Don't enable test mode by TERM=dumb #660

Activity

1. tompng

   changed the title [-]Enable test mode not by TERM=dumb[/-] [+]Don't enable test mode by TERM=dumb[/+] on Mar 23, 2024
2. st0012 commented on Mar 23, 2024

   

   st0012

   on Mar 23, 2024

   Member

   More actions

   I haven't looked much into the issue yet, but we need to be very cautious about this change because many projects, like Rails and debug, use TERM=dumb to turn on the Reline test mode. If we did decide to implement this change, let's make sure we roll it out gradually (e.g. supporting both TERM=dumb and the alternative for a while) so we have time to help those projects updating their tests.

   👍React with 👍1Reacted by tomoya ishida
3. dgutov commented on Mar 23, 2024

   

   dgutov

   on Mar 23, 2024

   More actions

   FWIW, if we're talking about Reline inside Emacs, then removing special handling for TERM=dumb is not enough: if I just change those checks, that brings back the ▽ problem.
4. tompng commented on Mar 24, 2024

   

   tompng

   on Mar 24, 2024

   MemberAuthor

   More actions

   If we're doing this, we also need to disable ▽ and "\e[6n" (Query Cursor Position) if TERM=dumb.

   👍React with 👍2Reacted by Dmitry Gutov and Stéphane Maniaci
5. eregon commented on Mar 7, 2026

   

   eregon

   on Mar 7, 2026

   Last edited by eregon

   Member

   More actions

   like Rails and debug, use TERM=dumb to turn on the Reline test mode.

   I'm surprised by this, does anyone using Rails or the debug gem really want the Reline test mode?
   It outputs a lot of extra output which seems unusable except maybe when debugging Reline itself:

   $ echo 'my input' > in
   $ TERM=dumb ruby -rreadline -e 'p Readline; p [STDIN,STDOUT,STDERR].map(&:tty?); p Readline.readline("> ", true)' < in |& ruby -e 'p STDIN.read' 
   "Reline\n[false, false, false]\n> > mmymy my imy inmy inpmy inpumy input> my input\r\n\"my input\"\n"
   

   (context: #886)
6. st0012 commented on Mar 9, 2026

   

   st0012

   on Mar 9, 2026

   Member

   More actions

   It's used in those projects to run integration tests that can verify the console's outupt. Not by their users.
7. eregon commented on Mar 9, 2026

   

   eregon

   on Mar 9, 2026

   Member

   More actions

   Would you have an example?
   I find it unlikely that some test would check e.g. that my input results in mmymy my imy inmy inpmy inpumy input or so.

   I'd expect tests would use TERM=dumb to avoid extra escape sequences from Reline (#886), but then (non-reline-internal) tests would also expect no extra prints like mmymy my imy inmy inpmy inpumy input.
8. eregon commented on Mar 9, 2026

   

   eregon

   on Mar 9, 2026

   Last edited by eregon

   Member

   More actions

   Reline test mode

   What does that do?
   I think it's most people expectation that TERM=dumb means no extra escape sequences, and also that it behaves like a dumb terminal so e.g. echo'es the input as-is or with minimal changes, and without what looks like reline debugging output or so.

   IOW, I doubt that disabling the mmymy my imy inmy inpmy inpumy input debugging would break any non-reline-internal test.
   And that the original issue seems worth solving and seems not so likely to break anything.
9. st0012 commented on Mar 9, 2026

   

   st0012

   on Mar 9, 2026

   Member

   More actions

   https://github.com/rails/rails/blob/7ff005d9416388f0fa6d89895c4c560c13717164/railties/test/engine/commands_test.rb#L40

   The goal is to just capture input for testing. But unfortunately we have to print every character too.