interface: add eslint and update contrib docs

pkg/interface/.eslintrc.json

@@ -0,0 +1,147 @@
+{
+  "env": {
+    "browser": true,
+    "es6": true,
+    "node": true
+  },
+  "extends": [
+    "eslint:recommended",
+    "plugin:react/recommended"
+  ],
+  "settings": {
+    "react": {
+      "version": "^16.5.2"
+    }
+  },
+  "parser": "babel-eslint",
+  "parserOptions": {
+    "ecmaVersion": 10,
+    "requireConfigFile": false,
+    "sourceType": "module"
+  },
+  "root": true,
+  "rules": {
+    "array-bracket-spacing": ["error", "never"],
+    "arrow-parens": [
+      "error",
+      "as-needed",
+      {
+        "requireForBlockBody": true
+      }
+    ],
+    "arrow-spacing": "error",
+    "block-spacing": ["error", "always"],
+    "brace-style": ["error", "1tbs"],
+    "camelcase": [
+      "error",
+      {
+        "properties": "never"
+      }
+    ],
+    "comma-dangle": ["error", "never"],
+    "eol-last": ["error", "always"],
+    "func-name-matching": "error",
+    "indent": [
+      "off",
+      2,
+      {
+        "ArrayExpression": "off",
+        "SwitchCase": 1,
+        "CallExpression": {
+          "arguments": "off"
+        },
+        "FunctionDeclaration": {
+          "parameters": "off"
+        },
+        "FunctionExpression": {
+          "parameters": "off"
+        },
+        "MemberExpression": "off",
+        "ObjectExpression": "off",
+        "ImportDeclaration": "off"
+      }
+    ],
+    "handle-callback-err": "off",
+    "linebreak-style": ["error", "unix"],
+    "max-statements-per-line": [
+      "error",
+      {
+        "max": 1
+      }
+    ],
+    "new-cap": [
+      "error",
+      {
+        "newIsCap": true,
+        "capIsNew": false
+      }
+    ],
+    "new-parens": "error",
+    "no-buffer-constructor": "error",
+    "no-console": "off",
+    "no-extra-semi": "off",
+    "no-fallthrough": "off",
+    "no-func-assign": "off",
+    "no-implicit-coercion": "error",
+    "no-multi-assign": "error",
+    "no-multiple-empty-lines": [
+      "error",
+      {
+        "max": 1
+      }
+    ],
+    "no-nested-ternary": "error",
+    "no-param-reassign": "off",
+    "no-return-assign": "error",
+    "no-return-await": "off",
+    "no-shadow-restricted-names": "error",
+    "no-tabs": "error",
+    "no-trailing-spaces": "error",
+    "no-unused-vars": [
+      "error",
+      {
+        "vars": "all",
+        "args": "none",
+        "ignoreRestSiblings": false
+      }
+    ],
+    "no-use-before-define": [
+      "error",
+      {
+        "functions": false,
+        "classes": false
+      }
+    ],
+    "no-useless-escape": "off",
+    "no-var": "error",
+    "nonblock-statement-body-position": ["error", "below"],
+    "object-curly-spacing": ["error", "always"],
+    "padded-blocks": ["error", "never"],
+    "prefer-arrow-callback": "error",
+    "prefer-const": [
+      "error",
+      {
+        "destructuring": "all",
+        "ignoreReadBeforeAssign": true
+      }
+    ],
+    "prefer-template": "off",
+    "quotes": ["error", "single"],
+    "semi": ["error", "always"],
+    "spaced-comment": [
+      "error",
+      "always",
+      {
+        "exceptions": ["!"]
+      }
+    ],
+    "space-before-blocks": "error",
+    "unicode-bom": ["error", "never"],
+    "valid-jsdoc": "error",
+    "wrap-iife": ["error", "inside"],
+    "react/jsx-closing-bracket-location": 1,
+    "react/jsx-tag-spacing": 1,
+    "react/jsx-max-props-per-line": ["error", { "maximum": 1, "when": "multiline" }],
+    "react/prop-types": 0
+  }
+}

pkg/interface/CONTRIBUTING.md

@@ -36,6 +36,23 @@ Please also ensure your pull request fits our standards for
 [arvo]: /pkg/arvo
 [interface]:/pkg/interface
 
+## Linting
+
+The Urbit interface uses Eslint to lint the JavaScript code. To install the
+linter and for usage through the command, do the following:
+```bash
+$ cd ./pkg/interface
+$ npm install
+$ npm run lint
+```
+
+To use the linter, run npm scripts
+```bash
+$ npm run lint # lints all files in `interface`
+$ npm run lint-file ./chat/**/*.js # lints all .js files in `interface/chat`
+$ npm run lint-file ./chat/src/index.js # lints a single chosen file
+```
+
 ### Gall
 
 Presently, Gall documentation is still in [progress][gall], but a good

pkg/interface/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "interface",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "dependencies": {},
+  "devDependencies": {
+    "babel-eslint": "^10.1.0",
+    "eslint": "^6.8.0",
+    "eslint-plugin-react": "^7.19.0"
+  },
+  "scripts": {
+    "lint": "eslint ./**/*.js",
+    "lint-file": "eslint",
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "ISC"
+}