File type param uses wrong name in both docs UI and when sending test request from docs.

Grape swagger is working brilliantly for all my endpoints apart from this one that requires a File param. The grape api endpoint works fine and all params validate when I call the api from my own code but the auto generated swagger docs are not working right with this one param. Here's the param validation code:

params :requires_pdf_data do
    requires :data, type: Rack::Multipart::UploadedFile, desc: 'Mulitpart file upload accepts application/pdf'
end

And here's a screenshot of how swagger shows that param:

When I call the endpoint from my own code it works perfectly but from swagger it always says that the data param is missing. Is this a bug or am I missing something? Any ideas?

Start by reproducing the requires_pdf_data endpoint in the generated Swagger docs with its data multipart file parameter, then compare the parameter name shown in the docs UI with the name sent in the test request. Done means the docs UI and generated request send the correct name and the endpoint no longer reports the file parameter as missing.