Re: Re-reading history from ZLE

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

On Wed, Aug 24, 2022 at 8:26 AM martin f krafft <madduck@xxxxxxxxxxx> wrote:
>
> Is there a reason why reset-prompt shouldn't re-initialise ZLE's understanding of history?

History isn't updated until ZLE exits (accept-line, etc.).  The
"current event" is not actually in the history, it's treated specially
as a pending entry; almost anything you do with a widget (including
print -s) is effectively part of that pending entry.

There is one exception:  The "fc" command updates the history
immediately.  So if you rewrite your widget as ...

_test_hist() {
    fc -R =(<<<"echo foo")
    zle -M "The last line of history is now 'echo foo'
    zle reset-prompt
  }

... then you'll get what you want, including seeing the value of %h
(history number) in your prompt increase by one.

Beware that "fc -R" may ignore lines beginning with ": " because it's
attempting to intuit whether the file is using extended history
format, and if you're adding a multi-line entry you'll want to prefix
all the newlines with backslashes, etc.