Subject: bug#75690: 30.0.93; completion-preview-mode doesn't work with dabbrev-capf

From: Eshel Yaron <[email-masked]>
Date: Sat, 01 Mar 2025 08:30:40 +0100

Hi there,

[email-masked] writes:

> Steps to reproduce with 'emacs -Q':
> 0. Switch to scratch buffer
>
>    (scratch-buffer)
>
> 1. Enable completion preview mode:
>
>    (global-completion-preview-mode)
>
> 2. add dabbrev-capf
>
>    (push
>     'dabbrev-capf completion-at-point-functions)
>
> 3. test
>
>    ;; Emacs
>    ;; Ema
>
> Get the follow error:
>
>    Error in post-command-hook (completion-preview--post-command):
> (user-error "No dynamic expansion for \"Ema\" found")

Thanks for the report, and apologizes for the late response.  It seems
like your message never made it to the mailing list.

Anyway, AFAICT this is a duplicate of Bug#61274, it's a problem in
dabbrev-capf, unrelated to completion-preview-mode per se.

You can use cape-dabbrev from the GNU ELPA package cape as a workaround.

Best regards,

Eshel