Merge branch 'revert-lock-for-issuable' into 'master'

Revert "Optimistic locking for Issue and Merge Requests"

The migration to add `lock_version` in !5146 to every issue and merge request takes too long on GitLab.com since it has to add a default value of 0 to every row. Unfortunately, Rails 4.2 doesn't work properly if the value is left as `nil`; anything using optimistic locking cannot be edited. 

This bug was fixed in Rails 5.0 via this commit: https://github.com/rails/rails/commit/13772bfa49325a8dc26410d2dcb555665a320f92. I suggest we revert this change for now, and when we upgrade to Rails 5.0 we can reintroduce this feature.

See merge request !5245

app/controllers/projects/issues_controller.rb

@@ -119,10 +119,6 @@ class Projects::IssuesController < Projects::ApplicationController
         render json: @issue.to_json(include: { milestone: {}, assignee: { methods: :avatar_url }, labels: { methods: :text_color } })
       end
     end
-
-  rescue ActiveRecord::StaleObjectError
-    @conflict = true
-    render :edit
   end
   def referenced_merge_requests
@@ -220,7 +216,7 @@ class Projects::IssuesController < Projects::ApplicationController
   def issue_params
     params.require(:issue).permit(
       :title, :assignee_id, :position, :description, :confidential,
-      :milestone_id, :due_date, :state_event, :task_num, :lock_version, label_ids: []
+      :milestone_id, :due_date, :state_event, :task_num, label_ids: []
     )
   end

app/controllers/projects/merge_requests_controller.rb

@@ -196,9 +196,6 @@ class Projects::MergeRequestsController < Projects::ApplicationController
     else
       render "edit"
     end
-  rescue ActiveRecord::StaleObjectError
-    @conflict = true
-    render :edit
   end
   def remove_wip
@@ -427,7 +424,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
       :title, :assignee_id, :source_project_id, :source_branch,
       :target_project_id, :target_branch, :milestone_id,
       :state_event, :description, :task_num, :force_remove_source_branch,
-      :lock_version, label_ids: []
+      label_ids: []
     )
   end

app/models/concerns/issuable.rb

@@ -87,12 +87,6 @@ module Issuable
       User.find(assignee_id_was).update_cache_counts if assignee_id_was
       assignee.update_cache_counts if assignee
     end
-
-    # We want to use optimistic lock for cases when only title or description are involved
-    # http://api.rubyonrails.org/classes/ActiveRecord/Locking/Optimistic.html
-    def locking_enabled?
-      title_changed? || description_changed?
-    end
   end
   module ClassMethods

app/views/shared/issuable/_form.html.haml

 = form_errors(issuable)
-- if @conflict
-  .alert.alert-danger
-    Someone edited the #{issuable.class.model_name.human.downcase} the same time you did.
-    Please check out
-    = link_to "the #{issuable.class.model_name.human.downcase}", polymorphic_path([@project.namespace.becomes(Namespace), @project, issuable]), target: "_blank"
-    and make sure your changes will not unintentionally remove theirs
-
 .form-group
   = f.label :title, class: 'control-label'
   .col-sm-10
@@ -142,5 +135,3 @@
         = link_to 'Delete', polymorphic_path([@project.namespace.becomes(Namespace), @project, issuable]), data: { confirm: "#{issuable.class.name.titleize} will be removed! Are you sure?" },
                                                                                                   method: :delete, class: 'btn btn-danger btn-grouped'
       = link_to 'Cancel', polymorphic_path([@project.namespace.becomes(Namespace), @project, issuable]), class: 'btn btn-grouped btn-cancel'
-
-= f.hidden_field :lock_version

db/migrate/20160707104333_add_lock_to_issuables.rb

-# See http://doc.gitlab.com/ce/development/migration_style_guide.html
-# for more information on how to write migrations for GitLab.
-
-class AddLockToIssuables < ActiveRecord::Migration
-  include Gitlab::Database::MigrationHelpers
-  disable_ddl_transaction!
-
-  def up
-    add_column_with_default :issues, :lock_version, :integer, default: 0
-    add_column_with_default :merge_requests, :lock_version, :integer, default: 0
-  end
-
-  def down
-    remove_column :issues, :lock_version
-    remove_column :merge_requests, :lock_version
-  end
-end

