diff --git a/src/testdir/test_writefile.vim b/src/testdir/test_writefile.vim
index c858b75..f42ec14 100644
--- a/src/testdir/test_writefile.vim
+++ b/src/testdir/test_writefile.vim
@@ -676,4 +676,22 @@
   %bw!
 endfunc
 
+func Test_read_write_bin()
+  " write file missing EOL
+  call writefile(['noeol'], "XNoEolSetEol", 'bS')
+  call assert_equal(0z6E6F656F6C, readfile('XNoEolSetEol', 'B'))
+
+  " when file is read 'eol' is off
+  set ff=unix nofixeol
+  e XNoEolSetEol
+  call assert_equal(0, &eol)
+
+  " writing with 'eol' set adds the newline
+  setlocal eol
+  w
+  call assert_equal(0z6E6F656F6C0A, readfile('XNoEolSetEol', 'B'))
+
+  call delete('XNoEolSetEol')
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab