require "rails_helper" RSpec.describe BulkUpload::Downloader do subject(:downloader) { described_class.new(bulk_upload:) } let(:bulk_upload) { build(:bulk_upload) } let(:get_file_io) do io = StringIO.new io.write("hello") io.rewind io end # rubocop:disable RSpec/PredicateMatcher describe "#call" do let(:mock_storage_service) { instance_double(Storage::S3Service, get_file_io:) } it "downloads the file as a temporary file" do allow(Storage::S3Service).to receive(:new).and_return(mock_storage_service) downloader.call expect(mock_storage_service).to have_received(:get_file_io).with(bulk_upload.identifier) expect(File.exist?(downloader.path)).to be_truthy expect(File.read(downloader.path)).to eql("hello") end end # rubocop:enable RSpec/PredicateMatcher end