Update validation message if rbenv_ruby is not set

[ivanovaleksey]

Hi,
I use new capistrano/rbenv feature that allows not to define rbenv_ruby in config file.
But the warning message wasn't updated and now it seems a little bit confusing to me.

If I intentionally removed rbenv_ruby from capistrano config "rbenv: rbenv_ruby is not set" looks like I still do something wrong.

It is already said in README

Alternatively, allow the remote host's rbenv to determine the appropriate Ruby version by omitting :rbenv_ruby. This approach is useful if you have a .ruby-version file in your project.

So I think it would be better to add this notice directly to the message.

P. S.
I am not sure about words in the message. Is remote hosts better than deployed hosts?

[capistrano-bot]

	1 Warning
⚠️	Please update CHANGELOG.md with a description of your changes. If this PR is not a user-facing change (e.g. just refactoring), you can disregard this.

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Here's an example of a CHANGELOG.md entry (place it immediately under the * Your contribution here! line):

* [#70](https://github.com/capistrano/rbenv/pull/70): Update validation message if rbenv_ruby is not set - [@ivanovaleksey](https://github.com/ivanovaleksey)

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[mattbrictson]

@ivanovaleksey Good point! Thanks for the PR.

@spikeheap Do you have an suggestion for if/how we should change the warning? It seems weird to warn the user when they are doing nothing wrong.

[ivanovaleksey]

I have updated the message a little bit:

• use info instead of warn
• use remote hosts instead of deployed hosts

Shoudn't it be ... defined by the remote hosts instead of ... defined on remote hosts?

[spikeheap]

Hi @ivanovaleksey, this PR looks good, particularly downgrading the message to info. @mattbrictson is spot on about warning users when they're doing the 'right' thing.

This does alter the initial behaviour, which required rbenv_ruby to be set, but IMHO this is more intuitive behaviour for the uses of rbenv I've seen.

👍

[ivanovaleksey]

@spikeheap thank you,
but should I use on or by? And should I use definite article?
Survey time 🎉

• rbenv: rbenv_ruby is not set; ruby version will be defined by the remote hosts via rbenv
• rbenv: rbenv_ruby is not set; ruby version will be defined on the remote hosts via rbenv

[spikeheap]

Hi @ivanovaleksey, I do love to bikeshed, so...

IMHO your 'by' option above reads slightly better than the others, and highlights that rbenv is picked up on each host. They all make sense though :).

[mattbrictson]

Looks good! Thanks for contribution ✨