bug#46271: 28.0.50; [PATCH] Properly quote group names for gnus-search

[Eric Abrahamsen]

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> jflack--- via "Bug reports for GNU Emacs, the Swiss army knife of text
> editors" <bug-gnu-emacs@gnu.org> writes:
>
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>> The new gnus-search-indexed-parse-output doesn't properly quote group
>> names before using them as regexes meaning a group name containing
>> meta-characters (other than . or \ because of the current replacement)
>> won't be properly matched in the search results later.
>>
>> I have attached a diff that fixes this by first quoting the group name
>> before performing the replacement; which is now constructed with RX
>> to save \\ soup.
>>
>> =2D-=20
>> Thanks,
>> Jai
>>
>> - --=-=-=
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>> Content-Disposition: attachment; filename=gnus-search-regex.diff
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>> diff --git a/lisp/gnus/gnus-search.el b/lisp/gnus/gnus-search.el
>> index 44f43b073c..54603d8792 100644
>> =2D-- a/lisp/gnus/gnus-search.el
>> +++ b/lisp/gnus/gnus-search.el
>> @@ -82,6 +82,7 @@
>>  (require 'gnus-util)
>>  (require 'eieio)
>>  (eval-when-compile (require 'cl-lib))
>> +(eval-when-compile (require 'rx))
>>  (autoload 'eieio-build-class-alist "eieio-opt")
>>  (autoload 'nnmaildir-base-name-to-article-number "nnmaildir")
>> =20
>> @@ -1380,8 +1381,8 @@ gnus-search-indexed-parse-output
>>                       (lambda (x)
>>                         (replace-regexp-in-string
>>                          ;; Accept any of [.\/] as path separators.
>> =2D                      "[.\\/]" "[.\\\\/]"
>> =2D                      (gnus-group-real-name x)))
>> +                        (rx (or "\\." "\\\\" "/")) "[.\\\\/]"
>> +                        (regexp-quote (gnus-group-real-name x))))
>>                       groups "\\|")))
>>      artlist vectors article group)
>>      (goto-char (point-min))
>
> Thanks very much for the patch! Let me do some local testing over the
> next couple of days, but at first glance this looks like it will do the
> trick.

Finally getting to this...

This doesn't quite do what it intends to do, as the
`replace-regexp-in-string' interferes with the `regexp-quote'. To wit:

(let ((group-name "mail+"))
  (replace-regexp-in-string
   "[.\\/]" "[.\\\\/]"
   (regexp-quote (gnus-group-real-name group-name))))
-> "mail[.\\/]+"

But what we wanted was:

"mail\\+"

So I think it has to get messier:

(let ((groups '("mail+" "gnus.gener+al" "archive.2007.10")))
  (mapconcat
   #'identity
   (mapcar
    (lambda (group-name)
      (mapconcat #'regexp-quote
                 (split-string
                  (gnus-group-real-name group-name)
                  "[.\\/]")
                 "[.\\\\/]"))
    groups)
   "\\|"))

-> "mail\\+\\|gnus[.\\\\/]gener\\+al\\|archive[.\\\\/]2007[.\\\\/]10"

This looks right to me. WDYT?

Also, I'd prefer not to use rx in this case, simply because this:

"[.\\/]"

turns into this:

(rx (or "\\." "\\\\" "/"))

Which seems like a loss of readability, though in general I think rx is
a very good idea.

Thanks again for the report!

Eric