Merge branch 'fix/mirror-update-error' into 'master'

Fix 500 error updating mirror URLs for projects

Updating the mirror URL with an empty URL should just render the mirror page with the flash message stating that the URL can't be blank. At the moment we throw an error 500 if the old URL had some import data.

Fixes https://gitlab.com/gitlab-org/gitlab-ee/issues/1082

See merge request !780

CHANGELOG-EE

 Please view this file on the master branch, on stable branches it's out of date.
 
 v 8.13.0 (unreleased)
+  - Fix 500 error updating mirror URLs for projects
 
 v 8.12.4 (unreleased)
   - [ES] Indexer works with smaller batches of repositories to not exceed NOFILE limit

app/models/project.rb

@@ -527,7 +527,7 @@ class Project < ActiveRecord::Base
   end
 
   def import_url
-    if import_data && super
+    if import_data && super.present?
       import_url = Gitlab::UrlSanitizer.new(super, credentials: import_data.credentials)
       import_url.full_url
     else

spec/requests/projects/mirrors_controller_spec.rb

+require 'spec_helper'
+
+describe Projects::MirrorsController do
+  let(:project) do
+    create(:project,
+           mirror: true,
+           mirror_user: user,
+           import_url: 'http://user:pass@test.url')
+  end
+  let(:user) { create(:user) }
+
+  describe 'updates the mirror URL' do
+    before do
+      project.team << [user, :master]
+      login_as(user)
+    end
+
+    it 'complains about passing an empty URL' do
+      patch namespace_project_mirror_path(project.namespace, project),
+        project: {
+        mirror: '1',
+        import_url: '',
+        mirror_user_id: '1',
+        mirror_trigger_builds: '0'
+      }
+
+      expect(response).to have_http_status :success
+      expect(response).to render_template(:show)
+      expect(response.body).to include('Import url can&#39;t be blank')
+    end
+  end
+end