TYPO3 Femanager Passwort additionalAttributes - typo3

Question

I want to extend the additionalAttributes with a second Attribute. In the original Partials it looks like this:
<f:form.password
id="femanager_field_password_repeat"
name="password_repeat"
class="input-block-level"
value=""
additionalAttributes="{femanager:Validation.FormValidationData(settings:settings,fieldName:'password_repeat')}" />
I try this:
additionalAttributes="{femanager:Validation.FormValidationData(settings:settings,fieldName:'password'),placeholder: '{password_repeat}'}" />
With several Verions of Escaping the femanager:Validation..... Got this Error:
The argument "additionalAttributes" was registered with type "array",
but is of type "string" in view helper
"TYPO3\CMS\Fluid\ViewHelpers\Form\PasswordViewHelper“
Any Ideas?

Answer 1

I think
Validation.FormValidationData()
is a viewhelper that returns a whole array which is expected for the attribute "additionalAttributes".
Because of that it's difficult to extend the array at this place.
But as far as I know the femanager-viewhelper itself offers the possibility to extend the final array, all to do is to give your array as a further argument which is called 'additionalAttributes' as well.
A short example:
<f:form.password
property="password"
additionalAttributes="{
femanager:Validation.FormValidationData(settings:settings,
fieldName:'password',
additionalAttributes:'{required:\'required\',pattern:\'.{8,}\'}')}"
}" />
Notice the array of 2 values (required and pattern).
I also recommend to have a look at the viewhelper on github:
https://github.com/TYPO3-extensions/femanager/blob/master/Classes/ViewHelpers/Validation/FormValidationDataViewHelper.php