db/schema.rb

@@ -70,11 +70,11 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.string   "recaptcha_site_key"
     t.string   "recaptcha_private_key"
     t.integer  "metrics_port",                          default: 8089
+    t.boolean  "akismet_enabled",                       default: false
+    t.string   "akismet_api_key"
     t.integer  "metrics_sample_interval",               default: 15
     t.boolean  "sentry_enabled",                        default: false
     t.string   "sentry_dsn"
-    t.boolean  "akismet_enabled",                       default: false
-    t.string   "akismet_api_key"
     t.boolean  "email_author_in_body",                  default: false
     t.integer  "default_group_visibility"
     t.boolean  "repository_checks_enabled",             default: false
@@ -84,10 +84,10 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.string   "health_check_access_token"
     t.boolean  "send_user_confirmation_email",          default: false
     t.integer  "container_registry_token_expire_delay", default: 5
+    t.boolean  "user_default_external",                 default: false,        null: false
     t.text     "after_sign_up_text"
     t.string   "repository_storage",                    default: "default"
     t.string   "enabled_git_access_protocol"
-    t.boolean  "user_default_external",                 default: false,       null: false
   end
   create_table "audit_events", force: :cascade do |t|
@@ -165,8 +165,8 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.text     "artifacts_metadata"
     t.integer  "erased_by_id"
     t.datetime "erased_at"
-    t.datetime "artifacts_expire_at"
     t.string   "environment"
+    t.datetime "artifacts_expire_at"
     t.integer  "artifacts_size"
   end
@@ -481,11 +481,10 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.string   "state"
     t.integer  "iid"
     t.integer  "updated_by_id"
-    t.integer  "moved_to_id"
     t.boolean  "confidential",  default: false
     t.datetime "deleted_at"
     t.date     "due_date"
-    t.integer  "lock_version",  default: 0,     null: false
+    t.integer  "moved_to_id"
   end
   add_index "issues", ["assignee_id"], name: "index_issues_on_assignee_id", using: :btree
@@ -625,7 +624,6 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.integer  "merge_user_id"
     t.string   "merge_commit_sha"
     t.datetime "deleted_at"
-    t.integer  "lock_version",              default: 0,     null: false
   end
   add_index "merge_requests", ["assignee_id"], name: "index_merge_requests_on_assignee_id", using: :btree
@@ -775,10 +773,10 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.integer  "user_id",                    null: false
     t.string   "token",                      null: false
     t.string   "name",                       null: false
-    t.boolean  "revoked",    default: false
-    t.datetime "expires_at"
     t.datetime "created_at",                 null: false
     t.datetime "updated_at",                 null: false
+    t.boolean  "revoked",    default: false
+    t.datetime "expires_at"
   end
   add_index "personal_access_tokens", ["token"], name: "index_personal_access_tokens_on_token", unique: true, using: :btree
@@ -898,9 +896,9 @@ ActiveRecord::Schema.define(version: 20160712171823) do
     t.string   "type"
     t.string   "title"
     t.integer  "project_id"
-    t.datetime "created_at",                               null: false
-    t.datetime "updated_at",                               null: false
-    t.boolean  "active",                                   null: false
+    t.datetime "created_at"
+    t.datetime "updated_at"
+    t.boolean  "active",                default: false,    null: false
     t.text     "properties"
     t.boolean  "template",              default: false
     t.boolean  "push_events",           default: true

features/project/merge_requests.feature

@@ -89,7 +89,7 @@ Feature: Project Merge Requests
     Then The list should be sorted by "Oldest updated"
   @javascript
-  Scenario: Visiting Merge Requests from a different Project after sorting
+  Scenario: Visiting Merge Requests from a differente Project after sorting
     Given I visit project "Shop" merge requests page
     And I sort the list by "Oldest updated"
     And I visit dashboard merge requests page

spec/features/issues_spec.rb

@@ -120,17 +120,6 @@ 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

spec/features/merge_requests/edit_mr_spec.rb

@@ -17,16 +17,5 @@ feature 'Edit Merge Request', feature: true do
     it 'form should have class js-quick-submit' 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