vim-patch:8.2.3121: 'listchars' "exceeds" character appears in foldcolumn

Problem:    'listchars' "exceeds" character appears in foldcolumn. Window
            separator is missing. (Leonid V.  Fedorenchik)
Solution:   Only draw the "exceeds" character in the text area.  Break the
            loop when not drawing the text. (closes vim/vim#8524)
https://github.com/vim/vim/commit/41fb723ee97baa2f095cde601a5a144b168b7a6b

3 files changed, 114 insertions, 3 deletions

diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index 538604cf79..ab726dfdb0 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -4232,6 +4232,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool noc
     // Show "extends" character from 'listchars' if beyond the line end and
     // 'list' is set.
     if (wp->w_p_lcs_chars.ext != NUL
+        && draw_state == WL_LINE
         && wp->w_p_list
         && !wp->w_p_wrap
         && filler_todo <= 0
@@ -4427,7 +4428,8 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool noc
      */
     if ((wp->w_p_rl ? (col < 0) : (col >= grid->Columns))
         && foldinfo.fi_lines == 0
-        && (*ptr != NUL
+        && (draw_state != WL_LINE
+            || *ptr != NUL
             || filler_todo > 0
             || (wp->w_p_list && wp->w_p_lcs_chars.eol != NUL
                 && p_extra != at_end_str)
diff --git a/src/nvim/testdir/test_listchars.vim b/src/nvim/testdir/test_listchars.vim
index 0bcbd9c4a5..c6e2ebd406 100644
--- a/src/nvim/testdir/test_listchars.vim
+++ b/src/nvim/testdir/test_listchars.vim
@@ -1,6 +1,8 @@
 " Tests for 'listchars' display with 'list' and :list
 
+source check.vim
 source view_util.vim
+source screendump.vim
 
 func Test_listchars()
   enew!
@@ -517,4 +519,34 @@ func Test_listchars_window_local()
   set list& listchars&
 endfunc
 
+func Test_listchars_foldcolumn()
+  CheckScreendump
+
+  let lines =<< trim END
+      call setline(1, ['aaa', '', 'a', 'aaaaaa'])
+      vsplit
+      vsplit
+      windo set signcolumn=yes foldcolumn=1 winminwidth=0 nowrap list listchars=extends:>,precedes:<
+  END
+  call writefile(lines, 'XTest_listchars')
+
+  let buf = RunVimInTerminal('-S XTest_listchars', {'rows': 10, 'cols': 60})
+
+  call term_sendkeys(buf, "13\<C-W>>")
+  call VerifyScreenDump(buf, 'Test_listchars_01', {})
+  call term_sendkeys(buf, "\<C-W>>")
+  call VerifyScreenDump(buf, 'Test_listchars_02', {})
+  call term_sendkeys(buf, "\<C-W>>")
+  call VerifyScreenDump(buf, 'Test_listchars_03', {})
+  call term_sendkeys(buf, "\<C-W>>")
+  call VerifyScreenDump(buf, 'Test_listchars_04', {})
+  call term_sendkeys(buf, "\<C-W>>")
+  call VerifyScreenDump(buf, 'Test_listchars_05', {})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('XTest_listchars')
+endfunc
+
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/test/functional/legacy/listchars_spec.lua b/test/functional/legacy/listchars_spec.lua
index dc6ccd3628..7a1afa1fd6 100644
--- a/test/functional/legacy/listchars_spec.lua
+++ b/test/functional/legacy/listchars_spec.lua
@@ -1,7 +1,8 @@
 -- Tests for 'listchars' display with 'list' and :list.
 
 local helpers = require('test.functional.helpers')(after_each)
-local feed, insert, source = helpers.feed, helpers.insert, helpers.source
+local Screen = require('test.functional.ui.screen')
+local feed, insert, exec = helpers.feed, helpers.insert, helpers.exec
 local clear, feed_command, expect = helpers.clear, helpers.feed_command, helpers.expect
 
 -- luacheck: ignore 621 (Indentation)
@@ -13,7 +14,7 @@ describe("'listchars'", function()
 
   -- luacheck: ignore 613 (Trailing whitespace in a string)
   it("works with 'list'", function()
-    source([[
+    exec([[
       function GetScreenCharsForLine(lnum)
         return join(map(range(1, virtcol('$')), 'nr2char(screenchar(a:lnum, v:val))'), '')
       endfunction
@@ -98,4 +99,80 @@ describe("'listchars'", function()
       .....h>-$
       iii<<<<><<$]])
   end)
+
+  it('"exceeds" character does not appear in foldcolumn vim-patch:8.2.3121', function()
+    local screen = Screen.new(60, 10)
+    screen:attach()
+    exec([[
+      call setline(1, ['aaa', '', 'a', 'aaaaaa'])
+      vsplit
+      vsplit
+      windo set signcolumn=yes foldcolumn=1 winminwidth=0 nowrap list listchars=extends:>,precedes:<
+    ]])
+    feed('13<C-W>>')
+    screen:expect([[
+         aaa              │   a>│   ^aaa                           |
+                          │     │                                 |
+         a                │   a │   a                             |
+         aaaaaa           │   a>│   aaaaaa                        |
+      ~                   │~    │~                                |
+      ~                   │~    │~                                |
+      ~                   │~    │~                                |
+      ~                   │~    │~                                |
+      [No Name] [+]        <[+]  [No Name] [+]                    |
+                                                                  |
+    ]])
+    feed('<C-W>>')
+    screen:expect([[
+         aaa              │   >│   ^aaa                            |
+                          │    │                                  |
+         a                │   a│   a                              |
+         aaaaaa           │   >│   aaaaaa                         |
+      ~                   │~   │~                                 |
+      ~                   │~   │~                                 |
+      ~                   │~   │~                                 |
+      ~                   │~   │~                                 |
+      [No Name] [+]        <+]  [No Name] [+]                     |
+                                                                  |
+    ]])
+    feed('<C-W>>')
+    screen:expect([[
+         aaa              │   │   ^aaa                             |
+                          │   │                                   |
+         a                │   │   a                               |
+         aaaaaa           │   │   aaaaaa                          |
+      ~                   │~  │~                                  |
+      ~                   │~  │~                                  |
+      ~                   │~  │~                                  |
+      ~                   │~  │~                                  |
+      [No Name] [+]        <]  [No Name] [+]                      |
+                                                                  |
+    ]])
+    feed('<C-W>>')
+    screen:expect([[
+         aaa              │  │   ^aaa                              |
+                          │  │                                    |
+         a                │  │   a                                |
+         aaaaaa           │  │   aaaaaa                           |
+      ~                   │~ │~                                   |
+      ~                   │~ │~                                   |
+      ~                   │~ │~                                   |
+      ~                   │~ │~                                   |
+      [No Name] [+]        <  [No Name] [+]                       |
+                                                                  |
+    ]])
+    feed('<C-W>>')
+    screen:expect([[
+         aaa              │ │   ^aaa                               |
+                          │ │                                     |
+         a                │ │   a                                 |
+         aaaaaa           │ │   aaaaaa                            |
+      ~                   │~│~                                    |
+      ~                   │~│~                                    |
+      ~                   │~│~                                    |
+      ~                   │~│~                                    |
+      [No Name] [+]        < [No Name] [+]                        |
+                                                                  |
+    ]])
+  end)
 end)