What happened when Italy attacked France before they surrendered to the Germans and just how successful/unsuccessful were they in their attacks?

I have been told before that after the Italians finally joined in on the war against France they attacked across Frances South-east border with overwhelming numbers and failed horrifically. This leading to the only major condition of the French surrender to the Germans was that Italy could not take any French land. What is the truth to this if any? Did my teacher lie to me with an interesting sounding “fact”?