Add tests for events_for_category

lib/gitlab/usage_data_counters/hll_redis_counter.rb

@@ -53,8 +53,10 @@ module Gitlab
           Gitlab::Redis::HLL.count(keys: keys)
         end
 
+        # @param category [String] the category name
+        # @return [Array<String>] list of event names for given category
         def events_for_category(category)
-          known_events.select { |event| event[:category] == category }.map { |event| event[:name] }
+          known_events.select { |event| event[:category] == category.to_s }.map { |event| event[:name] }
         end
 
         private

spec/lib/gitlab/usage_data_counters/hll_redis_counter_spec.rb

@@ -43,6 +43,12 @@ RSpec.describe Gitlab::UsageDataCounters::HLLRedisCounter, :clean_gitlab_redis_s
     Timecop.freeze(reference_time) { example.run }
   end
 
+  describe '.events_for_category' do
+    it 'gets the event names for given category' do
+      expect(described_class.events_for_category(:analytics)).to contain_exactly(weekly_event, daily_event)
+    end
+  end
+
   describe '.track_event' do
     it "raise error if metrics don't have same aggregation" do
       expect { described_class.track_event(entity1, different_aggregation, Date.current) } .to raise_error(Gitlab::UsageDataCounters::HLLRedisCounter::UnknownAggregation)