Add eslint

Author: jdesrosiers

.eslintrc

@@ -0,0 +1,34 @@
+{
+  "root": true,
+  "env": {
+    "es6": true,
+    "node": true
+  },
+  "parserOptions": {
+    "ecmaVersion": 2020,
+    "sourceType": "module"
+  },
+  "extends": [
+    "eslint:recommended",
+    "plugin:import/recommended"
+  ],
+  "plugins": ["import"],
+  "rules": {
+    "array-bracket-spacing": "error",
+    "arrow-parens": "error",
+    "comma-dangle": "error",
+    "dot-location": ["error", "property"],
+    "eol-last": "error",
+    "generator-star-spacing": ["error", { "before": false, "after": true }],
+    "indent": ["error", 2, { "ignoreComments": true, "SwitchCase": 1 }],
+    "linebreak-style": "error",
+    "no-trailing-spaces": "error",
+    "no-unused-vars": ["error", { "argsIgnorePattern": "_.*" }],
+    "prefer-const": ["error", { "destructuring": "all" }],
+    "semi": "error",
+    "quotes": ["error", "double", { "allowTemplateLiterals": true }]
+  },
+  "settings": {
+    "import/resolver": "node"
+  }
+}

.gitignore

@@ -10,3 +10,5 @@ relative-json-pointer.txt
 
 package-lock.json
 node_modules/
+
+.env

package.json

@@ -5,6 +5,7 @@
   "type": "module",
   "main": "index.js",
   "scripts": {
+    "lint": "eslint build/",
     "build": "npm run build-core && npm run build-validation",
     "build-core": "node build/build.js < jsonschema-core.md > jsonschema-core.html",
     "build-validation": "node build/build.js < jsonschema-validation.md > jsonschema-validation.html"
@@ -27,6 +28,9 @@
     "vfile-reporter": "^8.0.0"
   },
   "devDependencies": {
-    "dotenv": "^16.3.1"
+    "dotenv": "*",
+    "eslint": "*",
+    "eslint-import-resolver-node": "*",
+    "eslint-plugin-import": "*"
   }
 }