Fix hscrolling with line numbers on TTY frames

* src/xdisp.c (hscroll_window_tree): Correct the X offset
calculations on TTY frames.
* src/term.c (produce_glyphs): Use it->lnum_pixel_width instead of
a kludge using it->lnum_width.

2 files changed, 14 insertions, 5 deletions

diff --git a/src/term.c b/src/term.c
index 46d8bff73cc..00a272c3b0b 100644
--- a/src/term.c
+++ b/src/term.c
@@ -1584,14 +1584,16 @@ produce_glyphs (struct it *it)
     {
       int absolute_x = (it->current_x
                         + it->continuation_lines_width);
-      /* Adjust for line numbers.  Kludge alert: the "2" below is
-         because we add 2 blanks to the actual line number.  */
+      int x0 = absolute_x;
+      /* Adjust for line numbers.  */
       if (!NILP (Vdisplay_line_numbers))
-        absolute_x -= it->lnum_width + 2 - it->w->hscroll;
+        absolute_x -= it->lnum_pixel_width;
       int next_tab_x
         = (((1 + absolute_x + it->tab_width - 1)
             / it->tab_width)
            * it->tab_width);
+      if (!NILP (Vdisplay_line_numbers))
+        next_tab_x += it->lnum_pixel_width;
       int nspaces;
 
       /* If part of the TAB has been displayed on the previous line
@@ -1599,7 +1601,7 @@ produce_glyphs (struct it *it)
          been incremented already by the part that fitted on the
          continued line.  So, we will get the right number of spaces
          here.  */
-      nspaces = next_tab_x - absolute_x;
+      nspaces = next_tab_x - x0;
 
       if (it->glyph_row)
         {
diff --git a/src/xdisp.c b/src/xdisp.c
index 3fc5f29d0c4..26b19eb44fb 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -13100,6 +13100,12 @@ hscroll_window_tree (Lisp_Object window)
                     }
                 }
             }
+          if (cursor_row->truncated_on_left_p)
+            {
+              /* On TTY frames, don't count the left truncation glyph.  */
+              struct frame *f = XFRAME (WINDOW_FRAME (w));
+              x_offset -= (FRAME_TERMCAP_P (f) || FRAME_MSDOS_P (f));
+            }
 
           text_area_width = window_box_width (w, TEXT_AREA);
 
@@ -28004,7 +28010,8 @@ x_produce_glyphs (struct it *it)
                 x -= it->lnum_pixel_width;
               int next_tab_x = ((1 + x + tab_width - 1) / tab_width) * tab_width;
               if (!NILP (Vdisplay_line_numbers))
-                next_tab_x += it->lnum_pixel_width;
+                next_tab_x += (it->lnum_pixel_width
+                               - it->w->hscroll * font->space_width);
 
               /* If the distance from the current position to the next tab
                  stop is less than a space character width, use the