public static Accessibility DetermineAccessibilityConstraint(
this SemanticModel semanticModel,
TypeSyntax type,
CancellationToken cancellationToken)
{
if (type == null)
{
return Accessibility.Private;
}
type = GetOutermostType(type);
// Interesting cases based on 3.5.4 Accessibility constraints in the language spec.
// If any of the below hold, then we will override the default accessibility if the
// constraint wants the type to be more accessible. i.e. if by default we generate
// 'internal', but a constraint makes us 'public', then be public.
// 1) The direct base class of a class type must be at least as accessible as the
// class type itself.
//
// 2) The explicit base interfaces of an interface type must be at least as accessible
// as the interface type itself.
if (type != null)
{
if (type.Parent is BaseTypeSyntax && type.Parent.IsParentKind(SyntaxKind.BaseList) && ((BaseTypeSyntax)type.Parent).Type == type)
{
var containingType = semanticModel.GetDeclaredSymbol(type.GetAncestor<BaseTypeDeclarationSyntax>(), cancellationToken) as INamedTypeSymbol;
if (containingType != null && containingType.TypeKind == TypeKind.Interface)
{
return containingType.DeclaredAccessibility;
}
else if (((BaseListSyntax)type.Parent.Parent).Types[0] == type.Parent)
{
return containingType.DeclaredAccessibility;
}
}
}
// 4) The type of a constant must be at least as accessible as the constant itself.
// 5) The type of a field must be at least as accessible as the field itself.
if (type.IsParentKind(SyntaxKind.VariableDeclaration) &&
type.Parent.IsParentKind(SyntaxKind.FieldDeclaration))
{
var variableDeclaration = (VariableDeclarationSyntax)type.Parent;
return ((ISymbol)semanticModel.GetDeclaredSymbol(
variableDeclaration.Variables[0], cancellationToken)).DeclaredAccessibility;
}
// 3) The return type of a delegate type must be at least as accessible as the
// delegate type itself.
// 6) The return type of a method must be at least as accessible as the method
// itself.
// 7) The type of a property must be at least as accessible as the property itself.
// 8) The type of an event must be at least as accessible as the event itself.
// 9) The type of an indexer must be at least as accessible as the indexer itself.
// 10) The return type of an operator must be at least as accessible as the operator
// itself.
if (type.IsParentKind(SyntaxKind.DelegateDeclaration) ||
type.IsParentKind(SyntaxKind.MethodDeclaration) ||
type.IsParentKind(SyntaxKind.PropertyDeclaration) ||
type.IsParentKind(SyntaxKind.EventDeclaration) ||
type.IsParentKind(SyntaxKind.IndexerDeclaration) ||
type.IsParentKind(SyntaxKind.OperatorDeclaration))
{
return semanticModel.GetDeclaredSymbol(
type.Parent, cancellationToken).DeclaredAccessibility;
}
// 3) The parameter types of a delegate type must be at least as accessible as the
// delegate type itself.
// 6) The parameter types of a method must be at least as accessible as the method
// itself.
// 9) The parameter types of an indexer must be at least as accessible as the
// indexer itself.
// 10) The parameter types of an operator must be at least as accessible as the
// operator itself.
// 11) The parameter types of an instance constructor must be at least as accessible
// as the instance constructor itself.
if (type.IsParentKind(SyntaxKind.Parameter) && type.Parent.IsParentKind(SyntaxKind.ParameterList))
{
if (type.Parent.Parent.IsParentKind(SyntaxKind.DelegateDeclaration) ||
type.Parent.Parent.IsParentKind(SyntaxKind.MethodDeclaration) ||
type.Parent.Parent.IsParentKind(SyntaxKind.IndexerDeclaration) ||
type.Parent.Parent.IsParentKind(SyntaxKind.OperatorDeclaration))
{
return semanticModel.GetDeclaredSymbol(
type.Parent.Parent.Parent, cancellationToken).DeclaredAccessibility;
}
if (type.Parent.Parent.IsParentKind(SyntaxKind.ConstructorDeclaration))
{
var symbol = semanticModel.GetDeclaredSymbol(type.Parent.Parent.Parent, cancellationToken);
if (!symbol.IsStatic)
{
return symbol.DeclaredAccessibility;
}
}
}
// 8) The type of an event must be at least as accessible as the event itself.
if (type.IsParentKind(SyntaxKind.VariableDeclaration) &&
type.Parent.IsParentKind(SyntaxKind.EventFieldDeclaration))
{
var variableDeclaration = (VariableDeclarationSyntax)type.Parent;
var symbol = semanticModel.GetDeclaredSymbol(variableDeclaration.Variables[0], cancellationToken);
if (symbol != null)
{
return ((ISymbol)symbol).DeclaredAccessibility;
}
}
return Accessibility.Private;
}
