Modify Length validator to match length exactly against a specified value

[hansondr]

• Renamed Length validator to LengthRange, parameters unchanged
• Created new Length validator, accepts integer to match length against

[ruimarinho]

Have you considered using { min: 10, max: 10 } to get the exact length match?

[hansondr]

I have, and that is what I was doing previously, but it just felt a little awkward. This could be chalked up to personal preference but this is the first library I've used where 'length' accepted anything other than an integer.

[ruimarinho]

Maybe Range could be taught how to deal with "length range" instead? Both options would require a major bump though.

[guillaumepotier]

Overall this is great.

Just wondering if creating a Length and a LengthRange validator is not overkilled, though a very good practice to separate concerns/interface. Wondering if could not only affect Range validator, detect that we have a string/int only (and not an array) and set both this.min and this.max to the unique value given.

README.md documentation should be updated too.

But overall I repeat this is a great contrib and PR, much appreciated :)

Best

[hansondr]

Folding LengthRange into Range sounds like a good course of action. I've updated the PR with this modification.

[ruimarinho]

IMO, Range({ min: x, max: y }) is more readable than Range(x, y), so I'd still support the first argument type.

[hansondr]

I can definitely see your point @ruimarinho, I went with the existing Range parameters to minimize breaking changes but would be easy to change should @guillaumepotier decide to go in this direction.

[guillaumepotier]

I'm a bit confused I have to say. I come from a PHP Symfony world where Length validator works with min and max, on strings, and Range the same way, on numbers.

I think Length could support { min: min, max: max } AND integer. A Length(integer) validator only do not have much use IMHO.

On the other side, Range validator have always been for numbers (I think users are used to that) and using it for strings to support Length with min and max feels unnatural.

What do you think?

[hansondr]

All good points @guillaumepotier, I may have been over zealous in my attempt to solve my particular use-case in Parsley. (A length validation where the min and max value is the same yields an awkward error message, This value length is invalid. It should be between 10 and 10 characters long.) I ended up solving this issue by creating my own validator which may be the best solution. The other obvious alternative being a special case length error message when both the min & max are equal but that means additional localization

[guillaumepotier]

You're right. I'll definitely think of a way to address this issue when I have time. Did you use #31 to add your validator? I'm interested by how you did properly it in fact :)

Best