static void PopulateGenericParameters(IGenericParameterProvider publicType, CodeTypeParameterCollection parameters, HashSet <string> excludeAttributes)
{
foreach (var parameter in publicType.GenericParameters)
{
// A little hacky. Means we get "in" and "out" prefixed on any constraints, but it's either that
// or add it as a custom attribute
var name = parameter.Name;
if (parameter.IsCovariant)
{
name = "out " + name;
}
if (parameter.IsContravariant)
{
name = "in " + name;
}
var attributeCollection = new CodeAttributeDeclarationCollection();
if (parameter.HasCustomAttributes)
{
PopulateCustomAttributes(parameter, attributeCollection, excludeAttributes);
}
var typeParameter = new CodeTypeParameter(name)
{
HasConstructorConstraint =
parameter.HasDefaultConstructorConstraint && !parameter.HasNotNullableValueTypeConstraint
};
typeParameter.CustomAttributes.AddRange(attributeCollection.OfType <CodeAttributeDeclaration>().ToArray());
if (parameter.HasNotNullableValueTypeConstraint)
{
typeParameter.Constraints.Add(" struct"); // Extra space is a hack!
}
if (parameter.HasReferenceTypeConstraint)
{
typeParameter.Constraints.Add(" class");
}
foreach (var constraint in parameter.Constraints.Where(t => t.FullName != "System.ValueType"))
{
// for generic constraints like IEnumerable<T> call to GetElementType() returns TypeReference with Name = !0
typeParameter.Constraints.Add(CreateCodeTypeReference(constraint /*.GetElementType()*/));
}
parameters.Add(typeParameter);
}
}
static void PopulateGenericParameters(IGenericParameterProvider publicType, CodeTypeParameterCollection parameters, AttributeFilter attributeFilter, Func <GenericParameter, bool> shouldUseParameter)
{
foreach (var parameter in publicType.GenericParameters.Where(shouldUseParameter))
{
// A little hacky. Means we get "in" and "out" prefixed on any constraints, but it's either that
// or add it as a custom attribute
var name = parameter.Name;
if (parameter.IsCovariant)
{
name = "out " + name;
}
if (parameter.IsContravariant)
{
name = "in " + name;
}
var attributeCollection = new CodeAttributeDeclarationCollection();
if (parameter.HasCustomAttributes)
{
PopulateCustomAttributes(parameter, attributeCollection, attributeFilter);
}
var typeParameter = new CodeTypeParameter(name)
{
HasConstructorConstraint =
parameter.HasDefaultConstructorConstraint && !parameter.HasNotNullableValueTypeConstraint
};
typeParameter.CustomAttributes.AddRange(attributeCollection.OfType <CodeAttributeDeclaration>().ToArray());
var nullableConstraint = parameter.GetNullabilityMap().First();
var unmanagedConstraint = parameter.CustomAttributes.Any(attr => attr.AttributeType.FullName == "System.Runtime.CompilerServices.IsUnmanagedAttribute");
if (parameter.HasNotNullableValueTypeConstraint)
{
typeParameter.Constraints.Add(unmanagedConstraint ? " unmanaged" : " struct");
}
if (parameter.HasReferenceTypeConstraint)
{
typeParameter.Constraints.Add(nullableConstraint == true ? " class?" : " class");
}
else if (nullableConstraint == false)
{
typeParameter.Constraints.Add(" notnull");
}
using (NullableContext.Push(parameter))
{
foreach (var constraint in parameter.Constraints.Where(constraint => !IsSpecialConstraint(constraint)))
{
// for generic constraints like IEnumerable<T> call to GetElementType() returns TypeReference with Name = !0
var typeReference = constraint.ConstraintType /*.GetElementType()*/.CreateCodeTypeReference(constraint);
typeParameter.Constraints.Add(typeReference);
}
}
parameters.Add(typeParameter);
}
bool IsSpecialConstraint(GenericParameterConstraint constraint)
{
// struct
if (constraint.ConstraintType is TypeReference reference && reference.FullName == "System.ValueType")
{
return(true);
}
// unmanaged
if (constraint.ConstraintType.IsUnmanaged())
{
return(true);
}
return(false);
}
}