Spec for ruby-grape#786.

spec/grape/integration/utf8_encoding_spec.rb

@@ -0,0 +1,52 @@
+# -*- encoding : utf-8 -*-
+# https://github.com/intridea/grape/issues/786
+
+require 'spec_helper'
+require 'shared/versioning_examples'
+
+describe Grape::API do
+  module EncodingSpec
+    class API < Grape::API
+      params do
+        requires :a
+        requires :b
+        optional :file, type: Rack::Multipart::UploadedFile
+      end
+      post do
+        [
+          params[:a].encoding,
+          params[:b].encoding,
+          parmas[:file] ? params[:file].encoding : nil
+        ].compact.map(&:to_s).join(",")
+      end
+    end
+  end
+
+  subject { EncodingSpec::API.new }
+
+  def app
+    subject
+  end
+
+  describe 'encoding' do
+    it 'uses UTF-8 encoding for UTF-8 strings' do
+      post '/', a: "aaa", b: "😈"
+
+      expect(last_response.body).to eq("UTF-8,UTF-8")
+    end
+
+    it 'uses UTF-8 encoding for UTF-8 strings also when sending a file' do
+      header 'Content-Type', 'multipart/form-data'
+      post '/', a: "aaa", b: "😈", file: Rack::Test::UploadedFile.new("grape.png", 'image/png', true)
+
+      expect(last_response.body).to eq("UTF-8,UTF-8")
+    end
+
+    it 'uses UTF-8 encoding for UTF-8 strings also when sending a file and charset=UTF-8 content type' do
+      header 'Content-Type', 'multipart/form-data; charset=UTF-8'
+      post '/', a: "aaa", b: "😈", file: Rack::Test::UploadedFile.new("grape.png", 'image/png', true)
+
+      expect(last_response.body).to eq("UTF-8,UTF-8")
+    end
+  end
+end