Project: QGIS
Version: 3.30
New is_feature_valid() and is_attribute_valid() functions are provided in QGIS expressions. Both functions validate a feature or attribute, based on the constraints attached to fields for a given vector layer. This enables users to leverage the select-by-expression utility to locate features that have unmet constraints. In addition, users can now use the rule-based renderer to provide visual feedback through symbology indicating the constraint validity state of rendered features.
This feature was developed by Mathieu Pellerin