Added Rack version specs to ensure the correct version is loaded.

spec/integration/rack_3_0/headers_spec.rb

@@ -1,77 +1,8 @@
 # frozen_string_literal: true
 
-describe Grape::Http::Headers, if: Gem::Version.new(Rack.release) >= Gem::Version.new('3') do
-  subject { last_response.headers }
-
-  describe 'returned headers should all be in lowercase' do
-    context 'when setting an header in an API' do
-      let(:app) do
-        Class.new(Grape::API) do
-          get do
-            header['GRAPE'] = '1'
-            return_no_content
-          end
-        end
-      end
-
-      before { get '/' }
-
-      it { is_expected.to include('grape' => '1') }
-    end
-
-    context 'when error!' do
-      let(:app) do
-        Class.new(Grape::API) do
-          rescue_from ArgumentError do
-            error!('error!', 500, { 'GRAPE' => '1' })
-          end
-
-          get { raise ArgumentError }
-        end
-      end
-
-      before { get '/' }
-
-      it { is_expected.to include('grape' => '1') }
-    end
-
-    context 'when redirect' do
-      let(:app) do
-        Class.new(Grape::API) do
-          get do
-            redirect 'https://www.ruby-grape.org/'
-          end
-        end
-      end
-
-      before { get '/' }
-
-      it { is_expected.to include('location' => 'https://www.ruby-grape.org/') }
-    end
-
-    context 'when options' do
-      let(:app) do
-        Class.new(Grape::API) do
-          get { return_no_content }
-        end
-      end
-
-      before { options '/' }
-
-      it { is_expected.to include('allow' => 'OPTIONS, GET, HEAD') }
-    end
-
-    context 'when cascade' do
-      let(:app) do
-        Class.new(Grape::API) do
-          version 'v0', using: :path, cascade: true
-          get { return_no_content }
-        end
-      end
-
-      before { get '/v1' }
-
-      it { is_expected.to include('x-cascade' => 'pass') }
-    end
-  end
+describe Grape::Http::Headers do
+  it { expect(described_class::ALLOW).to eq('allow') }
+  it { expect(described_class::LOCATION).to eq('location') }
+  it { expect(described_class::TRANSFER_ENCODING).to eq('transfer-encoding') }
+  it { expect(described_class::X_CASCADE).to eq('x-cascade') }
 end

spec/integration/rack_3_0/version_spec.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+describe Rack do
+  it { expect(Gem::Version.new(described_class.release).segments.first).to eq 3 }
+end