Rules to not allow issue like in #605 , thanks to @bcomnes

.eslintrc

@@ -0,0 +1,140 @@
+{
+  "parser": "babel-eslint",
+  "env": {
+    "node": true,
+    "browser": false
+  },
+  "globals": {
+    "Package": true,
+    "Tinytest": true,
+    "Map": true,
+    "Promise": true,
+    "Npm": true,
+    "window": true,
+    "Worker": true,
+    "navigator": true
+  },
+  "ecmaFeatures": {
+    "arrowFunctions": true,
+    "blockBindings": true,
+    "classes": true,
+    "defaultParams": true,
+    "destructuring": true,
+    "forOf": true,
+    "generators": false,
+    "modules": true,
+    "objectLiteralComputedProperties": true,
+    "objectLiteralDuplicateProperties": false,
+    "objectLiteralShorthandMethods": true,
+    "objectLiteralShorthandProperties": true,
+    "spread": true,
+    "superInFunctions": true,
+    "templateStrings": true
+  },
+  "rules": {
+    "strict": [2, "never"],
+    "no-shadow": 2,
+    "no-shadow-restricted-names": 2,
+    "no-unused-vars": [2, {
+      "vars": "local",
+      "args": "after-used"
+    }],
+    "no-use-before-define": [2, "nofunc"],
+    "no-cond-assign": [2, "always"],
+    "no-console": 1,
+    "no-debugger": 1,
+    "no-alert": 1,
+    "no-constant-condition": 1,
+    "no-dupe-keys": 2,
+    "no-duplicate-case": 2,
+    "no-empty": 2,
+    "no-ex-assign": 2,
+    "no-extra-boolean-cast": 0,
+    "no-extra-semi": 2,
+    "no-func-assign": 2,
+    "no-inner-declarations": 2,
+    "no-invalid-regexp": 2,
+    "no-irregular-whitespace": 2,
+    "no-obj-calls": 2,
+    "no-sparse-arrays": 2,
+    "no-unreachable": 2,
+    "use-isnan": 2,
+    "block-scoped-var": 0,
+    "no-undef": "error",
+    "consistent-return": 2,
+    "consistent-this": ["error", "self"],
+    "curly": [2, "multi-line"],
+    "default-case": 2,
+    "dot-notation": [2, {
+      "allowKeywords": true
+    }],
+    "eqeqeq": 2,
+    "guard-for-in": 2,
+    "no-caller": 2,
+    "no-else-return": 2,
+    "no-eq-null": 2,
+    "no-eval": 2,
+    "no-extend-native": 2,
+    "no-extra-bind": 2,
+    "no-fallthrough": 2,
+    "no-floating-decimal": 2,
+    "no-implied-eval": 2,
+    "no-lone-blocks": 2,
+    "no-loop-func": 2,
+    "no-multi-str": 2,
+    "no-native-reassign": 2,
+    "no-new": 2,
+    "no-new-func": 2,
+    "no-new-wrappers": 2,
+    "no-octal": 2,
+    "no-octal-escape": 2,
+    "no-param-reassign": 2,
+    "no-proto": 2,
+    "no-redeclare": 2,
+    "no-return-assign": 2,
+    "no-script-url": 2,
+    "no-self-compare": 2,
+    "no-sequences": 2,
+    "no-throw-literal": 2,
+    "no-with": 2,
+    "wrap-iife": [2, "any"],
+    "yoda": 2,
+    "indent": [2, 2],
+    "brace-style": [2,
+      "1tbs", {
+      "allowSingleLine": true
+    }],
+    "quotes": [
+      2, "single", "avoid-escape"
+    ],
+    "camelcase": [2, {
+      "properties": "never"
+    }],
+    "comma-spacing": [2, {
+      "before": false,
+      "after": true
+    }],
+    "comma-style": [2, "last"],
+    "eol-last": 2,
+    "key-spacing": [2, {
+        "beforeColon": false,
+        "afterColon": true
+    }],
+    "no-multiple-empty-lines": [2, {
+      "max": 2
+    }],
+    "no-nested-ternary": 2,
+    "no-new-object": 2,
+    "no-array-constructor": 2,
+    "no-trailing-spaces": 2,
+    "no-underscore-dangle": 0,
+    "one-var": [2, "never"],
+    "padded-blocks": [2, "never"],
+    "semi": [2, "always"],
+    "semi-spacing": [2, {
+      "before": false,
+      "after": true
+    }],
+    "space-infix-ops": 2,
+  }
+}