lukeworth@Lukes-MBP /tmp> function show_prompt_details --on-event fish_prompt
      echo fish_prompt received!
  end
fish_prompt received!
lukeworth@Lukes-MBP /tmp> cd a
fish_prompt received!
lukeworth@Lukes-MBP /t/a> prevd
fish_prompt received!
lukeworth@Lukes-MBP /tmp> cdh
 a  1)  /tmp/a
fish_prompt received!
fish_prompt received!
Select directory by letter or number:

This is particularly annoying because I was using the fish_prompt event to display a wrappable environment status (c.f. #904 (comment)).

As a workaround I am using the fish_postexec event. (Um, if anyone's using vim and this starts breaking plugins, try :set shell=sh to force POSIX shell instead of fish. TIL)

Environment

[I] ➜ echo $version
3.1.2
[I] ➜ uname -a
Darwin Lukes-MBP 19.4.0 Darwin Kernel Version 19.4.0: Wed Mar  4 22:28:40 PST 2020; root:xnu-6153.101.6~15/RELEASE_X86_64 x86_64 i386 MacBookPro11,5 Darwin
[I] ➜ echo $TERM
xterm-256color