Dear all,
I'm using macOS 10.13.6, zsh 5.5.1 (x86_64-apple-darwin16.7.0) and grep (GNU grep) 3.1 packaged by Homebrew.
A weird behavior happened when completing `grep --no-*` arguments.
While typing `--no-group-separator`, which is a GNU only argument, after another `--no-*`, the cursor stoped in a wrong place and unable to finish completion. But it works right when `--no-group-separator` goes ahead.

Words might not be clear, so here's a demo video:
https://streamable.com/bxbdv

I would appreciate any ideas, thank you.

Best,
Joseph