public void Document_With_Location_Null()
{
// arrange
var location = new Location(0, 0, 0, 0);
var fragment = new FragmentDefinitionNode(
null, new NameNode("foo"),
Array.Empty <VariableDefinitionNode>(),
new NamedTypeNode("foo"),
Array.Empty <DirectiveNode>(),
new SelectionSetNode(Array.Empty <ISelectionNode>()));
var document = new DocumentNode(location, new IDefinitionNode[] { fragment });
// act
document = document.WithLocation(null);
// assert
Assert.Null(document.Location);
}