public async Task GetExistsAsync()
{
int key = 1;
Expression <Func <Customer, bool> > predicate = x => true;
var options = new QueryOptions <Customer>();
var mock = new Mock <IService <Customer> >();
mock.Setup(x => x.GetExistsAsync(It.IsAny <int>(), It.IsAny <CancellationToken>()));
mock.Setup(x => x.GetExistsAsync(It.IsAny <Expression <Func <Customer, bool> > >(), It.IsAny <CancellationToken>()));
mock.Setup(x => x.GetExistsAsync(It.IsAny <IQueryOptions <Customer> >(), It.IsAny <CancellationToken>()));
var readOnlyService = new ReadOnlyServiceWrapper <Customer, int>(mock.Object);
await readOnlyService.GetExistsAsync(key);
await readOnlyService.GetExistsAsync(predicate);
await readOnlyService.GetExistsAsync(options);
mock.Verify(x => x.GetExistsAsync(key, default(CancellationToken)), Times.Once);
mock.Verify(x => x.GetExistsAsync(predicate, default(CancellationToken)), Times.Once);
mock.Verify(x => x.GetExistsAsync(options, default(CancellationToken)), Times.Once);
}
