From: Eli Zaretskii <eliz@gnu.org>
To: Keith David Bershatsky <esq@lawlist.com>
Cc: 28936@debbugs.gnu.org
Subject: bug#28936: move_it_in_display_line_to returns MOVE_POS_MATCH_OR_ZV before ZV
Date: Sun, 22 Oct 2017 21:30:45 +0300 [thread overview]
Message-ID: <83zi8j9gru.fsf@gnu.org> (raw)
In-Reply-To: <m2shebgirq.wl%esq@lawlist.com> (message from Keith David Bershatsky on Sun, 22 Oct 2017 11:05:45 -0700)
> Date: Sun, 22 Oct 2017 11:05:45 -0700
> From: Keith David Bershatsky <esq@lawlist.com>
> Cc: 28936@debbugs.gnu.org
>
> Thank you, Eli, for looking into #28936.
I don't think there's any bug here.
> With respect to `move_it_in_display_line`, I was not able to reliably land on `it.first_visible_x + lnum_pixel_width` when horizontal scrolling to the right AND text truncated on the left. IT overshoots the target by one text character.
This means you have an off-by-one error, probably because you are
not computing the target X coordinate correctly. The mistake I show
below is probably the same mistake you do elsewhere.
> while (it->current_x + it->pixel_width <= target_x
This condition will cause the iterator to attempt to get to the
character _after_ point, where it will hit ZV. So what you see, viz.:
> STEP #5: Observe that the result is "1" when it should be "2".
is expected. You should change the condition to this:
while (it->current_x < target_x
next prev parent reply other threads:[~2017-10-22 18:30 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-22 3:02 bug#28936: move_it_in_display_line_to returns MOVE_POS_MATCH_OR_ZV before ZV Keith David Bershatsky
2017-10-22 5:14 ` Keith David Bershatsky
2017-10-22 14:12 ` Eli Zaretskii
2017-10-22 14:10 ` Eli Zaretskii
2017-10-22 18:05 ` Keith David Bershatsky
2017-10-22 18:30 ` Eli Zaretskii [this message]
2017-10-22 19:53 ` Eli Zaretskii
2017-10-22 19:22 ` bug#28936: nRe: " Keith David Bershatsky
2017-10-22 19:41 ` Eli Zaretskii
2017-10-23 5:20 ` Keith David Bershatsky
2017-10-23 13:55 ` Eli Zaretskii
2017-10-25 3:46 ` bug#28936: enhancement request: remove vertical scroll bar automatically when not needed Keith David Bershatsky
2017-10-25 5:30 ` Keith David Bershatsky
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