Mixed-operator lists aren't fully line-broken

[ag-eitilt]

Lists which are constructed using only , or only ++ are both rendered correctly, but lists which contain some number of single items followed by two or more concatenated lists aren't properly broken:

def list =
    first,
    second,
    severalItems ++ severalMoreItems

Attaching @V-FEXrt's analysis from the internal issue spawning this:

Yeah I think this is a weird (but expected) interaction of not exploding binops when they are nested inside other binops.

In this case it seems like the ++s are inside of a binop(COMMA, lhs, ADD)