Merge branch 'revert_revert_issuable_lock' into 'master'

Revert the revert of Optimistic Locking

## What does this MR do?

It reverts the revert of optimistic lock https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5146 (and revert MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5245)

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/19871

Actually the code is already reviewed, except:
* Monkey patch `config/initializers/ar_monkey_patch.rb`
* We removed default values from migration `db/migrate/20160707104333_add_lock_to_issuables.rb`

See merge request !5623

2 files changed, 22 insertions, 0 deletions

diff --git a/spec/features/issues_spec.rb b/spec/features/issues_spec.rb
index 2e595959f04..d744d0eb6af 100644
--- a/spec/features/issues_spec.rb
+++ b/spec/features/issues_spec.rb
@@ -122,6 +122,17 @@ describe 'Issues', feature: true do
           expect(page).to have_content date.to_s(:medium)
         end
       end
+
+      it 'warns about version conflict' do
+        issue.update(title: "New title")
+
+        fill_in 'issue_title', with: 'bug 345'
+        fill_in 'issue_description', with: 'bug description'
+
+        click_button 'Save changes'
+
+        expect(page).to have_content 'Someone edited the issue the same time you did'
+      end
     end
   end
 
diff --git a/spec/features/merge_requests/edit_mr_spec.rb b/spec/features/merge_requests/edit_mr_spec.rb
index 4109e78f560..c77e719c5df 100644
--- a/spec/features/merge_requests/edit_mr_spec.rb
+++ b/spec/features/merge_requests/edit_mr_spec.rb
@@ -17,5 +17,16 @@ feature 'Edit Merge Request', feature: true do
     it 'has class js-quick-submit in form' do
       expect(page).to have_selector('.js-quick-submit')
     end
+
+    it 'warns about version conflict' do
+      merge_request.update(title: "New title")
+
+      fill_in 'merge_request_title', with: 'bug 345'
+      fill_in 'merge_request_description', with: 'bug description'
+
+      click_button 'Save changes'
+
+      expect(page).to have_content 'Someone edited the merge request the same time you did'
+    end
   end
 end