Render 'invalid' if #target_branch_missing?

app/controllers/projects/merge_requests_controller.rb

@@ -28,15 +28,14 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
   end
 
   def show
-    validates_merge_request
-
-    # Return if the response has already been rendered
-    return if response_body
     close_merge_request_if_no_source_project
     mark_merge_request_mergeable
 
     respond_to do |format|
       format.html do
+        # use next to appease Rubocop
+        next render('invalid') if target_branch_missing?
+
         # Build a note object for comment form
         @note = @project.notes.new(noteable: @merge_request)
 
@@ -234,20 +233,6 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
   alias_method :issuable, :merge_request
   alias_method :awardable, :merge_request
 
-  def validates_merge_request
-    # Show git not found page
-    # if there is no saved commits between source & target branch
-    if @merge_request.has_no_commits?
-      # and if target branch doesn't exist
-      return invalid_mr unless @merge_request.target_branch_exists?
-    end
-  end
-
-  def invalid_mr
-    # Render special view for MR with removed target branch
-    render 'invalid'
-  end
-
   def merge_params
     params.permit(merge_params_attributes)
   end
@@ -269,6 +254,10 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
 
   private
 
+  def target_branch_missing?
+    @merge_request.has_no_commits? && !@merge_request.target_branch_exists?
+  end
+
   def mark_merge_request_mergeable
     @merge_request.check_if_can_be_merged
   end