Expected Behaviour

I need to include/exclude data for relationships depending on external parameter given to serializer.

For example BundleSerializer.new(bundle, params: { lazy_load_instruments_data: true }) should exclude the data for relationships.

And BundleSerializer.new(bundle, params: { lazy_load_instruments_data: false }) should include the data

It could be resolved by passing the proc as an argument to lazy_load_data

    has_many :instruments, lazy_load_data: Proc.new { |_, params| params[:lazy_load_instruments_data] == true }, links: {
        related: -> (object) {
          url_helpers.instruments_url(related_id: object.id)
        }
    }

Actual Behaviour

Even if we pass a proc as in example above it always count the lazy_load_data as true because:

output_hash[key][:data] = ids_hash_from_record_and_relationship(record, serialization_params) || empty_case unless lazy_load_data && !included

https://github.com/jsonapi-serializer/jsonapi-serializer/blob/master/lib/fast_jsonapi/relationship.rb#L48

Steps to Reproduce the Problem

1. Pass conditional Proc as value of lazy_load_data
2. It always count lazy_load_data: true even if Proc returns false

Specifications

• Version: 2.1.0
• Ruby version: 2.7.1p83

It's not a bug but the feature request, I can add it just want to check if we are ok with this behaviour