Centralize some string definitions in the linting rules

[ee7]

I don't think this PR is a strict improvement, but I think overall it makes the spec more readable. The reader of

non-empty, non-blank string
non-empty, non-blank, lowercased string using kebab-case

will no longer ask questions like:

• "do we allow a whitespace-only string somewhere?"
• "is there a kebab-case string somewhere that's allowed to contain uppercase?"

I don't love the phrase "non-trivial string". Can we think of something better?

[iHiD]

Thanks for this.

Could we use non-blank? As we define it, I think that's fine. (and also the definition you use is what Rails uses for non-blank too, so that fits with the consumer)

[iHiD]

Looks good to me! I'll get Erik to confirm he's happy before merging :)

[ee7]

@iHiD Can we merge this? I'll base another couple of PRs on top of these changes.

[iHiD]

Certainly.