Forgot to lint again

tests/metrics.test.js

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+const {
+  incrementCounter,
+  setGauge,
+  recordHistogram,
+  getMetrics,
+  resetMetrics
+} = require('../src/utils/metrics');
+
+describe('Metrics Utility', () => {
+  beforeEach(() => {
+    resetMetrics();
+  });
+
+  describe('incrementCounter', () => {
+    it('should increment a counter', () => {
+      incrementCounter('test_counter');
+      incrementCounter('test_counter');
+
+      const metrics = getMetrics();
+      const counter = metrics.counters.find(c => c.name === 'test_counter');
+
+      expect(counter).toBeDefined();
+      expect(counter.value).toBe(2);
+    });
+
+    it('should handle counters with labels', () => {
+      incrementCounter('http_requests', { method: 'GET' });
+      incrementCounter('http_requests', { method: 'POST' });
+      incrementCounter('http_requests', { method: 'GET' });
+
+      const metrics = getMetrics();
+      const getCounter = metrics.counters.find(c =>
+        c.name === 'http_requests' && c.labels.method === 'GET'
+      );
+      const postCounter = metrics.counters.find(c =>
+        c.name === 'http_requests' && c.labels.method === 'POST'
+      );
+
+      expect(getCounter.value).toBe(2);
+      expect(postCounter.value).toBe(1);
+    });
+  });
+
+  describe('setGauge', () => {
+    it('should set a gauge value', () => {
+      setGauge('memory_usage', 85.5);
+
+      const metrics = getMetrics();
+      const gauge = metrics.gauges.find(g => g.name === 'memory_usage');
+
+      expect(gauge).toBeDefined();
+      expect(gauge.value).toBe(85.5);
+    });
+
+    it('should update existing gauge values', () => {
+      setGauge('cpu_usage', 50);
+      setGauge('cpu_usage', 75);
+
+      const metrics = getMetrics();
+      const gauge = metrics.gauges.find(g => g.name === 'cpu_usage');
+
+      expect(gauge.value).toBe(75);
+    });
+  });
+
+  describe('recordHistogram', () => {
+    it('should record histogram values', () => {
+      recordHistogram('response_time', 100);
+      recordHistogram('response_time', 150);
+      recordHistogram('response_time', 200);
+
+      const metrics = getMetrics();
+      const histogram = metrics.histograms.find(h => h.name === 'response_time');
+
+      expect(histogram).toBeDefined();
+      expect(histogram.count).toBe(3);
+      expect(histogram.sum).toBe(450);
+      expect(histogram.average).toBe(150);
+      expect(histogram.min).toBe(100);
+      expect(histogram.max).toBe(200);
+    });
+  });
+
+  describe('getMetrics', () => {
+    it('should return all metrics with runtime info', () => {
+      incrementCounter('test_counter');
+      setGauge('test_gauge', 42);
+      recordHistogram('test_histogram', 100);
+
+      const metrics = getMetrics();
+
+      expect(metrics).toHaveProperty('counters');
+      expect(metrics).toHaveProperty('gauges');
+      expect(metrics).toHaveProperty('histograms');
+      expect(metrics).toHaveProperty('runtime');
+      expect(metrics).toHaveProperty('timestamp');
+
+      expect(metrics.counters).toHaveLength(1);
+      expect(metrics.gauges).toHaveLength(1);
+      expect(metrics.histograms).toHaveLength(1);
+
+      expect(metrics.runtime).toHaveProperty('uptime_seconds');
+      expect(metrics.runtime).toHaveProperty('memory_usage_bytes');
+    });
+  });
+
+  describe('resetMetrics', () => {
+    it('should clear all metrics', () => {
+      incrementCounter('test_counter');
+      setGauge('test_gauge', 42);
+      recordHistogram('test_histogram', 100);
+
+      resetMetrics();
+
+      const metrics = getMetrics();
+      expect(metrics.counters).toHaveLength(0);
+      expect(metrics.gauges).toHaveLength(0);
+      expect(metrics.histograms).toHaveLength(0);
+    });
+  });
+});