AssignableFromConstraint - jnm2/nunit-docs-wiki GitHub Wiki
AssignableFromConstraint tests that one type is assignable from another
AssignableFromConstraint(Type)
Is.AssignableFrom(Type)
Is.AssignableFrom<T>()
Assert.That("Hello", Is.AssignableFrom(typeof(string)));
Assert.That(5, Is.Not.AssignableFrom(typeof(string)));