Habitat: studio terminal bug in 0.12.0

[juliandunn]

It looks like we have a studio terminal handling bug inside of 0.12.0 studios. On 0.11.0, if you enter a studio and try to backspace after typing things, it worked. Now, trying to backspace instead adds an additional space to the input.

Additionally, if you try to run reset to reset your terminal, you get the following error:

reset: can't initialize terminal type xterm (error -1)
Terminal type?

(with an interactive prompt)

I'm suspecting the bug is related to #1318. The studio is correctly built with core/ncurses inside it, but there is no such directory /hab/pkgs/core/ncurses/6.0/20161031042533/share/terminfo.

[juliandunn]

A workaround is to install the older version of core/ncurses and set the TERMINFO database to it.

hab pkg install core/ncurses/6.0/20160612075116
export TERMINFO=/hab/pkgs/core/ncurses/6.0/20160612075116/share/terminfo

[fnichol]

Okay, it turns out that having a TERMINFO environment variable set affects the build of core/ncurses without changing the plan at all--cool no?

Rather than re-evaluating #1318 I think our way out is to explicitly unset TERMINFO in the build program to guarantee that this userland convenience never leaks into a plan build. I'm not entirely sure what other software or autoconf tooling might do with this environment variable but would rather provide as minimalistic a starting point as possible with respect to environment variables.

I'll have a PR shortly to the Studio codebase to unset this variable which is the code fix, but we'll want to rebuild ncurses so that it contains the terminfo database entries as before. Good thing is: I'm pretty fresh on this activity 😉

[juliandunn]

fixed in #1440