public void WithDirectives()
{
/* Given */
InterfaceDefinition original = @"interface Inf";
/* When */
var modified = original
.WithDirectives(new List <Directive>
{
"@a"
});
/* Then */
Assert.Null(original.Directives);
Assert.NotNull(modified.Directives);
var a = Assert.Single(modified.Directives);
Assert.Equal("a", a?.Name);
}
