Not dream of something/of doing something - Idioms by The Free Dictionary
not dream of something/of doing something
wouldn't dream of (doing something)
Wouldn't even consider doing something in particular (stated after "of"). I'm sure Mom didn't read that letter you got—she wouldn't dream of opening someone else's mail.
not ˈdream of something/of doing something (often used with would) not even consider something under any circumstances: ‘Don’t tell Gary what I’ve bought him for his birthday.’ ‘I wouldn’t dream of it.’ ♢ Only a couple of years ago he would never have dreamt of going abroad on his own, and now he’s travelling around India!