• fish, version 3.6.1
• macOS Ventura 13.5
• iTerm 2: Build 3.4.21
• Running sh -c 'env HOME=$(mktemp -d) XDG_CONFIG_HOME= fish' doesn't affect anything

I've been playing around with the history delete function a bit, and discovered something surprising: if I use --exact --case-sensitive, changes don't propagate to the fish_history until after I run another command. It's possible that I'm doing something wrong, but I think what I'm doing is pretty reasonable.

If a user tries to delete a command from history with --exact --case-sensitive and then closes their session, the deletion will not be saved to their fish_history file.

Steps to reproduce

1. Open a new shell session

2. Run the following lines, which run a command and then delete it from history:

   $ echo "my password is hunter2"
   $ history delete --exact --case-sensitive 'echo "my password is hunter2"'

3. Close the session

4. Open a new shell session

5. Type echo

I expect that fish won't suggest the echo "my password is hunter2" command, because I've deleted it from the history. But what actually happens is that it gets suggested!

Observations

• This doesn't reproduce if I run an extra command between steps 3 and 4. This command doesn't have to do anything interesting – true is plenty.

• I can reproduce if I use builtin history delete instead of history delete.

• This doesn't reproduce if I search the history to delete the offending command. Something like:

  $ echo "my password is hunter2"
  my password is hunter2
  
  $ history delete
  Search term: hunter2
  [1] echo "my password is hunter2"
  [2] history delete --exact --case-sensitive 'echo "my password is hunter2"'
  
  Enter nothing to cancel the delete, or
  Enter one or more of the entry IDs separated by a space, or
  Enter "all" to delete all the matching entries.
  
  Delete which entries? > 1
  
  Deleting history entry 1: "echo "my password is hunter2""

  If I start typing echo in a new command, I don't get the offending command suggested.

• As far as I can tell, the change doesn't seem to be making it to my fish_history file until after I run the next command. Let's step through it in a clean session with sh -c 'env HOME=$(mktemp -d) XDG_CONFIG_HOME= fish':

  1. First I’ll open the fish_history file in an external editor, so I can see what it looks like after each command:

     $ mate "$HOME/.local/share/fish/fish_history"

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697835968

  2. Run the echo command:

     $ echo "my password is hunter2"

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697835968
     - cmd: echo "my password is hunter2"
       when: 1697835997

  3. Try to delete that last command from history:

     $ history delete --exact --case-sensitive 'echo "my password is hunter2"'

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697835968
     - cmd: echo "my password is hunter2"
       when: 1697835997
     - cmd: history delete --exact --case-sensitive 'echo "my password is hunter2"'
       when: 1697836030

     Notice that both the deleted command and the history delete command are still in the history.

     If I close my session here, the supposedly deleted command will persist.

  4. Now run any other command:

     $ true

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697835968
     - cmd: history delete --exact --case-sensitive 'echo "my password is hunter2"'
       when: 1697836030
     - cmd: true
       when: 1697836073

     Notice that the command I tried to delete in step iii has now been purged from the history.

• For comparison, here's what happens if I do an interactive search for items to delete, as before in a new shell:

  1. Open the fish_history file in an external editor:

     $ mate "$HOME/.local/share/fish/fish_history"

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697836363

  2. Run the echo command:

     $ echo "my password is hunter2"

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697836363
     - cmd: echo "my password is hunter2"
       when: 1697836376

  3. Run history delete with a search query of hunter2, and ask it to delete the single item which it finds:

     $ history delete
     Search term: hunter2
     [1] echo "my password is hunter2"
     
     Enter nothing to cancel the delete, or
     Enter one or more of the entry IDs separated by a space, or
     Enter "all" to delete all the matching entries.
     
     Delete which entries? > 1
     
     Deleting history entry 1: "echo "my password is hunter2"

     - cmd: mate "$HOME/.local/share/fish/fish_history"
       when: 1697836363
     - cmd: history delete
       when: 1697836403

     Notice that the offending command has already been scrubbed from the history.