Implement some CLI testing

[christophermaier]

To prevent regressions in basic CLI functionality, we should have an automated test suite that exercises it.

Possibilities:

• Cucumber + Aruba
• Bats

Informal polling of Habitat members (i.e., three of us talking in Slack one day) shows a roughly split opinion between those two options; other ideas are certainly up for discussion, as well.

As a way to decide, coding up an "easy" test and a "hard" test in each and comparing / contrasting the results would be informative.

UPDATE: As mentioned by @kbknapp below, assert_cli is a Rust library for CLI testing which may be worth investigating as well.

[christophermaier]

To broaden the field a bit, you can also use Aruba with RSpec, in case programming-via-regex (i.e., Cucumber) isn't your thing.

Also, we have institutional knowledge of testing Rust CLIs in delivery-cli.

[kbknapp]

There's also assert_cli which seems to be gaining popularity in the Rust community that may help. I haven't used the suggestions above, so I can't compare between them.

[christophermaier]

Thanks for the tip @kbknapp !

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We value your input and contribution. Please leave a comment if this issue still affects you.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We value your input and contribution. Please leave a comment if this issue still affects you.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We value your input and contribution. Please leave a comment if this issue still affects you.