1 files changed, 29 insertions, 0 deletions
diff --git a/spec/models/note_diff_file_spec.rb b/spec/models/note_diff_file_spec.rb
index 591c1a89748..b15bedd257e 100644
--- a/spec/models/note_diff_file_spec.rb
+++ b/spec/models/note_diff_file_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 describe NoteDiffFile do
@@ -8,4 +10,31 @@ describe NoteDiffFile do
   describe 'validations' do
     it { is_expected.to validate_presence_of(:diff_note) }
   end
+
+  describe '.referencing_sha' do
+    let!(:diff_note) { create(:diff_note_on_commit) }
+
+    let(:note_diff_file) { diff_note.note_diff_file }
+    let(:project) { diff_note.project }
+
+    it 'finds note diff files by project and sha' do
+      found = described_class.referencing_sha(diff_note.commit_id, project_id: project.id)
+
+      expect(found).to contain_exactly(note_diff_file)
+    end
+
+    it 'excludes note diff files with the wrong project' do
+      other_project = create(:project)
+
+      found = described_class.referencing_sha(diff_note.commit_id, project_id: other_project.id)
+
+      expect(found).to be_empty
+    end
+
+    it 'excludes note diff files with the wrong sha' do
+      found = described_class.referencing_sha(Gitlab::Git::BLANK_SHA, project_id: project.id)
+
+      expect(found).to be_empty
+    end
+  end
 end