1 files changed, 9 insertions, 7 deletions
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index dd65a9a8b86..b8f36a2c958 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -11,6 +11,9 @@ class MergeRequestDiff < ActiveRecord::Base
 
   belongs_to :merge_request
 
+  serialize :st_commits
+  serialize :st_diffs
+
   state_machine :state, initial: :empty do
     state :collected
     state :overflow
@@ -22,8 +25,7 @@ class MergeRequestDiff < ActiveRecord::Base
     state :overflow_diff_lines_limit
   end
 
-  serialize :st_commits
-  serialize :st_diffs
+  scope :viewable, -> { without_state(:empty) }
 
   # All diff information is collected from repository after object is created.
   # It allows you to override variables like head_commit_sha before getting diff.
@@ -125,11 +127,7 @@ class MergeRequestDiff < ActiveRecord::Base
   end
 
   def commits_sha
-    if @commits
-      commits.map(&:sha)
-    else
-      st_commits.map { |commit| commit[:id] }
-    end
+    st_commits.map { |commit| commit[:id] }
   end
 
   def diff_refs
@@ -174,6 +172,10 @@ class MergeRequestDiff < ActiveRecord::Base
     CompareService.new.execute(project, head_commit_sha, project, sha, straight: straight)
   end
 
+  def commits_count
+    st_commits.count
+  end
+
   private
 
   # Old GitLab implementations may have generated diffs as ["--broken-diff"].