1 files changed, 17 insertions, 1 deletions
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 70005a87f4b..cd5b345bae5 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -91,6 +91,10 @@ class MergeRequest < ActiveRecord::Base
     around_transition do |merge_request, transition, block|
       Gitlab::Timeless.timeless(merge_request, &block)
     end
+
+    after_transition unchecked: :cannot_be_merged do |merge_request, transition|
+      TodoService.new.merge_request_became_unmergeable(merge_request)
+    end
   end
 
   validates :source_project, presence: true, unless: [:allow_broken, :importing?, :closed_without_fork?]
@@ -898,10 +902,22 @@ class MergeRequest < ActiveRecord::Base
   end
 
   def has_commits?
-    commits_count > 0
+    merge_request_diff && commits_count > 0
   end
 
   def has_no_commits?
     !has_commits?
   end
+
+  def mergeable_with_slash_command?(current_user, autocomplete_precheck: false, last_diff_sha: nil)
+    return false unless can_be_merged_by?(current_user)
+
+    return true if autocomplete_precheck
+
+    return false unless mergeable?(skip_ci_check: true)
+    return false if head_pipeline && !(head_pipeline.success? || head_pipeline.active?)
+    return false if last_diff_sha != diff_head_sha
+
+    true
+  end
 end