I don't know if I'm repeating myself but:
I fly at an controlled airport. Sometimes I'm cleared base and final, sometimes I'm cleared base only. I presume, this means there's a difference. Therefore I should not turn final without clearance to do so.
I've flown at another controlled airport where, if it's quiet, the controller will ask you to report BEFORE base, then clear you to base, and ask you to report BEFORE final then clear you to final, then clear you to land. I know he got stroppy with me for turning base without clearance.
I remember an old joke where they say "Final is when you don't have to turn anymore to land."
I still would have difficulty turning final without the appropriate clearance to do so.
Carlito.