Add linting configuration.

Author: Robert Jackson

.eslintignore

@@ -0,0 +1 @@
+/fixtures/

.eslintrc.js

@@ -0,0 +1,23 @@
+module.exports = {
+  root: true,
+  extends: ['eslint:recommended', 'prettier', 'plugin:node/recommended'],
+  plugins: ['prettier', 'node'],
+  parserOptions: {
+    ecmaVersion: 2017,
+  },
+  env: {
+    node: true,
+  },
+  rules: {
+    'prettier/prettier': 'error',
+  },
+
+  overrides: [
+    {
+      files: ['tests/**/*.js'],
+      env: {
+        jest: true
+      }
+    }
+  ]
+};

.prettierrc

@@ -0,0 +1,5 @@
+{
+  "singleQuote": true,
+  "trailingComma": "es5",
+  "printWidth": 100
+}

package.json

@@ -4,7 +4,12 @@
     "@babel/preset-env": "^7.0.0-beta.42",
     "babel-core": "^6.26.0",
     "babel-preset-env": "^1.6.1",
-    "jest": "^21.0.0"
+    "eslint": "^4.19.1",
+    "eslint-config-prettier": "^2.9.0",
+    "eslint-plugin-node": "^6.0.1",
+    "eslint-plugin-prettier": "^2.6.0",
+    "jest": "^21.0.0",
+    "prettier": "^1.12.1"
   },
   "name": "babel-plugin-debug-macros",
   "version": "0.2.0-beta.2",