private bool IsTypeAccessible(ITypeNode type)
{
// type not declared --> treat it as accessible
if (type == null)
{
return(true);
}
// predefined types are always accessible
if (type.IsPredefinedType())
{
return(true);
}
// descend into ParenthesizedType
if (type.Kind == TypeScript.Net.Types.SyntaxKind.ParenthesizedType)
{
return(IsTypeAccessible(type.Cast <IParenthesizedTypeNode>().Type));
}
// an array type is accessible iff its element type is accessible
if (type.Kind == TypeScript.Net.Types.SyntaxKind.ArrayType)
{
return(IsTypeAccessible(type.Cast <IArrayTypeNode>().ElementType));
}
// a union type is accessible iff all its types are accessible
if (type.Kind == TypeScript.Net.Types.SyntaxKind.UnionType)
{
return(type.Cast <IUnionOrIntersectionTypeNode>().Types.All(t => IsTypeAccessible(t)));
}
// a function type is accessible iff its return type and its type parameters are accessible
if (type.Kind == TypeScript.Net.Types.SyntaxKind.FunctionType)
{
var fnType = type.Cast <IFunctionOrConstructorTypeNode>();
var fnParameters = fnType.Parameters ?? NodeArray.Empty <IParameterDeclaration>();
return
(IsTypeAccessible(fnType.Type) &&
fnParameters.All(tp => IsTypeAccessible(tp.Type)));
}
// a type literal is accessible iff all its members are accessible
if (type.Kind == TypeScript.Net.Types.SyntaxKind.TypeLiteral)
{
return(type.Cast <ITypeLiteralNode>().Members.All(m => IsMemberAccessible(m)));
bool IsMemberAccessible(ITypeElement e)
{
var memberTypes = e.Kind == TypeScript.Net.Types.SyntaxKind.PropertySignature
? new[] { e.Cast <IPropertySignature>().Type }
: null; // handle other kinds if needed
return(memberTypes != null && memberTypes.All(t => IsTypeAccessible(t)));
}
}
// if any type argument is inaccessible, this type is not accessible either
var typeArguments = type.GetTypeArguments();
if (!typeArguments.All(t => IsTypeAccessible(t)))
{
return(false);
}
// if this type couldn't be resolved, treat it as inaccessible
var resolvedSymbol = type.ResolvedSymbol;
if (resolvedSymbol == null)
{
return(false);
}
// otherwise, a type is accessible if any of its declarations is either explicitly exported or defined in the prelude
return(resolvedSymbol
.GetDeclarations()
.Any(d =>
d.IsExported() ||
m_semanticModel.TypeChecker.IsPreludeDeclaration(d)));
}