public void SingleOrDefault_IQueryableOfT_ZeroElementsInSequence_ReturnsNull()
{
IQueryable <Customer> queryable = Enumerable.Empty <Customer>().AsQueryable();
HttpActionDescriptor actionDescriptor = new Mock <HttpActionDescriptor>().Object;
var result = QueryableAttribute.SingleOrDefault(queryable, actionDescriptor);
Assert.Null(result);
}
public void SingleOrDefault_IQueryableOfT_OneElementInSequence_ReturnsElement()
{
Customer customer = new Customer();
IQueryable <Customer> queryable = new[] { customer }.AsQueryable();
HttpActionDescriptor actionDescriptor = new Mock <HttpActionDescriptor>().Object;
var result = QueryableAttribute.SingleOrDefault(queryable, actionDescriptor);
Assert.Same(customer, result);
}
public void SingleOrDefault_IQueryableOfT_MoreThaneOneElementInSequence_Throws()
{
IQueryable <Customer> queryable = new[] { new Customer(), new Customer() }.AsQueryable();
ReflectedHttpActionDescriptor actionDescriptor = new ReflectedHttpActionDescriptor
{
Configuration = new HttpConfiguration(),
MethodInfo = GetType().GetMethod("SomeAction", BindingFlags.Instance | BindingFlags.NonPublic),
ControllerDescriptor = new HttpControllerDescriptor {
ControllerName = "SomeName"
}
};
Assert.Throws <InvalidOperationException>(
() => QueryableAttribute.SingleOrDefault(queryable, actionDescriptor),
"The action 'SomeAction' on controller 'SomeName' returned a SingleResult containing more than one element. " +
"SingleResult must have zero or one elements.");
}