commit https://github.com/vim/vim/commit/e25bc5abb4621c6263b0248988a207d53b57fc54 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jul 21 21:23:38 2016 +0200 patch 7.4.2087 Problem: Digraph code test coverage is still low. Solution: Add more tests. (Christian Brabandt)

start:
test for empty string: ok
test for 1 char: ok
test for 3 chars: ok
test for contains meta char: ok
test for contains non-ascii char: ok