Typo in doc string of `gnus-dependencies-add-header'?

[N. Jackson]

In Gnus v5.13 in GNU Emacs 27.0.50
Repository revision: f3f67cf0b9a6388d423e048a7aafad2eb531b5a5


While poking around [1] in the code, I stumbled across something in
`gnus-dependencies-add-header' that confused me. If I understand
correctly, there is typo in the doc string.

The paragraph in question says:

  If `gnus-summary-ignore-duplicates' is nil then duplicate
                                      ^^^^^^   
  Message-IDs will not be entered in the DEPENDENCIES table.
  Otherwise duplicate Message-IDs will be renamed to a unique
  Message-ID before being entered.

but it seems to me that this should begin:

  If `gnus-summary-ignore-duplicates' is not nil ...

.

The relevant code seems to be in the `cond' in
`gnus-dependencies-add-header' at Line 4323 of gnus-sum.el:

    (cond
    ...
     ;; Renames the existing `header' to a unique Message-ID.
     ((not gnus-summary-ignore-duplicates)
      ;; An article with this Message-ID has already been seen.
      ;; We rename the Message-ID.
      (set (setq id-dep (intern (setq id (nnmail-message-id)) dependencies))
           (list header))
      (mail-header-set-id header id))
    ...
    )

Am I right that the doc string is wrong, or am I missing something?

(I could easily be missing something: trying to read Lisp makes my
head hurt! (The world would be so much kinder on my noggin if
everything were written in C.))

Thanks.

N.


[1] I'm trying to get a better understanding of Bug#28477
(https://debbugs.gnu.org/cgi/bugreport.cgi?bug=28477) where Gnus
occasionally gets the order wrong when displaying threads (and
will show message A as reply to message B when in fact message B
was the later message and responds to message A).