Automatically detect ubrn.config.yaml

[kraenhansen]

I don't expect developers to have more than one config per package. While I understand it's expected for developers to add calls of the CLI to their package.json "scripts", it would be neat if the CLI found the configuration automagically, instead of having to pass it on every invocation.

[jhugman]

This is a great idea. Do you think it should be as simple as adding a default value to the --config option? or something more complicated?

[kraenhansen]

default value to the --config option

• If both the ./ubrn.config.yaml file and --config paramater is missing: I'd expect an error message asking me to provide either the file or the path of a config file elsewhere.
• If I'm explicitly providing a --config however: I'd expect that to error with a clear message telling me the path of the missing file (so I can understand where it's looking at).