Just arrived at the Raffles Jakarta which now has a lounge. Checked in at 8:15pm and the evening canapés go from 6-9pm(!!!)
I was wearing shorts on the flight here and asked a couple of times if I'd be OK to go into the lounge with shorts. No issues I was told.

Though the welcome letter did state that flip flops and shorts were not allowed.

(Re Pullman CP: I've also seen people come in wearing their bath robes. I was one of their very frequent guests who complained about what some guests wore into the lounge - and one of the reasons why they became quite strict)