1 files changed, 33 insertions, 0 deletions
diff --git a/spec/lib/gitlab/database/count_spec.rb b/spec/lib/gitlab/database/count_spec.rb
index 1e1749b9b14..b31856fd675 100644
--- a/spec/lib/gitlab/database/count_spec.rb
+++ b/spec/lib/gitlab/database/count_spec.rb
@@ -27,6 +27,39 @@ describe Gitlab::Database::Count do
     end
 
     context 'fallbacks' do
+      subject { described_class.approximate_counts(models, strategies: strategies) }
+
+      let(:strategies) do
+        [
+          double('s1', :enabled? => true, new: first_strategy),
+          double('s2', :enabled? => true, new: second_strategy)
+        ]
+      end
+
+      let(:first_strategy) { double('first strategy', count: {}) }
+      let(:second_strategy) { double('second strategy', count: {}) }
+
+      it 'gets results from first strategy' do
+        expect(strategies[0]).to receive(:new).with(models).and_return(first_strategy)
+        expect(first_strategy).to receive(:count)
+
+        subject
+      end
+
+      it 'gets more results from second strategy if some counts are missing' do
+        expect(first_strategy).to receive(:count).and_return({ Project => 3 })
+        expect(strategies[1]).to receive(:new).with([Identity]).and_return(second_strategy)
+        expect(second_strategy).to receive(:count).and_return({ Identity => 1 })
+
+        expect(subject).to eq({ Project => 3, Identity => 1 })
+      end
+
+      it 'does not get more results as soon as all counts are present' do
+        expect(first_strategy).to receive(:count).and_return({ Project => 3, Identity => 1 })
+        expect(strategies[1]).not_to receive(:new)
+
+        subject
+      end
     end
 
     context 'with PostgreSQL', :postgresql do