Use jest for eslint (#98)

Closes #94

Tap into jest runners to run eslint too so you can do everything in a single
command. Also added is-ci-cli so you can just do "npm test" regardless of what
environment you're in.

.travis.yml

@@ -3,6 +3,7 @@ language: node_js
 node_js:
     - "8"
     - "10"
+    - "11"
     - "node"
 
 env:

jest.config.js

@@ -1,15 +1,22 @@
 module.exports = {
-  collectCoverage: true,
-  collectCoverageFrom: ['lib/index.js'],
-  coverageDirectory: './coverage',
-  coverageThreshold: {
-    global: {
-      branches: 100,
-      functions: 100,
-      lines: 100,
-      statements: 100,
+  projects: [{
+    displayName: 'test',
+    collectCoverage: true,
+    collectCoverageFrom: ['lib/index.js'],
+    coverageDirectory: './coverage',
+    coverageThreshold: {
+      global: {
+        branches: 100,
+        functions: 100,
+        lines: 100,
+        statements: 100,
+      },
     },
-  },
-  testEnvironment: 'node',
-  verbose: true,
+    testEnvironment: 'node',
+    verbose: true,
+  }, {
+    runner: 'jest-runner-eslint',
+    displayName: 'linter',
+  }],
+  watchPlugins: ['jest-runner-eslint/watch-fix'],
 };

package.json

@@ -5,8 +5,9 @@
   "main": "lib/index.js",
   "types": "lib/index.d.ts",
   "scripts": {
-    "lint": "eslint lib test --fix",
-    "test": "npm run lint && jest --ci",
+    "test": "is-ci 'test:ci' 'test:local'",
+    "test:local": "jest --watch",
+    "test:ci": "jest --ci",
     "benchmark": "node benchmarks/index"
   },
   "repository": {
@@ -35,13 +36,15 @@
     "artificial": "0.1.x",
     "benchmark": "2.1.4",
     "body-parser": "1.18.2",
-    "eslint": "4.19.x",
-    "eslint-config-airbnb-base": "12.1.x",
-    "eslint-plugin-import": "2.11.x",
+    "eslint": "5.x.x",
+    "eslint-config-airbnb-base": "13.x.x",
+    "eslint-plugin-import": "2.x.x",
     "expect": "23.x.x",
     "express": "next",
     "faker": "4.1.x",
-    "jest": "23.x.x"
+    "is-ci-cli": "^1.1.1",
+    "jest": "23.x.x",
+    "jest-runner-eslint": "^0.7.1"
   },
   "engines": {
     "node": ">=8.9.0"

test/celebrate.test.js

@@ -1,13 +1,13 @@
 /* eslint-env jest */
 const expect = require('expect');
+const { name, random, date } = require('faker');
 const {
   celebrate,
   Joi,
   errors,
   isCelebrate,
 } = require('../lib');
 
-const { name, random, date } = require('faker');
 
 describe('celebrate()', () => {
   describe.each`