Fix specs and test on rack ~> 1.0 and rack ~> 2.0.0.

Author: ioquatix

.travis.yml

@@ -13,6 +13,10 @@ matrix:
         - bundle exec danger
     - rvm: 2.7.0
       gemfile: Gemfile
+    - rvm: 2.7.0
+      gemfile: gemfiles/rack1.gemfile
+    - rvm: 2.7.0
+      gemfile: gemfiles/rack2-0.gemfile
     - rvm: 2.7.0
       gemfile: gemfiles/rack_edge.gemfile
     - rvm: 2.7.0

gemfiles/rack1.gemfile

@@ -0,0 +1,4 @@
+
+eval_gemfile("../Gemfile")
+
+gem 'rack', '~> 1.0'

gemfiles/rack2-0.gemfile

@@ -0,0 +1,4 @@
+
+eval_gemfile("../Gemfile")
+
+gem 'rack', '~> 1.0'

spec/grape/middleware/formatter_spec.rb

@@ -379,12 +379,16 @@ def to_xml
   end
 
   context 'send file' do
-    let(:body) { Grape::ServeFile::FileResponse.new('file') }
-    let(:app) { ->(_env) { [200, {}, body] } }
+    let(:file) {double(File)}
+    let(:file_body) { Grape::ServeFile::FileResponse.new(file) }
+    let(:app) { ->(_env) { [200, {}, file_body] } }
 
-    it 'returns Grape::Uril::SendFileReponse' do
+    it 'returns a file response' do
       env = { 'PATH_INFO' => '/somewhere', 'HTTP_ACCEPT' => 'application/json' }
-      expect(subject.call(env)).to be_a(Array)
+      status, headers, body = subject.call(env)
+      expect(status).to be == 200
+      expect(headers).to be == {"Content-Type"=>"application/json"}
+      expect(body).to be file
     end
   end