Migrate prometheus_metrics specs to Jest

Migrate spec/javascripts/prometheus_metrics specs from Karma to Jest.

spec/frontend/prometheus_metrics/custom_metrics_spec.js

@@ -2,7 +2,7 @@ import MockAdapter from 'axios-mock-adapter';
 import CustomMetrics from '~/prometheus_metrics/custom_metrics';
 import axios from '~/lib/utils/axios_utils';
 import PANEL_STATE from '~/prometheus_metrics/constants';
-import metrics from './mock_data';
+import { metrics1 as metrics } from './mock_data';
 
 describe('PrometheusMetrics', () => {
   const FIXTURE = 'services/prometheus/prometheus_service.html';

spec/frontend/prometheus_metrics/mock_data.js

-const metrics = [
+export const metrics1 = [
   {
     edit_path: '/root/prometheus-test/prometheus/metrics/3/edit',
     id: 3,
@@ -19,4 +19,44 @@ const metrics = [
   },
 ];
 
-export default metrics;
+export const metrics2 = [
+  {
+    group: 'Kubernetes',
+    priority: 1,
+    active_metrics: 4,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'HAProxy',
+    priority: 2,
+    active_metrics: 3,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'Apache',
+    priority: 3,
+    active_metrics: 5,
+    metrics_missing_requirements: 0,
+  },
+];
+
+export const missingVarMetrics = [
+  {
+    group: 'Kubernetes',
+    priority: 1,
+    active_metrics: 4,
+    metrics_missing_requirements: 0,
+  },
+  {
+    group: 'HAProxy',
+    priority: 2,
+    active_metrics: 3,
+    metrics_missing_requirements: 1,
+  },
+  {
+    group: 'Apache',
+    priority: 3,
+    active_metrics: 5,
+    metrics_missing_requirements: 3,
+  },
+];

spec/javascripts/prometheus_metrics/prometheus_metrics_spec.js → spec/frontend/prometheus_metrics/prometheus_metrics_spec.js

@@ -2,7 +2,7 @@ import MockAdapter from 'axios-mock-adapter';
 import axios from '~/lib/utils/axios_utils';
 import PrometheusMetrics from '~/prometheus_metrics/prometheus_metrics';
 import PANEL_STATE from '~/prometheus_metrics/constants';
-import { metrics, missingVarMetrics } from './mock_data';
+import { metrics2 as metrics, missingVarMetrics } from './mock_data';
 
 describe('PrometheusMetrics', () => {
   const FIXTURE = 'services/prometheus/prometheus_service.html';
@@ -126,7 +126,7 @@ describe('PrometheusMetrics', () => {
     }
 
     beforeEach(() => {
-      spyOn(axios, 'get').and.callThrough();
+      jest.spyOn(axios, 'get');
 
       prometheusMetrics = new PrometheusMetrics('.js-prometheus-metrics-monitoring');
 
@@ -145,7 +145,7 @@ describe('PrometheusMetrics', () => {
       expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeFalsy();
       expect(axios.get).toHaveBeenCalledWith(prometheusMetrics.activeMetricsEndpoint);
 
-      setTimeout(() => {
+      setImmediate(() => {
         expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
         done();
       });
@@ -156,7 +156,7 @@ describe('PrometheusMetrics', () => {
 
       prometheusMetrics.loadActiveMetrics();
 
-      setTimeout(() => {
+      setImmediate(() => {
         expect(prometheusMetrics.$monitoredMetricsLoading.hasClass('hidden')).toBeTruthy();
         expect(prometheusMetrics.$monitoredMetricsEmpty.hasClass('hidden')).toBeFalsy();
         done();
@@ -164,12 +164,12 @@ describe('PrometheusMetrics', () => {
     });
 
     it('should populate metrics list once response is loaded', done => {
-      spyOn(prometheusMetrics, 'populateActiveMetrics');
+      jest.spyOn(prometheusMetrics, 'populateActiveMetrics').mockImplementation();
       mockSuccess();
 
       prometheusMetrics.loadActiveMetrics();
 
-      setTimeout(() => {
+      setImmediate(() => {
         expect(prometheusMetrics.populateActiveMetrics).toHaveBeenCalledWith(metrics);
         done();
       });

spec/javascripts/prometheus_metrics/mock_data.js

-export const metrics = [
-  {
-    group: 'Kubernetes',
-    priority: 1,
-    active_metrics: 4,
-    metrics_missing_requirements: 0,
-  },
-  {
-    group: 'HAProxy',
-    priority: 2,
-    active_metrics: 3,
-    metrics_missing_requirements: 0,
-  },
-  {
-    group: 'Apache',
-    priority: 3,
-    active_metrics: 5,
-    metrics_missing_requirements: 0,
-  },
-];
-
-export const missingVarMetrics = [
-  {
-    group: 'Kubernetes',
-    priority: 1,
-    active_metrics: 4,
-    metrics_missing_requirements: 0,
-  },
-  {
-    group: 'HAProxy',
-    priority: 2,
-    active_metrics: 3,
-    metrics_missing_requirements: 1,
-  },
-  {
-    group: 'Apache',
-    priority: 3,
-    active_metrics: 5,
-    metrics_missing_requirements: 3,
-  },
-];