Drug tests are the norm in sports.
Or for better words, a doping test is the norm. And its enforced by the anti-doping agencies of the countries. In team-sports there is a huge lack of testing though compared to most other sports (track and field for example are highly tested, even I got tested back in my teens). And yes the WADA also includes recreational drugs as doping (even weed ^^). And people got busted for that.
Best example: maradonna got banned for cocaine in 90/91 and got banned for 15 months for cocaine. Later he also got banned for using ephedrine when tested during the
WC in 94.
Now lets come to the NHL. The NHL uses
the WADA rules and tests atleast twice.
And while the tests seem not to be conducted by the USADA (US anti-doping agency), they should be using the same tests and practices.
Here is a more updated info about the anti-doping/ drug policy of the NHL.
The whole discussion about testing for drugs is absurd, because its stated in the CBA that they test for drugs. And it is more than common in every other sport to do drug/doping tests. And while we can discuss what substances should be tested for (alcohol is not on the list, but weed is which is kinda dumb), there is no real point to discuss if there even should be tests.