Merge Button v1 complete

app/controllers/merge_requests_controller.rb

@@ -102,6 +102,7 @@ class MergeRequestsController < ApplicationController
 
   def automerge
     render_404 unless @merge_request.open? && @merge_request.can_be_merged?
+    return access_denied! unless can?(current_user, :accept_mr, @project)
     @merge_request.automerge!(current_user)
   end
 

app/models/ability.rb

@@ -46,6 +46,7 @@ class Ability
       :admin_team_member,
       :admin_merge_request,
       :admin_note,
+      :accept_mr,
       :admin_wiki
     ] if project.master_access_for?(user) || project.owner == user
 

app/models/merge_request.rb

@@ -73,7 +73,7 @@ class MergeRequest < ActiveRecord::Base
   end
 
   def check_if_can_be_merged
-    self.state = if GitlabMerge.new(self).can_be_merged?
+    self.state = if GitlabMerge.new(self, self.author).can_be_merged?
                    CAN_BE_MERGED
                  else
                    CANNOT_BE_MERGED
@@ -175,7 +175,7 @@ class MergeRequest < ActiveRecord::Base
   end
 
   def automerge!(current_user)
-    if GitlabMerge.new(self).merge
+    if GitlabMerge.new(self, current_user).merge
       self.merge!(current_user.id)
       true
     end

app/views/merge_requests/show.html.haml

@@ -52,7 +52,8 @@
           Closed by #{@merge_request.closed_event.author_name} 
           %small #{time_ago_in_words(@merge_request.closed_event.created_at)} ago.
 
-- if @merge_request.open? && @commits.any?
+
+- if @merge_request.open? && @commits.any? && can?(current_user, :accept_mr, @project)
   - if @merge_request.can_be_merged?
     .ui-box.padded
       %p