Fix statistics records trimming

tests/Queue/StatisticsTest.js.ts

@@ -0,0 +1,35 @@
+import { it, describe } from 'mocha';
+import { expect } from 'chai';
+
+import { ActionStatistics, Statistics, StatisticsStorageInterface } from '../../src/Statistics';
+
+class MemoryStatisticsStorage implements StatisticsStorageInterface {
+    stat: ActionStatistics = {};
+
+    getActionStatistics(): ActionStatistics {
+        return this.stat;
+    }
+
+    setActionStatistics(statistics: ActionStatistics): void {
+        this.stat = statistics;
+    }
+}
+
+describe('Statistics', function() {
+    it('Can save statistics item', function() {
+        const storage = new MemoryStatisticsStorage();
+        const statistics = new Statistics(storage);
+        statistics.incrementAction(1588408294);
+        expect(Object.keys(statistics.getActionStatistics())).to.has.lengthOf(1);
+    });
+
+    it('Can trim statistics', function() {
+        const storage = new MemoryStatisticsStorage();
+        const statistics = new Statistics(storage);
+        const baseTime = 1588408294;
+        for (let i = 0; i < 120; ++i) {
+            statistics.incrementAction(baseTime + 3600 * i);
+        }
+        expect(Object.keys(statistics.getActionStatistics())).to.has.lengthOf(Statistics.keepRecords);
+    });
+});