I have a content type using a multivalued taxonomy-term field using entity reference.
My user prefers to add new terms to the taxonomy directly from the node creation window.
Inline entity form is almost doing everything we need except one thing: we dont want duplicate values for the taxonomy terms.
For example: if there is the taxonomy term "fruit" we dont want it to be duplicated and it must keep only one term named "fruit" at all.
I can make the taxonomy core interface respect this kind of validation using the module "field_validation" (https://drupal.org/project/field_validation) and it's submodule "property validation".
But when I create a new term using inline entity form the rule is not being checked.
Is there a way to integrate both modules or another possible approach to achieve what I need?