I have what might be a newbie question but I need to explain the turn first that led up to it, I was playing a 2-player game with my brother.
First I played a Throne Room, and a Cellar. Then I took my two cellar actions -- the first one was an Embargo. I chose the money option for the Embargo and took my two coppers into my hand, and then the other action was a Woodcutter. (I was going to play my Thief but I couldn't since my brother's deck was empty. Anyway I'm sure he had a secret chamber to block the attack.) I used the Woodcutter buy to get a curse (which I put in my brother's discard pile) and then took a silver for the money part. Back to the TR'd cellar, I discarded 3 cards and picked up 6. Then for my buy phase I had 10 money in my hand so I discarded the treasures, bought a province, and remembered that I would have 2 extra money next turn.
When I discarded the rest of the cards I picked up my 5 card hand for next round. One was a mining village which I was immediately able to trash for a silver, but then I had to discard one card to get down to 5.
Now it was my brother's turn. He bought the last province and I wondered, does he get to finish his turn or does the game end immediately?
I should have also had trashing 2 treasure maps from hand without using an action...