use tempdb;
set implicit_transactions off;
go

if @@trancount > 0 rollback;
go

create table dbo.t (id int primary key);
insert into dbo.t values (1);
go

set implicit_transactions on;
if exists(select 1 from dbo.t with (repeatableread) where id = 1)
 select * from (select @@trancount) a([@@trancount]) outer apply (select * from sys.dm_tran_locks where request_session_id = @@spid) l;

if @@trancount > 0 rollback;
go

set implicit_transactions off;
begin tran;
if exists(select 1 from dbo.t with (repeatableread) where id = 1)
 select * from (select @@trancount) a([@@trancount]) outer apply (select * from sys.dm_tran_locks where request_session_id = @@spid) l;

if @@trancount > 0 rollback;
go

set implicit_transactions on;
begin tran;
select @@trancount as [@@trancount];

if @@trancount > 0 rollback;
go

set implicit_transactions off;
go

drop table dbo.t;
go