Question

I am getting problem with autoscrolling with next-line in emacs. When i get to the edge of the screen
https://i.stack.imgur.com/lfqEL.png
and making next-line sometimes I am not scrolled, and pointer aims to the center of the CURRENT screen, not the NEXT screen. https://i.stack.imgur.com/FPbuC.png
(so if i hold C-n pointer will run endlessly through this screen)

I am getting same things with forward-line, sometimes with forward-page. I am not getting the same with previous-line autoscrolling, it works fine.

I don’t know why. I only noticed, that when I have more long lines, and screen is splited vertically, this thing happens very fast(C-x 3 C-x 3, scrolling from the beginning of my 1000-lines .emasc file is a fast way to reproduce this bug).

Emacs -Q, (setq truncate-lines nil) doesn’t have it. Emacs, (setq truncate-lines t) doesn’t have it too.

If you know anything about what can cause this troubles, please reply.

Answer 1

After 2-hour using eval-region (this problem wasn’t easy to reproduce, macro/elisp with (next-line) (sit-for 0.01) didn’t give any effect, so I tested it each time by holding C-n, using binary search method for eval-region)

So the answer is:

http://www.emacswiki.org/emacs/HighlightParentheses

Evaluating this in a *scratch*, starting emacs with emacs -Q

(setq-default truncate-lines nil)
(setq truncate-partial-width-windows nil)
(add-to-list 'load-path "~/my_path_to_highlight-parentheses_script/")
(require 'highlight-parentheses)

Make some buffer with long lines and narrow it with C-x 3 C-u 5 0 C-x } then C-x o M-x highlight-parentheses-mode and hold C-n is a way to reproduce the bug.

I commented out all thing relative with highlight-parentheses, and bug gone away. I think, I should find a way to tell developers about this bug.