vim-patch:8.0.0669: CTRL-N at start of the buffer does not work correctly (#8600)

Problem:    In Insert mode, CTRL-N at start of the buffer does not work
            correctly. (zuloloxi)
Solution:   Wrap around the start of the buffer. (Christian Brabandt)
https://github.com/vim/vim/commit/24a9e348aa88a6c60ae0cdf5c4a777d8c03b08ca

1 files changed, 9 insertions, 3 deletions

diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index 1f18fc36fd..d4075fc197 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -3708,9 +3708,15 @@ static int ins_compl_get_exp(pos_T *ini)
       if (*e_cpt == '.' && !curbuf->b_scanned) {
         ins_buf = curbuf;
         first_match_pos = *ini;
-        /* So that ^N can match word immediately after cursor */
-        if (l_ctrl_x_mode == 0)
-          dec(&first_match_pos);
+        // Move the cursor back one character so that ^N can match the
+        // word immediately after the cursor.
+        if (ctrl_x_mode == 0 && dec(&first_match_pos) < 0) {
+          // Move the cursor to after the last character in the
+          // buffer, so that word at start of buffer is found
+          // correctly.
+          first_match_pos.lnum = ins_buf->b_ml.ml_line_count;
+          first_match_pos.col = (colnr_T)STRLEN(ml_get(first_match_pos.lnum));
+        }
         last_match_pos = first_match_pos;
         type = 0;