SchemaParser.determineType does not determine input types as GraphQLInputObjectType #321

I am using directives from graphql-java-extended-validation.

A directive can apply to an input object types (GraphQLInputObjectType). A check makes sure that the current input instance is of type GraphQLInputObjectType before applying the directive.
As SchemaParser.determineType returns either a GraphQlList, a GraphQLNonNull or a GraphQLTypeReference, such a directive will never be applied.

I suppose there is reason for this behavior (I am new to graphql-java), but: could it be changed or could the instance check be performed in another way? I could allow the directive to run against GraphQLTypeReference as a workaround, but that's broader than my original scope (which iis only inputs, no GraphQLEnum, no GraphQLList, etc.).