scope != null && scope is JsBlockScope)
{
scope = scope.Parent;
}
if (scope != null)
{
// add the scope to the hash
m_refScopes.Add(scope);
}
}
private static void ResolveGhostedFunctions(JsActivationObject scope, JsFunctionObject funcObject)
{
var functionField = funcObject.VariableField;
// let's check on ghosted names in the outer variable scope
var ghostField = scope[funcObject.Name];
if (ghostField == null)
{
// nothing; good to go. Add a ghosted field to keep track of it.
ghostField = new JsVariableField(JsFieldType.GhostFunction, funcObject.Name, 0, funcObject)
{
OriginalContext = functionField.OriginalContext,
CanCrunch = funcObject.VariableField.IfNotNull(v => v.CanCrunch)
};
scope.AddField(ghostField);
}
else if (ghostField.FieldType == JsFieldType.GhostFunction)
{
// there is, but it's another ghosted function expression.
// what if a lookup is resolved to this field later? We probably still need to
// at least flag it as ambiguous. We will only need to throw an error, though,
// if someone actually references the outer ghost variable.
ghostField.IsAmbiguous = true;
}
else
{
// something already exists. Could be a naming collision for IE or at least a
// a cross-browser behavior difference if it's not coded properly.
// mark this field as a function, even if it wasn't before
ghostField.IsFunction = true;
if (ghostField.OuterField != null)
{
// if the pre-existing field we are ghosting is a reference to
// an OUTER field, then we actually have a problem that creates a BIG
// difference between older IE browsers and everything else.
// modern browsers will have the link to the outer field, but older
// IE browsers will link to this function expression!
// fire a cross-browser error warning
ghostField.IsAmbiguous = true;
funcObject.IdContext.HandleError(JsError.AmbiguousNamedFunctionExpression);
}
else if (ghostField.IsReferenced)
{
// if the ghosted field isn't even referenced, then who cares?
// but it is referenced. Let's see if it matters.
// something like: var nm = function nm() {}
// is TOTALLY cool common cross-browser syntax.
var parentVarDecl = funcObject.Parent as JsVariableDeclaration;
if (parentVarDecl == null
|| parentVarDecl.Name != funcObject.Name)
{
// see if it's a simple assignment.
// something like: var nm; nm = function nm(){},
// would also be cool, although less-common than the vardecl version.
JsLookup lookup;
var parentAssignment = funcObject.Parent as JsBinaryOperator;
if (parentAssignment == null || parentAssignment.OperatorToken != JsToken.Assign
|| parentAssignment.Operand2 != funcObject
|| (lookup = parentAssignment.Operand1 as JsLookup) == null
|| lookup.Name != funcObject.Name)
{
// something else. Flag it as ambiguous.
ghostField.IsAmbiguous = true;
}
}
}
}
// link them so they all keep the same name going forward
// (since they are named the same in the sources)
functionField.OuterField = ghostField;
// TODO: this really should be a LIST of ghosted fields, since multiple
// elements can ghost to the same field.
ghostField.GhostedField = functionField;
// if the actual field has references, we want to bubble those up
// since we're now linking those fields
if (functionField.RefCount > 0)
{
// add the function's references to the ghost field
ghostField.AddReferences(functionField.References);
}
}
internal JsCatchScope(JsActivationObject parent, JsContext catchContext, JsSettings settings, JsParameterDeclaration catchParameter)
: base(parent, catchContext, settings)
{
CatchParameter = catchParameter;
}
private static void ResolveGhostedFunctions(JsActivationObject scope, JsFunctionObject funcObject)
{
var functionField = funcObject.VariableField;
// let's check on ghosted names in the outer variable scope
var ghostField = scope[funcObject.Name];
if (ghostField == null)
{
// nothing; good to go. Add a ghosted field to keep track of it.
ghostField = new JsVariableField(JsFieldType.GhostFunction, funcObject.Name, 0, funcObject)
{
OriginalContext = functionField.OriginalContext,
CanCrunch = funcObject.VariableField.IfNotNull(v => v.CanCrunch)
};
scope.AddField(ghostField);
}
else if (ghostField.FieldType == JsFieldType.GhostFunction)
{
// there is, but it's another ghosted function expression.
// what if a lookup is resolved to this field later? We probably still need to
// at least flag it as ambiguous. We will only need to throw an error, though,
// if someone actually references the outer ghost variable.
ghostField.IsAmbiguous = true;
}
else
{
// something already exists. Could be a naming collision for IE or at least a
// a cross-browser behavior difference if it's not coded properly.
// mark this field as a function, even if it wasn't before
ghostField.IsFunction = true;
if (ghostField.OuterField != null)
{
// if the pre-existing field we are ghosting is a reference to
// an OUTER field, then we actually have a problem that creates a BIG
// difference between older IE browsers and everything else.
// modern browsers will have the link to the outer field, but older
// IE browsers will link to this function expression!
// fire a cross-browser error warning
ghostField.IsAmbiguous = true;
funcObject.IdContext.HandleError(JsError.AmbiguousNamedFunctionExpression);
}
else if (ghostField.IsReferenced)
{
// if the ghosted field isn't even referenced, then who cares?
// but it is referenced. Let's see if it matters.
// something like: var nm = function nm() {}
// is TOTALLY cool common cross-browser syntax.
var parentVarDecl = funcObject.Parent as JsVariableDeclaration;
if (parentVarDecl == null ||
parentVarDecl.Name != funcObject.Name)
{
// see if it's a simple assignment.
// something like: var nm; nm = function nm(){},
// would also be cool, although less-common than the vardecl version.
JsLookup lookup;
var parentAssignment = funcObject.Parent as JsBinaryOperator;
if (parentAssignment == null || parentAssignment.OperatorToken != JsToken.Assign ||
parentAssignment.Operand2 != funcObject ||
(lookup = parentAssignment.Operand1 as JsLookup) == null ||
lookup.Name != funcObject.Name)
{
// something else. Flag it as ambiguous.
ghostField.IsAmbiguous = true;
}
}
}
}
// link them so they all keep the same name going forward
// (since they are named the same in the sources)
functionField.OuterField = ghostField;
// TODO: this really should be a LIST of ghosted fields, since multiple
// elements can ghost to the same field.
ghostField.GhostedField = functionField;
// if the actual field has references, we want to bubble those up
// since we're now linking those fields
if (functionField.RefCount > 0)
{
// add the function's references to the ghost field
ghostField.AddReferences(functionField.References);
}
}