vim-patch:8.1.2172: spell highlight is wrong at start of the line

Problem:    Spell highlight is wrong at start of the line.
Solution:   Fix setting the "v" variable. (closes vim/vim#5078)
https://github.com/vim/vim/commit/7751d1d1a3d447d0d48f57f34e0da9f7c6ac433d

Skip spell tests in OpenBSD.

Nvim or screen likely crashed.
Revist once issue #12104 is fixed.
Skip the test for the following reasons:
- unknown regression caused by https://github.com/neovim/neovim/issues/12104
- cannot revert failing test from https://github.com/neovim/neovim/commit/ed0d135247790f67ead7f1a8c21a020790e80a74

3 files changed, 53 insertions, 0 deletions

diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 7bed747e9a..6f122442c4 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -3476,6 +3476,7 @@ win_line (
          * Only do this when there is no syntax highlighting, the
          * @Spell cluster is not used or the current syntax item
          * contains the @Spell cluster. */
+        v = (long)(ptr - line);
         if (has_spell && v >= word_end && v > cur_checked_col) {
           spell_attr = 0;
           if (!attr_pri) {
diff --git a/src/nvim/testdir/check.vim b/src/nvim/testdir/check.vim
new file mode 100644
index 0000000000..57a8eb57b8
--- /dev/null
+++ b/src/nvim/testdir/check.vim
@@ -0,0 +1,11 @@
+source shared.vim
+source term_util.vim
+
+" Command to check that making screendumps is supported.
+" Caller must source screendump.vim
+command CheckScreendump call CheckScreendump()
+func CheckScreendump()
+  if !CanRunVimInTerminal()
+    throw 'Skipped: cannot make screendumps'
+  endif
+endfunc
diff --git a/src/nvim/testdir/test_spell.vim b/src/nvim/testdir/test_spell.vim
index e5eaa01e92..414c7278eb 100644
--- a/src/nvim/testdir/test_spell.vim
+++ b/src/nvim/testdir/test_spell.vim
@@ -1,10 +1,13 @@
 " Test spell checking
 " Note: this file uses latin1 encoding, but is used with utf-8 encoding.
 
+source check.vim
 if !has('spell')
   finish
 endif
 
+source screendump.vim
+
 func TearDown()
   set nospell
   call delete('Xtest.aff')
@@ -477,6 +480,44 @@ func RunGoodBad(good, bad, expected_words, expected_bad_words)
   bwipe!
 endfunc
 
+func Test_spell_screendump()
+  CheckScreendump
+
+  let lines =<< trim END
+       call setline(1, [
+             \ "This is some text without any spell errors.  Everything",
+             \ "should just be black, nothing wrong here.",
+             \ "",
+             \ "This line has a sepll error. and missing caps.",
+             \ "And and this is the the duplication.",
+             \ "with missing caps here.",
+             \ ])
+       set spell spelllang=en_nz
+  END
+  call writefile(lines, 'XtestSpell')
+  let buf = RunVimInTerminal('-S XtestSpell', {'rows': 8})
+  call VerifyScreenDump(buf, 'Test_spell_1', {})
+
+  let lines =<< trim END
+       call setline(1, [
+             \ "This is some text without any spell errors.  Everything",
+             \ "should just be black, nothing wrong here.",
+             \ "",
+             \ "This line has a sepll error. and missing caps.",
+             \ "And and this is the the duplication.",
+             \ "with missing caps here.",
+             \ ])
+       set spell spelllang=en_nz
+  END
+  call writefile(lines, 'XtestSpell')
+  let buf = RunVimInTerminal('-S XtestSpell', {'rows': 8})
+  call VerifyScreenDump(buf, 'Test_spell_1', {})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('XtestSpell')
+endfunc
+
 let g:test_data_aff1 = [
       \"SET ISO8859-1",
       \"TRY esianrtolcdugmphbyfvkwjkqxz-\xEB\xE9\xE8\xEA\xEF\xEE\xE4\xE0\xE2\xF6\xFC\xFB'ESIANRTOLCDUGMPHBYFVKWJKQXZ",