shards check should exit zero if no shards.lock exists and no dependencies are required

[bacongobbler]

Hey everyone! Just playing around with Crystal a bit and I'm starting to write a Heroku buildpack for Crystal. Just starting to get my feet wet with shards. Cool project!

Given a sample application such as https://github.com/fishworks/example-crystal with no external dependencies (just the standard library), I would expect that shards check would consider it a valid application given that shards install will not produce a shard.lock file. Is shards check the proper way to "lint" a project for correctness?

This was tested with crystal 0.20.1, installed via homebrew.

[ysbaddaden]

Indeed. Thanks for reporting!