Not sure if this is a bug, but . . .
Game had Charm, and 4 different 6-value cards (Gold, Farmland, Harem, and Nobles).
I had a hand with 6 coins and 2 Charms. My thought was. (a) Use the 6 coins to buy Gold, and then Charm, to get a Gold a Nobles. Then, use the 2nd Charm to try to do the same exact thing...to gain a 3rd card. My hope would be to get another Nobles--as it would still not be the "named" card. But one of the other two still-not-yet-gained-this-turn cards would have been okay.
Tried (via 'Undo') several times, but could not get "Gain equal-value card" more than once per turn. Once I selected "gain card", the game's AI automatically stopped me from putting down any other Treasure...including, of course, that 2nd Charm. Only way to play a second Charm was to select--with my first Charm--the "Buy + 2 coins" option. The only thing that Charm says is "next time you buy a card...". So, nothing there about "only once per turn" or any other limiting factor. Hmmm.
What would have happened if I had had 2 buys and 12 coins in play, instead of only 6? Would the game's AI have recognized that I now had enough coins to play 6+ Charm, and then 6+ Charm? My guess is no.
Is this a bug? Or some subtlety that is whooshing over my head???