/// <summary>
/// Returns the constructed form of the provided generic type.
/// </summary>
public static IdSpan GetConstructed(this TypeConverter formatter, IdSpan unconstructed, params Type[] typeArguments)
{
var typeString = unconstructed.AsSpan();
var indicatorIndex = typeString.IndexOf((byte)GenericTypeIndicator);
var arityString = typeString.Slice(indicatorIndex + 1);
if (indicatorIndex < 0 || arityString.IndexOf((byte)StartArgument) >= 0)
{
throw new InvalidOperationException("Cannot construct an already-constructed type");
}
if (!Utf8Parser.TryParse(arityString, out int arity, out var len) || len < arityString.Length || typeArguments.Length != arity)
{
throw new InvalidOperationException($"Insufficient number of type arguments, {typeArguments.Length}, provided while constructing type \"{unconstructed}\"");
}
var typeSpecs = new TypeSpec[typeArguments.Length];
for (var i = 0; i < typeArguments.Length; i++)
{
typeSpecs[i] = RuntimeTypeNameParser.Parse(formatter.Format(typeArguments[i]));
}
var constructed = new ConstructedGenericTypeSpec(new NamedTypeSpec(null, unconstructed.ToStringUtf8(), typeArguments.Length), typeSpecs).Format();
return(IdSpan.Create(constructed));
}
/// <summary>
/// Returns the type arguments for the provided constructed generic type string.
/// </summary>
public static Type[] GetArguments(this TypeConverter formatter, IdSpan constructed)
{
var str = constructed.AsSpan();
var index = str.IndexOf((byte)StartArgument);
if (index <= 0)
{
return(Array.Empty <Type>());
}
var safeString = "safer" + str.Slice(str.IndexOf((byte)GenericTypeIndicator)).GetUtf8String();
var parsed = RuntimeTypeNameParser.Parse(safeString);
if (!(parsed is ConstructedGenericTypeSpec spec))
{
throw new InvalidOperationException($"Unable to correctly parse grain type {constructed}");
}
var result = new Type[spec.Arguments.Length];
for (var i = 0; i < result.Length; i++)
{
var arg = spec.Arguments[i];
var formattedArg = arg.Format();
result[i] = formatter.Parse(formattedArg);
if (result[i] is null)
{
throw new InvalidOperationException($"Unable to parse argument \"{formattedArg}\" as a type for grain type \"{constructed}\"");
}
}
return(result);
}
private static (TypeSpec Type, string Assembly) HandleNamedType(NamedTypeSpec type, string assemblyName, Func <QualifiedType, QualifiedType> replaceTypeName)
{
var nsQualified = type.GetNamespaceQualifiedName();
var names = replaceTypeName(new QualifiedType(assembly: assemblyName, type: nsQualified));
if (!string.Equals(nsQualified, names.Type, StringComparison.Ordinal))
{
// Change the type name and potentially the assembly.
var resultType = RuntimeTypeNameParser.Parse(names.Type);
if (!(resultType is NamedTypeSpec))
{
throw new InvalidOperationException($"Replacement type name, \"{names.Type}\", can not deviate from the original type structure of the input, \"{nsQualified}\"");
}
return(resultType, names.Assembly);
}
else if (!string.Equals(assemblyName, names.Assembly, StringComparison.Ordinal))
{
// Only change the assembly;
return(type, names.Assembly);
}
else if (type.ContainingType is object)
{
// Give the user an opportunity to change the parent, including the assembly.
var replacementParent = ApplyInner(type.ContainingType, assemblyName, replaceTypeName);
if (ReferenceEquals(replacementParent.Type, type.ContainingType))
{
// No change to the type.
return(type, replacementParent.Assembly);
}
// The parent type changed.
var typedReplacement = (NamedTypeSpec)replacementParent.Type;
return(new NamedTypeSpec(typedReplacement, type.Name, type.Arity), replacementParent.Assembly);
}
else
{
return(type, names.Assembly);
}
}
