Issue #20454 has been updated by alanwu (Alan Wu). Status changed from Open to Third Party's Issue IRB has its own release cycles and bug tracker at https://github.com/ruby/irb/issues Sorry for the redirection, but please file this issue there. ---------------------------------------- Bug #20454: IRB echoes excessive input in dumb terminal https://bugs.ruby-lang.org/issues/20454#change-108150 * Author: zonuexe (Kenta USAMI) * Status: Third Party's Issue * ruby -v: ruby 3.3.1 (2024-04-23 revision c56cd86388) [arm64-darwin23] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- When IRB is started on a terminal with the environment variable TERM=dumb, excessive output is generated as shown below. A simple terminal such as Emacs shell-mode or comint-mode is assumed, but it should be possible to reproduce the following with a rich terminal such as iTerm. Type 1[RET], 12[RET], 123[RET] on your keyboard in this order. % TERM=dumb irb irb(main):001> 1 irb(main):001> 1=> 1 irb(main):002> 12 irb(main):002> 1irb(main):002> 12=> 12 irb(main):003> 123 irb(main):003> 1irb(main):003> 12irb(main):003> 123=> 123 As arton-san says, you can avoid the problem by not using ReadlineInputMethod. https://twitter.com/arton/status/1783008921000804630 -- https://bugs.ruby-lang.org/