fix(ui): cursor pos with left gravity inline virt_text at eol (#24329)

Problem:    Cursor is not after inline virtual text with left gravity
            when inserting after the end of the line.
Solution:   Add width of inline virtual text with left gravity to cursor
            virtcol in Insert mode even if on a NUL.

1 files changed, 4 insertions, 5 deletions

diff --git a/src/nvim/charset.c b/src/nvim/charset.c
index c2745a66a0..c6efb4b3b4 100644
--- a/src/nvim/charset.c
+++ b/src/nvim/charset.c
@@ -1089,12 +1089,11 @@ void getvcol(win_T *wp, pos_T *pos, colnr_T *start, colnr_T *cursor, colnr_T *en
       // cursor at end
       *cursor = vcol + incr - 1;
     } else {
-      if (!on_NUL) {
-        // cursor is after inserted text, unless on the NUL
+      if (!on_NUL || !(State & MODE_NORMAL)) {
         vcol += cts.cts_cur_text_width_left;
-        if ((State & MODE_INSERT) == 0) {
-          vcol += cts.cts_cur_text_width_right;
-        }
+      }
+      if (!on_NUL && (State & MODE_NORMAL)) {
+        vcol += cts.cts_cur_text_width_right;
       }
       // cursor at start
       *cursor = vcol + head;