1 files changed, 29 insertions, 0 deletions
diff --git a/spec/lib/gitlab/background_migration/backfill_note_discussion_id_spec.rb b/spec/lib/gitlab/background_migration/backfill_note_discussion_id_spec.rb
new file mode 100644
index 00000000000..dcb4ede36af
--- /dev/null
+++ b/spec/lib/gitlab/background_migration/backfill_note_discussion_id_spec.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::BackfillNoteDiscussionId do
+  let(:migration) { described_class.new }
+  let(:notes_table) { table(:notes) }
+  let(:existing_discussion_id) { Digest::SHA1.hexdigest('test') }
+
+  before do
+    notes_table.create!(id: 1, noteable_type: 'Issue', noteable_id: 2, discussion_id: existing_discussion_id)
+    notes_table.create!(id: 2, noteable_type: 'Issue', noteable_id: 1, discussion_id: nil)
+    notes_table.create!(id: 3, noteable_type: 'MergeRequest', noteable_id: 1, discussion_id: nil)
+    notes_table.create!(id: 4, noteable_type: 'Commit', commit_id: RepoHelpers.sample_commit.id, discussion_id: nil)
+    notes_table.create!(id: 5, noteable_type: 'Issue', noteable_id: 2, discussion_id: nil)
+    notes_table.create!(id: 6, noteable_type: 'MergeRequest', noteable_id: 2, discussion_id: nil)
+  end
+
+  it 'updates records in the specified batch', :aggregate_failures do
+    migration.perform(1, 5)
+
+    expect(notes_table.where(discussion_id: nil).count).to eq(1)
+
+    expect(notes_table.find(1).discussion_id).to eq(existing_discussion_id)
+    notes_table.where(id: 2..5).each do |n|
+      expect(n.discussion_id).to match(/\A[0-9a-f]{40}\z/)
+    end
+  end
+end