private static Declaration SelectedDeclarationViaArgument(QualifiedSelection qualifiedSelection, DeclarationFinder finder)
{
var members = finder.Members(qualifiedSelection.QualifiedName)
.Where(m => (m.DeclarationType.HasFlag(DeclarationType.Procedure) || // includes PropertyLet and PropertySet and LibraryProcedure
m.DeclarationType.HasFlag(DeclarationType.Function)) && // includes PropertyGet and LibraryFunction
!m.DeclarationType.HasFlag(DeclarationType.LibraryFunction) &&
!m.DeclarationType.HasFlag(DeclarationType.LibraryProcedure));
var enclosingProcedure = members.SingleOrDefault(m => m.Context.GetSelection().Contains(qualifiedSelection.Selection));
if (enclosingProcedure == null)
{
return(null);
}
var allArguments = enclosingProcedure.Context.GetDescendents <VBAParser.ArgumentContext>();
var context = allArguments
.Where(arg => arg.missingArgument() == null)
.FirstOrDefault(m =>
{
var isOnWhitespace = false;
if (m.TryGetPrecedingContext <VBAParser.WhiteSpaceContext>(out var whitespace))
{
isOnWhitespace = whitespace.GetSelection().ContainsFirstCharacter(qualifiedSelection.Selection);
}
return(isOnWhitespace || m.GetSelection().ContainsFirstCharacter(qualifiedSelection.Selection));
});
var skippedArg = allArguments
.Where(arg => arg.missingArgument() != null)
.FirstOrDefault(m =>
{
var isOnWhitespace = false;
if (m.TryGetPrecedingContext <VBAParser.WhiteSpaceContext>(out var whitespace))
{
isOnWhitespace = whitespace.GetSelection().ContainsFirstCharacter(qualifiedSelection.Selection);
}
return(isOnWhitespace || m.GetSelection().ContainsFirstCharacter(qualifiedSelection.Selection));
});
context = context ?? skippedArg;
if (context != null)
{
return((Declaration)finder.FindParameterOfNonDefaultMemberFromSimpleArgumentNotPassedByValExplicitly(context, enclosingProcedure)
?? finder.FindInvokedMemberFromArgumentContext(context, qualifiedSelection.QualifiedName)); // fallback to the invoked procedure declaration
}
return(null);
}
private static bool IsAssignedByRefArgument(Declaration enclosingProcedure, IdentifierReference reference, DeclarationFinder finder)
{
var argExpression = ImmediateArgumentExpressionContext(reference);
if (argExpression is null)
{
return(false);
}
var parameter = finder.FindParameterOfNonDefaultMemberFromSimpleArgumentNotPassedByValExplicitly(argExpression, enclosingProcedure);
// note: not recursive, by design.
return(parameter != null &&
(parameter.IsImplicitByRef || parameter.IsByRef) &&
parameter.References.Any(r => r.IsAssignment));
}
private static bool IsPotentiallyAssignedByRefArgument(QualifiedModuleName module, IdentifierReference reference, DeclarationFinder finder)
{
var argExpression = ImmediateArgumentExpressionContext(reference);
if (argExpression == null)
{
return(false);
}
var parameter = finder.FindParameterOfNonDefaultMemberFromSimpleArgumentNotPassedByValExplicitly(argExpression, module);
if (parameter == null)
{
//We have no idea what parameter it is passed to as argument. So, we have to err on the safe side and assume it is passed by reference.
return(true);
}
//We do not check whether the argument the parameter is actually assigned to costly recursions.
return(parameter.IsByRef);
}
private static bool IsUsageAsAssignedToByRefArgument(IdentifierReference reference, DeclarationFinder finder)
{
var argExpression = ImmediateArgumentExpressionContext(reference);
if (argExpression == null)
{
return(false);
}
var parameter = finder.FindParameterOfNonDefaultMemberFromSimpleArgumentNotPassedByValExplicitly(argExpression, reference.QualifiedModuleName);
if (parameter == null)
{
//We have no idea what parameter it is passed to as argument. So, we have to err on the safe side and assume it is not passed by reference.
return(false);
}
//We go only one level deep and make a conservative check to avoid a potentially costly recursion.
return(parameter.IsByRef &&
parameter.References.Any(paramReference => paramReference.IsAssignment));
}
