Investigate login -pfq $USER $COMMAND for custom commands. [was: screen width doesn't seem to get propagated right?]
How to reproduce:
Create an alias to bash, ex: /bin/bash_iterm Preferences menu -> Profiles -> General -> Command (command): /bin/bash_iterm (I use something like this to speedup intial tab open time)
create two tabs, then in the left one run vi
change to right tab
make the window "wider"
change to left tab, exit vi
try to type a "long command." Watch bash in left tab write "long commands" all on the same line (as if the absence of new line). This is the weirdness here.
Resize window
Now bash in left tab works like normal no more weirdness.
Terminal (the built in app) seems to do this OK...
stty looks like it has the right values the whole time.