Fix go-import meta data when enabled_git_access_protocol is a blank string

lib/gitlab/middleware/go.rb

@@ -42,12 +42,11 @@ module Gitlab
         project_url = URI.join(config.gitlab.url, path)
         import_prefix = strip_url(project_url.to_s)
 
-        repository_url = case current_application_settings.enabled_git_access_protocol
-                         when 'ssh'
+        repository_url = if current_application_settings.enabled_git_access_protocol == 'ssh'
                            shell = config.gitlab_shell
                            port = ":#{shell.ssh_port}" unless shell.ssh_port == 22
                            "ssh://#{shell.ssh_user}@#{shell.ssh_host}#{port}/#{path}.git"
-                         when 'http', nil
+                         else
                            "#{project_url}.git"
                          end
 

spec/lib/gitlab/middleware/go_spec.rb

@@ -127,6 +127,14 @@ describe Gitlab::Middleware::Go do
 
         include_examples 'go-get=1', enabled_protocol: nil
       end
+
+      context 'with nothing disabled (blank string)' do
+        before do
+          stub_application_setting(enabled_git_access_protocol: '')
+        end
+
+        include_examples 'go-get=1', enabled_protocol: nil
+      end
     end
 
     def go