From 6f23291b8d3e9880536f968621cc52d180f09ddc Mon Sep 17 00:00:00 2001
From: VVKot <volodymyr.kot.ua@gmail.com>
Date: Sun, 31 Jan 2021 17:53:52 +0000
Subject: vim-patch:8.1.0154: crash with "set smarttab shiftwidth=0
 softtabstop=-1"

Problem:    Crash with "set smarttab shiftwidth=0 softtabstop=-1".
Solution:   Fall back to using 'tabstop'. (closes vim/vim#3155)
https://github.com/vim/vim/commit/c9fe5ab3b093803b6e8d03358ba16aca6b6f0db1
---
 src/nvim/edit.c               |  6 ++++--
 src/nvim/testdir/test_tab.vim | 11 ++++++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

(limited to 'src')

diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index 31bb00a746..90b5cfd8aa 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -8189,6 +8189,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
                 && (*(get_cursor_pos_ptr() - 1) == TAB
                     || (*(get_cursor_pos_ptr() - 1) == ' '
                         && (!*inserted_space_p || arrow_used)))))) {
+      int ts;
       colnr_T vcol;
       colnr_T want_vcol;
       colnr_T start_vcol;
@@ -8203,7 +8204,8 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
       getvcol(curwin, &curwin->w_cursor, NULL, NULL, &want_vcol);
       inc_cursor();
       if (p_sta && in_indent) {
-        want_vcol = (want_vcol / curbuf->b_p_sw) * curbuf->b_p_sw;
+        ts = (int)get_sw_value(curbuf);
+        want_vcol = (want_vcol / ts) * ts;
       } else {
         want_vcol = tabstop_start(want_vcol,
                                   get_sts_value(),
@@ -8700,7 +8702,7 @@ static bool ins_tab(void)
   AppendToRedobuff("\t");
 
   if (p_sta && ind) {  // insert tab in indent, use 'shiftwidth'
-    temp = (int)curbuf->b_p_sw;
+    temp = (int)get_sw_value(curbuf);
     temp -= get_nolist_virtcol() % temp;
   } else if (tabstop_count(curbuf->b_p_vsts_array) > 0
              || curbuf->b_p_sts != 0) {
diff --git a/src/nvim/testdir/test_tab.vim b/src/nvim/testdir/test_tab.vim
index 3be30245b9..b8e8dfe062 100644
--- a/src/nvim/testdir/test_tab.vim
+++ b/src/nvim/testdir/test_tab.vim
@@ -76,6 +76,15 @@ func Test_softtabstop()
   exe "normal A\<BS>x\<Esc>"
   call assert_equal("x   x", getline(1))
 
-  set sts=0 sw=0 backspace&
+  call setline(1, 'x')
+  set sts=-1 sw=0 smarttab
+  exe "normal I\<Tab>\<Esc>"
+  call assert_equal("\tx", getline(1))
+
+  call setline(1, 'x')
+  exe "normal I\<Tab>\<BS>\<Esc>"
+  call assert_equal("x", getline(1))
+
+  set sts=0 sw=0 backspace& nosmarttab
   bwipe!
 endfunc
-- 
cgit