1 files changed, 108 insertions, 0 deletions
diff --git a/src/nvim/testdir/test_fold.vim b/src/nvim/testdir/test_fold.vim
index 6da1b3d4a0..327f0f73f2 100644
--- a/src/nvim/testdir/test_fold.vim
+++ b/src/nvim/testdir/test_fold.vim
@@ -217,6 +217,26 @@ func Test_update_folds_expr_read()
   set foldmethod& foldexpr&
 endfunc
 
+" Test for what patch 8.1.0535 fixes.
+func Test_foldexpr_no_interrupt_addsub()
+  new
+  func! FoldFunc()
+    call setpos('.', getcurpos())
+    return '='
+  endfunc
+
+  set foldmethod=expr
+  set foldexpr=FoldFunc()
+  call setline(1, '1.2')
+
+  exe "norm! $\<C-A>"
+  call assert_equal('1.3', getline(1))
+
+  bwipe!
+  delfunc FoldFunc
+  set foldmethod& foldexpr&
+endfunc
+
 func Check_foldlevels(expected)
   call assert_equal(a:expected, map(range(1, line('$')), 'foldlevel(v:val)'))
 endfunc
@@ -881,4 +901,92 @@ func Test_fold_relative_move()
   set fdm& sw& wrap& tw&
 endfunc
 
+" Make sure a fold containing a nested fold is split correctly when using
+" foldmethod=indent
+func Test_fold_split()
+  new
+  let lines =<< trim END
+    line 1
+      line 2
+      line 3
+        line 4
+        line 5
+  END
+  call setline(1, lines)
+  setlocal sw=2
+  setlocal foldmethod=indent foldenable
+  call assert_equal([0, 1, 1, 2, 2], range(1, 5)->map('foldlevel(v:val)'))
+  call append(2, 'line 2.5')
+  call assert_equal([0, 1, 0, 1, 2, 2], range(1, 6)->map('foldlevel(v:val)'))
+  bw!
+endfunc
+
+" Make sure that when you append under a blank line that is under a fold with
+" the same indent level as your appended line, the fold expands across the
+" blank line
+func Test_indent_append_under_blank_line()
+  new
+  let lines =<< trim END
+    line 1
+      line 2
+      line 3
+  END
+  call setline(1, lines)
+  setlocal sw=2
+  setlocal foldmethod=indent foldenable
+  call assert_equal([0, 1, 1], range(1, 3)->map('foldlevel(v:val)'))
+  call append(3, '')
+  call append(4, '  line 5')
+  call assert_equal([0, 1, 1, 1, 1], range(1, 5)->map('foldlevel(v:val)'))
+  bw!
+endfunc
+
+" Make sure that when you delete 1 line of a fold whose length is 2 lines, the
+" fold can't be closed since its length (1) is now less than foldminlines.
+func Test_indent_one_line_fold_close()
+  let lines =<< trim END
+    line 1
+      line 2
+      line 3
+  END
+
+  new
+  setlocal sw=2 foldmethod=indent
+  call setline(1, lines)
+  " open all folds, delete line, then close all folds
+  normal zR
+  3delete
+  normal zM
+  call assert_equal(-1, foldclosed(2)) " the fold should not be closed
+
+  " Now do the same, but delete line 2 this time; this covers different code.
+  " (Combining this code with the above code doesn't expose both bugs.)
+  1,$delete
+  call setline(1, lines)
+  normal zR
+  2delete
+  normal zM
+  call assert_equal(-1, foldclosed(2))
+  bw!
+endfunc
+
+" Make sure that when appending [an indented line then a blank line] right
+" before a single indented line, the resulting extended fold can be closed
+func Test_indent_append_blank_small_fold_close()
+  new
+  setlocal sw=2 foldmethod=indent
+  " at first, the fold at the second line can't be closed since it's smaller
+  " than foldminlines
+  let lines =<< trim END
+    line 1
+      line 4
+  END
+  call setline(1, lines)
+  call append(1, ['  line 2', ''])
+  " close all folds
+  normal zM
+  call assert_notequal(-1, foldclosed(2)) " the fold should be closed now
+  bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab