Bug #17680: tab completion no longer works on irb3.0

• Status: Open
• Priority: Normal
• Assignee: -
• Target version: -
• ruby -v: ruby 3.0.0p0 (2020-12-25 revision 95aff21468) [x86_64-darwin16]
• Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

[simondedeo (Simon DeDeo)]

in irb2.5:

rb(main):001:0> source 'li [then I hit tab...]
linking.rb list_load.rb list_load_OLD.rb
irb(main):001:0> source 'lis [then I hit tab again...]
list_load.rb list_load_OLD.rb
irb(main):001:0> source 'list_load.rb' [then I hit tab again...]

in irb3.0, hitting tab after typing "source 'li" gives.

irb(main):001:0' source 'li'

Here are my version numbers:

ayerie:simon$ irb3.0 -v
irb 1.3.0 (2020-12-25)
ayerie:CHLOE simon$ ruby3.0 -v
ruby 3.0.0p0 (2020-12-25 revision 95aff21468) [x86_64-darwin16]
ayerie:simon$

[crocarneiro (Carlos Carneiro)]

I could not reproduce the old version behaviour. I got back to irb 1.1.0 and the autocomplete behaviour is the same as the version 1.3.4. My steps:

$ touch linking.rb
$ touch list_load.rb
$ touch list_load_OLD.rb
$ irb
2.5.0 :001 > source 'li

Hitting tab gives me:
2.5.0 :001 > source 'li'

irb -v: irb 1.1.0 (2019-11-21)
ruby -v: ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-linux]
OS: Ubuntu 20.04.1 LTS

How you achieved that behaviour in the old version? How was your "~/.irbrc" file?

[xtkoba (Tee KOBAYASHI)]

What is confusing is that the behavior of IRB changes drastically with readline.so. I suppose that Ruby 2.5 of the main issue is the case when readline.so is installed, and that the rest (Ruby 3.0 of the main issue and Ruby 2.5 of #note-1) are when it is not installed.

My observation is as follows. For Ruby 2.5.8:

/$ ruby --version
ruby 2.5.8p224 (2020-03-31 revision 67882) [x86_64-linux]

/$ irb --version
irb 0.9.6(09/06/30)

/$ [Make sure that readline.so exists]

/$ irb
irb(main):001:0> "[Press Tab twice]
bin/   dev/   home/  lib64/ mnt/   proc/  run/   sys/   usr/
boot/  etc/   lib/   media/ opt/   root/  sbin/  tmp/   var/

[Terminate IRB]

/$ [Remove readline.so]

/$ irb
irb(main):001:0> "[Press Tab here, and ...]
irb(main):001:0> "      [<- "\t" is shown]

For Ruby 2.7.2:

/$ ruby --version
ruby 2.7.2p137 (2020-10-01 revision 5445e04352) [x86_64-linux]

/$ irb --version
irb 1.2.6 (2020-09-14)

/$ [Make sure that readline.so exists]

/$ irb
irb(main):001:0> "[Nothing happens when Tab is pressed many times]

[Terminate IRB]

/$ [Remove readline.so]

/$ irb
irb(main):001:0> "[Press Tab here, and ...]
irb(main):001:0> ""

As you can see above, there are four patterns of Tab behavior depending on the version of IRB/Ruby and the existence of readline.so.