1 files changed, 19 insertions, 0 deletions
diff --git a/src/nvim/testdir/test_undo.vim b/src/nvim/testdir/test_undo.vim
index adcdcb1cd9..4a5825a08f 100644
--- a/src/nvim/testdir/test_undo.vim
+++ b/src/nvim/testdir/test_undo.vim
@@ -364,6 +364,25 @@ func Test_wundo_errors()
   bwipe!
 endfunc
 
+" Check that reading a truncted undo file doesn't hang.
+func Test_undofile_truncated()
+  throw 'skipped: TODO: '
+  new
+  call setline(1, 'hello')
+  set ul=100
+  wundo Xundofile
+  let contents = readfile('Xundofile', 'B')
+
+  " try several sizes
+  for size in range(20, 500, 33)
+    call writefile(contents[0:size], 'Xundofile')
+    call assert_fails('rundo Xundofile', 'E825:')
+  endfor
+
+  bwipe!
+"  call delete('Xundofile')
+endfunc
+
 func Test_rundo_errors()
   call assert_fails('rundo XfileDoesNotExist', 'E822:')