in src/main/java/org/apache/sling/provisioning/model/ModelUtility.java [359:370]
public static Map<Traceable, String> validateIncludingVersion(final Model model) {
Map<Traceable, String> errors = validate(model);
for(final Feature feature : model.getFeatures()) {
if ( feature.getVersion() == null ) {
if ( errors == null ) {
errors = new HashMap<>();
}
addError(errors, feature, "Feature must have a version.");
}
}
return errors;
}