Add tests for Redis HLL add and count

spec/lib/gitlab/redis/hll_spec.rb

@@ -4,6 +4,7 @@ require 'spec_helper'
 
 RSpec.describe Gitlab::Redis::HLL, :clean_gitlab_redis_shared_state do
   describe '.add' do
+    context 'when checking key format' do
       it 'raise an error when using an invalid key format' do
         expect { described_class.add(key: 'test', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::HLL::KeyFormatError)
         expect { described_class.add(key: 'test-{metric', value: 1, expiry: 1.day) }.to raise_error(Gitlab::Redis::HLL::KeyFormatError)
@@ -18,4 +19,42 @@ RSpec.describe Gitlab::Redis::HLL, :clean_gitlab_redis_shared_state do
         expect { described_class.add(key: 'i_{analytics}_dev_ops_score-2020-32', value: 1, expiry: 1.day) }.not_to raise_error
       end
     end
+  end
+
+  describe 'counts correct data for expand_vulnerabilities event' do
+    before do
+      described_class.add(key: '2020-32-{expand_vulnerabilities}', value: "user_id_1", expiry: 1.day)
+      described_class.add(key: '2020-32-{expand_vulnerabilities}', value: "user_id_1", expiry: 1.day)
+      described_class.add(key: '2020-32-{expand_vulnerabilities}', value: "user_id_2", expiry: 1.day)
+      described_class.add(key: '2020-32-{expand_vulnerabilities}', value: "user_id_3", expiry: 1.day)
+
+      described_class.add(key: '2020-33-{expand_vulnerabilities}', value: "user_id_3", expiry: 1.day)
+      described_class.add(key: '2020-33-{expand_vulnerabilities}', value: "user_id_3", expiry: 1.day)
+
+      described_class.add(key: '2020-34-{expand_vulnerabilities}', value: "user_id_3", expiry: 1.day)
+      described_class.add(key: '2020-34-{expand_vulnerabilities}', value: "user_id_2", expiry: 1.day)
+    end
+
+    it 'has 3 distinct users for weeks 32, 33, 34' do
+      expect(described_class.count(keys: ['2020-32-{expand_vulnerabilities}', '2020-33-{expand_vulnerabilities}', '2020-34-{expand_vulnerabilities}'])).to eq(3)
+    end
+
+    it 'has 3 distinct users for weeks 32, 33' do
+      expect(described_class.count(keys: ['2020-32-{expand_vulnerabilities}', '2020-33-{expand_vulnerabilities}'])).to eq(3)
+    end
+
+    it 'has 2 distinct users for weeks 33, 34' do
+      expect(described_class.count(keys: ['2020-33-{expand_vulnerabilities}', '2020-34-{expand_vulnerabilities}'])).to eq(2)
+    end
+
+    it 'has one distinct user for weel 33' do
+      expect(described_class.count(keys: ['2020-33-{expand_vulnerabilities}'])).to eq(1)
+    end
+
+    it 'has 4 distinct users when one different user has an action on week 34' do
+      described_class.add(key: '2020-34-{expand_vulnerabilities}', value: "user_id_4", expiry: 29.days)
+
+      expect(described_class.count(keys: ['2020-32-{expand_vulnerabilities}', '2020-33-{expand_vulnerabilities}', '2020-34-{expand_vulnerabilities}'])).to eq(4)
+    end
+  end
 end