fix when unicode is used for filename and dir

app/site_files.rb

@@ -130,7 +130,8 @@ post '/site_files/upload' do
       end
     end
 
-    file[:filename] = "#{dir_name}/#{site.scrubbed_path file[:filename]}"
+    file[:filename] = "#{dir_name.force_encoding('UTF-8')}/#{site.scrubbed_path file[:filename].force_encoding('UTF-8')}"
+
     if current_site.file_size_too_large? file[:tempfile].size
       file_upload_response "#{Rack::Utils.escape_html file[:filename]} is too large, upload cancelled."
     end

tests/api_tests.rb

@@ -423,6 +423,14 @@ describe 'api' do
       _(site_file_exists?('test.jpg')).must_equal true
     end
 
+    it 'works with unicode chars on filename and dir' do
+      create_site
+      basic_authorize @user, @pass
+      post '/api/upload', '詩經/詩經.jpg' => Rack::Test::UploadedFile.new('./tests/files/詩經.jpg', 'image/jpeg')
+      _(res[:result]).must_equal 'success'
+      _(site_file_exists?('詩經/詩經.jpg')).must_equal true
+    end
+
     it 'succeeds with two files' do
       create_site
       basic_authorize @user, @pass

tests/site_file_tests.rb

@@ -443,6 +443,14 @@ describe 'site_files' do
       end
     end
 
+    it 'works with unicode chars on filename and dir' do
+      upload(
+        'dir' => '詩經',
+        'files[]' => Rack::Test::UploadedFile.new('./tests/files/詩經.jpg', 'image/jpeg')
+      )
+      _(@site.site_files_dataset.where(path: '詩經/詩經.jpg').count).must_equal 1
+    end
+
     it 'does not register site changing until root index.html is changed' do
       upload(
         'dir' => 'derpie/derptest',