.custom() not working with promise

I am trying to get .custom() working from the check API but it appears that it’s not working?

Working (only showing essential information):

check.body('email').trim().isEmail().normalizeEmail().custom((_value) => {
    return true;
});

expressValidatorCheck.validationResult(req)..throw();

Not working (only showing essential information:

check.body('email').trim().isEmail().normalizeEmail().custom((_value) => {
    return Promise.resolve();
});

check.validationResult(req).throw();

The docs state: The custom validator may return a promise to indicate an async validation task. In case it’s rejected, the field is considered invalid. Therefore I would expect both examples to result in a “passed validation” however the second example always fails.

[gustavohenke]

Thanks for the report @jplusje.

The code currently expects all validators to unbox as a truthy value. This means even async validators that return promises should have a value, eg Promise.resolve(true) to be considered as passed.

[gustavohenke]

Yes, but as the docs say, a resolved promise should mean a passed validation, and this is not happening yet. Will fix it so this doesn’t happen to other users in the future.