diff --git a/src/testdir/test_syntax.vim b/src/testdir/test_syntax.vim
index 024ba59..bbcd0d8 100644
--- a/src/testdir/test_syntax.vim
+++ b/src/testdir/test_syntax.vim
@@ -160,7 +160,7 @@
 
 func Test_syntax_completion()
   call feedkeys(":syn \<C-A>\<C-B>\"\<CR>", 'tx')
-  call assert_equal('"syn case clear cluster conceal enable include iskeyword keyword list manual match off on region reset spell sync', @:)
+  call assert_equal('"syn case clear cluster conceal enable foldlevel include iskeyword keyword list manual match off on region reset spell sync', @:)
 
   call feedkeys(":syn case \<C-A>\<C-B>\"\<CR>", 'tx')
   call assert_equal('"syn case ignore match', @:)
@@ -691,4 +691,87 @@
   call delete('Xddd.c')
 endfunc
 
+func Test_syntax_foldlevel()
+  new
+  call setline(1, [
+   \ 'void f(int a)',
+   \ '{',
+   \ '    if (a == 1) {',
+   \ '        a = 0;',
+   \ '    } else if (a == 2) {',
+   \ '        a = 1;',
+   \ '    } else {',
+   \ '        a = 2;',
+   \ '    }',
+   \ '    if (a > 0) {',
+   \ '        if (a == 1) {',
+   \ '            a = 0;',
+   \ '        } /* missing newline */ } /* end of outer if */ else {',
+   \ '        a = 1;',
+   \ '    }',
+   \ '    if (a == 1)',
+   \ '    {',
+   \ '        a = 0;',
+   \ '    }',
+   \ '    else if (a == 2)',
+   \ '    {',
+   \ '        a = 1;',
+   \ '    }',
+   \ '    else',
+   \ '    {',
+   \ '        a = 2;',
+   \ '    }',
+   \ '}',
+   \ ])
+  setfiletype c
+  syntax on
+  set foldmethod=syntax
+
+  call assert_fails('syn foldlevel start start', 'E390')
+  call assert_fails('syn foldlevel not_an_option', 'E390')
+
+  set foldlevel=1
+
+  syn foldlevel start
+  redir @c
+  syn foldlevel
+  redir END
+  call assert_equal("\nsyntax foldlevel start", @c)
+  syn sync fromstart
+  let a = map(range(3,9), 'foldclosed(v:val)')
+  call assert_equal([3,3,3,3,3,3,3], a) " attached cascade folds together
+  let a = map(range(10,15), 'foldclosed(v:val)')
+  call assert_equal([10,10,10,10,10,10], a) " over-attached 'else' hidden
+  let a = map(range(16,27), 'foldclosed(v:val)')
+  let unattached_results = [-1,17,17,17,-1,21,21,21,-1,25,25,25]
+  call assert_equal(unattached_results, a) " unattached cascade folds separately
+
+  syn foldlevel minimum
+  redir @c
+  syn foldlevel
+  redir END
+  call assert_equal("\nsyntax foldlevel minimum", @c)
+  syn sync fromstart
+  let a = map(range(3,9), 'foldclosed(v:val)')
+  call assert_equal([3,3,5,5,7,7,7], a) " attached cascade folds separately
+  let a = map(range(10,15), 'foldclosed(v:val)')
+  call assert_equal([10,10,10,13,13,13], a) " over-attached 'else' visible
+  let a = map(range(16,27), 'foldclosed(v:val)')
+  call assert_equal(unattached_results, a) " unattached cascade folds separately
+
+  set foldlevel=2
+
+  syn foldlevel start
+  syn sync fromstart
+  let a = map(range(11,14), 'foldclosed(v:val)')
+  call assert_equal([11,11,11,-1], a) " over-attached 'else' hidden
+
+  syn foldlevel minimum
+  syn sync fromstart
+  let a = map(range(11,14), 'foldclosed(v:val)')
+  call assert_equal([11,11,-1,-1], a) " over-attached 'else' visible
+
+  quit!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab