When running astro plan --trace in a repository on the host filesystem the process hangs with:
[TRACE] 2019/05/23 01:48:51 terraform: copying tree from /host/home/Development/my-repo to /host/home/Development/my-repo/.astro/01DBH60VM64E5ZGFBF33H7GQJE/my-module/sandbox
It does work when run from /tmp.
Note that Windows doesn't support symbolic links and other UNIX features so it could be related (other applications using symbolic links have similar issues).