Problems with .isValid() on required checkboxes

[krnlde]

Hey guys! I experienced some problems when making checkboxes required (for example terms and conditions).

See here for reference: http://jsfiddle.net/v6d5y3or/

Expected behaviour: Form .isValid() should reflect the checkbox value: checkbox.true = form.true and checkbox.false = form.false

Actual behaviour: Form .isValid() is always true: checkbox.true = form.true and checkbox.false = form.true

I'm not really sure why this happens and one would think that required: true works together with the checked binding.

A temporary solution to me is to implement a custom validator to make it work as expected:

ko.observable(false).extend({
  validation: [{
    validator: (value, params) => Boolean(value)
  }]
})

[krnlde]

Can I consider this project dead when, after 2 weeks, nobody answers or even just labels this issue?

[ichepurnoy]

my best guess is, you have misused ko.validatedObservable.
Namely, you did not extend it. Please see this example.
http://jsfiddle.net/ichepurnoy/evxca44L/
I'm no pro, just trying to figure things out, and it's a pity that the docs not contain many things like this, that are already in the library.
If i'm right, pls , try to use correct syntax for validatedObservable. Maybe get it from library itself.
The project's not dead, and if it even was, we are pretty much stuck with it, as I see no replacement for it currently )

[ichepurnoy]

I now realised that you have used validatedObservable like in 'Getting Started' .. But check inside the library, maybe docs mislead you on this.
Another thing, check http://jsfiddle.net/ichepurnoy/7brjnewm/, I replaced your input with input type = text.
It works (!), although I also had to change the way the viewmodel is instantiated.
It may be something in knockout itself (not ko.validation plugin), or the way its 'checked' binding works.

[krnlde]

I extended the VM correctly in the jsfiddle above. Also I know it works on a text input - but not on a checkbox/radio. That's why I started this issue.

[crissdev]

@krnlde The required rule converts the input value to a string and checks its length. For a boolean value the resulting string will always have a length greater than 0, thus making the validation to always pass. (https://github.com/Knockout-Contrib/Knockout-Validation/blob/2.0.3/src/rules.js#L45)
A simple fix would be to check for false to skip the conversion to string (that is a change to https://github.com/Knockout-Contrib/Knockout-Validation/blob/2.0.3/src/rules.js#L27).
Do you want to make a PR to fix this?

[krnlde]

But L27 is a shortcut and will return with false if required === true. I'd rather prefer to do another type check as in L32:

if (typeof (val) === 'boolean'`) return val;

What do you think @crissdev

[crissdev]

@krnlde Adding false to the existing checks will fail validation if the field is required - which is the desired behaviour. http://jsfiddle.net/v6d5y3or/2/

[krnlde]

Alright thanks, I'll do a PR. Should I also build the dist?

[krnlde]

Any news here?

[crissdev]

Please check your PR. It seems the tests are falling.

[krnlde]

Not anymore.

[crissdev]

Looks good. Thanks.