1 files changed, 45 insertions, 0 deletions
diff --git a/spec/lib/gitlab/background_migration/batching_strategies/primary_key_batching_strategy_spec.rb b/spec/lib/gitlab/background_migration/batching_strategies/primary_key_batching_strategy_spec.rb
new file mode 100644
index 00000000000..8febe850e04
--- /dev/null
+++ b/spec/lib/gitlab/background_migration/batching_strategies/primary_key_batching_strategy_spec.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::BatchingStrategies::PrimaryKeyBatchingStrategy, '#next_batch' do
+  let(:batching_strategy) { described_class.new }
+  let(:namespaces) { table(:namespaces) }
+
+  let!(:namespace1) { namespaces.create!(name: 'batchtest1', path: 'batch-test1') }
+  let!(:namespace2) { namespaces.create!(name: 'batchtest2', path: 'batch-test2') }
+  let!(:namespace3) { namespaces.create!(name: 'batchtest3', path: 'batch-test3') }
+  let!(:namespace4) { namespaces.create!(name: 'batchtest4', path: 'batch-test4') }
+
+  context 'when starting on the first batch' do
+    it 'returns the bounds of the next batch' do
+      batch_bounds = batching_strategy.next_batch(:namespaces, :id, batch_min_value: namespace1.id, batch_size: 3)
+
+      expect(batch_bounds).to eq([namespace1.id, namespace3.id])
+    end
+  end
+
+  context 'when additional batches remain' do
+    it 'returns the bounds of the next batch' do
+      batch_bounds = batching_strategy.next_batch(:namespaces, :id, batch_min_value: namespace2.id, batch_size: 3)
+
+      expect(batch_bounds).to eq([namespace2.id, namespace4.id])
+    end
+  end
+
+  context 'when on the final batch' do
+    it 'returns the bounds of the next batch' do
+      batch_bounds = batching_strategy.next_batch(:namespaces, :id, batch_min_value: namespace4.id, batch_size: 3)
+
+      expect(batch_bounds).to eq([namespace4.id, namespace4.id])
+    end
+  end
+
+  context 'when no additional batches remain' do
+    it 'returns nil' do
+      batch_bounds = batching_strategy.next_batch(:namespaces, :id, batch_min_value: namespace4.id + 1, batch_size: 1)
+
+      expect(batch_bounds).to be_nil
+    end
+  end
+end