Updating a validatedObservable will not reset initial validation result

[thomaux]

I've encountered a problem regarding the validatedObservable.

When first set, validation occurs correctly, however after being set to a new observable, the validation result stays the same.

You can use this fiddle to reproduce the issue: http://jsfiddle.net/anzeo/56nLM/

Steps:

1. Fill in a value and click 'add contact'
2. Click 'update contact'
3. Click 'add contact' it will alert true although no value is specified

(note: the scenario could be inversed by directly clicking on 'update contact' and then filling in a value and clicking 'add contact'

[mcottingham]

Is there a known workaround for this issue?

[DenEddie]

Hi,

I think this project is a bit lost in what is really important. But whatever, I fixed this issue, but I'm not a contributor.

In the knockout.validation.js file just change:

ko.validatedObservable = function (initialValue) {
    if (!ko.validation.utils.isObject(initialValue)) { return ko.observable(initialValue).extend({ validatable: true }); }

    var obsv = ko.observable(initialValue);
    obsv.errors = ko.validation.group(initialValue);
    obsv.isValid = ko.computed(function () {
        return obsv.errors().length === 0;
    });

    return obsv;
};

into:

ko.validatedObservable = function (initialValue) {
    if (!ko.validation.utils.isObject(initialValue)) { return ko.observable(initialValue).extend({ validatable: true }); }

    var obsv = ko.observable();

    obsv.subscribe(function(newValue){
        obsv.errors = ko.validation.group(newValue);
        obsv.isValid = ko.computed(function () {
            return obsv.errors().length === 0;
        });
    });

    obsv(initialValue);
    return obsv;
};

Hopefully it will be added in the newest release.

[stevegreatrex]

Hi @DenEddie, thanks for the contribution. There's no need to be a "contributor" though - you can fork the repo, make the change in your local branch and then raise a pull request.

Ideally we would want some unit tests as well though

[DenEddie]

Hi @stevegreatrex, I would love to contribute this partials code, but the problem is I didn't figure out how the current structure in code is done. I still use the 1 file library, but I see that they are being split up in multiple files. Let me know where you most like to see this and what sort of unit test you like and I contribute this :)

[stalniy]

Don't think that it's a good idea to hold a whole object inside observable. A better way is to create one view model inside another and then only updates its values using something like ko.viewmodel plugin or manually and reset modification state

[crissdev]

obsv.subscribe(function(newValue) {
    obsv.errors = ko.validation.group(newValue);
    ...
});

This will not work because it overwrites the errors property causing all previous subscribers to not receive further notifications.