Subject: bug#66885: 29.1; gnus search with mu always returns empty

From: Eric Abrahamsen <[email-masked]>
Date: Thu, 02 Nov 2023 07:10:30 -0700

Britt Anderson <[email-masked]> writes:

> Copy and pasted the terminal output. mu is not expanding the 'tilde' in
> "--muhome", but if I use the full path, then I do get a list of files
> returned. However the error in the first form is not an empty search but
> a database detection error. 

That's fine, the value of config-directory is expand-file-name'd, so the
tilde doesn't make it through to mu.

Your problem is likely that your configuration doesn't include the
correct `remove-prefix', a string prefix that is removed from the
filenames returned by mu. The default is "~/Mail", which is wrong in
your case, it looks like it should be
"/home/britt/.local/share/mail/uwaterloo.ca/britt/archives".

That will have to go in your config. Note that search-engine
configuration options need to go inside the `gnus-search-engine' sexp --
your previous `config-directory' config was outside, at the `nnmaildir'
level. But that was the default value anyway, so you can leave it out.
This should be sufficient:

(setq gnus-secondary-select-methods
      '((nnmaildir "mail"
		   (directory "/home/britt/.local/share/mail")
		   (gnus-search-engine gnus-search-mu
                     (remove-prefix "/home/britt/.local/share/mail/uwaterloo.ca/britt/archives")))))

The "(gnus) Search Engines" info manual has more detail.