Danny Siu <dsiu@adobe.com> writes:

> I have removed gnus-agent-fetch-selected-article from
> gnus-select-article-hook but the summary still highlights incorrectly the
> downloaded ones with gnus-summary-normal-undownloaded-face in few of my
> nnimap groups.  I tried removing the agent cache and gnus-agent-regenerate
> but that didn't help. 
>
> Attached screen shot.  here is my gnus-summary-line-format.
>
> (setq gnus-summary-line-format "%U%R%z%5N%O %(%8&user-date; %~(pad 2)~(max
> 2)~(ignore \"1\")t%[%5k:%* %-20,20n%] %B%s%)\n")
>
> where should i start debugging this problem?

Your screen shot shows that articles 17663 though 17718 have a (-)
undownloaded flag AND are highlighted with the
gnus-summary-normal-undownloaded-face.  Your format places the
download mark (+/-) AFTER the article number (the (+) before the
number is its score).

Please verify that these articles have been fetched into the agent by
excuting

M-: (assq 17663 gnus-agent-article-alist)

If it returns (17663), everything is working fine.  If it returns
(17663 . #) then I can't explain this.

As for debugging, I'd debug in gnus-summary-insert-line.

You should be able to trace though it's setting gnus-tmp-downloaded to
either 32 (no-mark), 43 (undownloaded), or 45 (downloaded).

I do have a patch for gnus-sum.  You should be able to use
gnus-agent-fetch-selected-article after installing it.