Give an example of e2e test

Author: flochaz

packages/metrics/.eslintrc.json

@@ -144,7 +144,7 @@
       "error",
       {
         "devDependencies": [
-          "**/test/**",
+          "**/tests/**",
           "**/build-tools/**"
         ],
         "optionalDependencies": false,

packages/metrics/jest.config.js

@@ -1,35 +1,23 @@
 module.exports = {
-  'preset': 'ts-jest',
-  'transform': {
+  runner: 'groups',
+  preset: 'ts-jest',
+  transform: {
     '^.+\\.ts?$': 'ts-jest',
   },
-  moduleFileExtensions: [ 'js', 'ts' ],
-  'collectCoverageFrom': [
-    '**/src/**/*.ts',
-    '!**/node_modules/**',
-  ],
-  'testMatch': ['**/?(*.)+(spec|test).ts'],
-  'roots': [
-    '<rootDir>/src',
-    '<rootDir>/tests',
-  ],
-  'testPathIgnorePatterns': [
-    '/node_modules/',
-  ],
-  'testEnvironment': 'node',
-  'coveragePathIgnorePatterns': [
-    '/node_modules/',
-  ],
-  'coverageThreshold': {
-    'global': {
-      'statements': 100,
-      'branches': 100,
-      'functions': 100,
-      'lines': 100,
+  moduleFileExtensions: ['js', 'ts'],
+  collectCoverageFrom: ['**/src/**/*.ts', '!**/node_modules/**'],
+  testMatch: ['**/?(*.)+(spec|test).ts'],
+  roots: ['<rootDir>/src', '<rootDir>/tests'],
+  testPathIgnorePatterns: ['/node_modules/'],
+  testEnvironment: 'node',
+  coveragePathIgnorePatterns: ['/node_modules/'],
+  coverageThreshold: {
+    global: {
+      statements: 100,
+      branches: 100,
+      functions: 100,
+      lines: 100,
     },
   },
-  'coverageReporters': [
-    'json-summary',
-    'text',
-    'lcov' ],
-};
+  coverageReporters: ['json-summary', 'text', 'lcov'],
+};