They laughed. Apparently picking up Spanish from your Spaniard friend has some downsides.
As in South American backpackers find it funny/amusing this drunk Chinese guy in an Australian pub used the Castellano equivalent of "y'all" in a sentence.
They were ultimately nice about it, much better than the time my (English speaking) Canadian coworker tried to speak to some Parisians in school level Québécois and they scoffed and continued in English.
It is which, just exposes that the continental attitude to other french dialects is based on chauvinism
Plus, let alone ask a French person where are the Occitan native speakers in his country...
The French Revolution may have done a lot of things right but creating a central, unified state, at the expense of bringing many local languages into near-extinction, is not one of them...