From: Eli Zaretskii <eliz@gnu.org>
Date: Fri, 6 Aug 2021 07:51:45 +0000 (+0300)
Subject: Fix automatic hscrolling when line numbers are displayed
X-Git-Tag: emacs-28.0.90~1591^2~15
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=4d6511a2842ee92271b0ddc4572cb2a801a172a5;p=emacs.git

Fix automatic hscrolling when line numbers are displayed

* src/xdisp.c (hscroll_window_tree): When line numbers are
displayed, account for the the line-number space when calculating
the desired X coordinate on the left.  (Bug#49891)
---

diff --git a/src/xdisp.c b/src/xdisp.c
index 70d15aee68c..e62f7e3df6e 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -15082,11 +15082,12 @@ hscroll_window_tree (Lisp_Object window)
 	      else
 		{
 		  if (hscroll_relative_p)
-		    wanted_x = text_area_width * hscroll_step_rel
-		      	       + h_margin;
+		    wanted_x =
+		      text_area_width * hscroll_step_rel + h_margin + x_offset;
 		  else
-		    wanted_x = hscroll_step_abs * FRAME_COLUMN_WIDTH (it.f)
-		      	       + h_margin;
+		    wanted_x =
+		      hscroll_step_abs * FRAME_COLUMN_WIDTH (it.f)
+		      + h_margin + x_offset;
 		  hscroll
 		    = max (0, it.current_x - wanted_x) / FRAME_COLUMN_WIDTH (it.f);
 		}