1 files changed, 34 insertions, 0 deletions
diff --git a/spec/migrations/clean_up_noteable_id_for_notes_on_commits_spec.rb b/spec/migrations/clean_up_noteable_id_for_notes_on_commits_spec.rb
new file mode 100644
index 00000000000..572b7dfd0c8
--- /dev/null
+++ b/spec/migrations/clean_up_noteable_id_for_notes_on_commits_spec.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require Rails.root.join('db', 'post_migrate', '20190313092516_clean_up_noteable_id_for_notes_on_commits.rb')
+
+describe CleanUpNoteableIdForNotesOnCommits, :migration do
+  let(:notes) { table(:notes) }
+
+  before do
+    notes.create!(noteable_type: 'Commit', commit_id: '3d0a182204cece4857f81c6462720e0ad1af39c9', noteable_id: 3, note: 'Test')
+    notes.create!(noteable_type: 'Commit', commit_id: '3d0a182204cece4857f81c6462720e0ad1af39c9', noteable_id: 3, note: 'Test')
+    notes.create!(noteable_type: 'Commit', commit_id: '3d0a182204cece4857f81c6462720e0ad1af39c9', noteable_id: 3, note: 'Test')
+
+    notes.create!(noteable_type: 'Issue', noteable_id: 1, note: 'Test')
+    notes.create!(noteable_type: 'MergeRequest', noteable_id: 1, note: 'Test')
+    notes.create!(noteable_type: 'Snippet', noteable_id: 1, note: 'Test')
+  end
+
+  it 'clears noteable_id for notes on commits' do
+    expect { migrate! }.to change { dirty_notes_on_commits.count }.from(3).to(0)
+  end
+
+  it 'does not clear noteable_id for other notes' do
+    expect { migrate! }.not_to change { other_notes.count }
+  end
+
+  def dirty_notes_on_commits
+    notes.where(noteable_type: 'Commit').where('noteable_id IS NOT NULL')
+  end
+
+  def other_notes
+    notes.where("noteable_type != 'Commit' AND noteable_id IS NOT NULL")
+  end
+end