Fix pixel-scroll-precision-mode when point is on a blank line

[Stebalien]

When in the point is on a blank line in normal state, scrolling down with pixel-scroll-precision-mode enabled "sticks" because Evil ends up invoking line-move in the post-command-hook. line-move resets vscroll to 0, which undoes the scroll if we scrolled less than a line.

Specifically, evil-normal-post-command calls evil-adjust-cursor which calls evil-move-end-of-line which calls move-end-of-line, which finally calls line-move.

This change avoids this issue by avoiding evil-move-end-of-line entirely, instead using bolp to check if we're already at the beginning of the line.

(note: I'm not sure if there were subtle reasons for calling evil-move-end-of-line here)

Upstream bug report: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=72323. But Evil probably shouldn't be calling line-move here anyways.

[axelf4]

Thank you for looking into this. I cannot think of anything important the evil-move-end-of-line call is doing, with the preceding (eolp) check (added by commit 907e7aa).

See: #1778

On a broader note, why does save-excursion not restore vscroll? Would that not alleviate this particular issue?

[Stebalien]

On a broader note, why does save-excursion not restore vscroll? Would that not alleviate this particular issue?

save-excursion doesn't affect scrolling, just point. E.g., (save-excursion (set-window-start nil 0) will scroll to the top of the buffer, leaving point where it was.