There are questions telling me what to look for in a new bike or a second hand one, and things to look for during my test ride, but nothing about what I should actually do during my test ride. That last question has been updated to say "What should I actually do on the test drive?" but the answers don't really address that.
I assume I need to make sure the brakes and gears etc all work, but how do I do that? Just change into each gear, or do so while pedaling hard? Should that even work? Is braking hard enough to lift the rear wheel a legitimate test? Is it reasonable to (say) ride each bike round the same 10 minute circuit as fast as I can to see which ones feel best at speed (assume I'm buying a fast road bike)?
What should I do for a 5-10 minute test ride on each bike I look at? What about a quick 30 seconds in a car park if that's all I can get?