Prettier (#1112)

Closes #1081

Author: leebyron

.eslintrc

@@ -3,7 +3,8 @@
 
   "plugins": [
     "babel",
-    "flowtype"
+    "flowtype",
+    "prettier"
   ],
 
   "env": {
@@ -39,6 +40,8 @@
   },
 
   "rules": {
+    "prettier/prettier": 2,
+
     "flowtype/space-after-type-colon": [2, "always"],
     "flowtype/space-before-type-colon": [2, "never"],
     "flowtype/space-before-generic-bracket": [2, "never"],
@@ -48,7 +51,6 @@
     "flowtype/use-flow-type": 2,
     "flowtype/semi": 2,
 
-    "array-bracket-spacing": [2, "always"],
     "arrow-parens": [2, "as-needed"],
     "arrow-spacing": 2,
     "block-scoped-var": 0,
@@ -70,7 +72,6 @@
     "eqeqeq": ["error", "smart"],
     "func-names": 0,
     "func-style": 0,
-    "generator-star-spacing": [2, {"before": false, "after": true}],
     "guard-for-in": 2,
     "handle-callback-err": [2, "error"],
     "id-length": 0,
@@ -82,7 +83,10 @@
     "linebreak-style": 2,
     "lines-around-comment": 0,
     "max-depth": 0,
-    "max-len": [2, 80, 4],
+    "max-len": [2, 80, {
+      "ignoreComments": true,
+      "ignoreStrings": true
+    }],
     "max-nested-callbacks": 0,
     "max-params": 0,
     "max-statements": 0,
@@ -194,20 +198,17 @@
     "object-shorthand": [2, "always"],
     "one-var": [2, "never"],
     "operator-assignment": [2, "always"],
-    "operator-linebreak": [2, "after"],
     "padded-blocks": 0,
     "prefer-const": 2,
     "prefer-reflect": 0,
     "prefer-spread": 0,
     "quote-props": [2, "as-needed", {"numbers": true}],
-    "quotes": [2, "single"],
     "radix": 2,
     "require-yield": 0,
     "semi": [2, "always"],
     "semi-spacing": [2, {"before": false, "after": true}],
     "sort-vars": 0,
     "space-before-blocks": [2, "always"],
-    "space-before-function-paren": [2, {"anonymous": "always", "named": "never"}],
     "space-in-parens": 0,
     "space-infix-ops": [2, {"int32Hint": false}],
     "space-unary-ops": [2, {"words": true, "nonwords": false}],

.prettierrc

@@ -0,0 +1,5 @@
+{
+  "parser": "flow",
+  "singleQuote": true,
+  "trailingComma": "all"
+}

CONTRIBUTING.md

@@ -69,6 +69,9 @@ This will watch the file system run any relevant lint, tests, and type checks au
 
 ## Coding Style
 
+This project uses [Prettier](https://prettier.io/) for standard formatting. To
+ensure your pull request matches the style guides, run `npm run prettier`.
+
 * 2 spaces for indentation (no tabs)
 * 80 character line length strongly preferred.
 * Prefer `'` over `"`

package.json

@@ -26,6 +26,7 @@
     "testonly": "babel-node ./node_modules/.bin/_mocha $npm_package_options_mocha",
     "t": "babel-node ./node_modules/.bin/_mocha --require ./resources/mocha-bootload",
     "lint": "eslint --rulesdir ./resources/lint src || (printf '\\033[33mTry: \\033[7m npm run lint -- --fix \\033[0m\\n' && exit 1)",
+    "prettier": "prettier --write 'src/**/*.js'",
     "check": "flow check",
     "check-cover": "for file in {src/*.js,src/**/*.js}; do echo $file; flow coverage $file; done",
     "build": "npm run build:clean && npm run build:npm && npm run build:npm-flow && npm run build:module && npm run build:module-flow",
@@ -62,9 +63,11 @@
     "eslint": "4.4.1",
     "eslint-plugin-babel": "4.1.2",
     "eslint-plugin-flowtype": "2.35.0",
+    "eslint-plugin-prettier": "^2.3.1",
     "flow-bin": "^0.58.0",
     "isparta": "4.0.0",
     "mocha": "3.5.0",
+    "prettier": "^1.8.2",
     "sane": "2.0.0"
   }
 }

src/__tests__/starWarsData.js

@@ -19,43 +19,43 @@ const luke = {
   type: 'Human',
   id: '1000',
   name: 'Luke Skywalker',
-  friends: [ '1002', '1003', '2000', '2001' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1002', '1003', '2000', '2001'],
+  appearsIn: [4, 5, 6],
   homePlanet: 'Tatooine',
 };
 
 const vader = {
   type: 'Human',
   id: '1001',
   name: 'Darth Vader',
-  friends: [ '1004' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1004'],
+  appearsIn: [4, 5, 6],
   homePlanet: 'Tatooine',
 };
 
 const han = {
   type: 'Human',
   id: '1002',
   name: 'Han Solo',
-  friends: [ '1000', '1003', '2001' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1000', '1003', '2001'],
+  appearsIn: [4, 5, 6],
 };
 
 const leia = {
   type: 'Human',
   id: '1003',
   name: 'Leia Organa',
-  friends: [ '1000', '1002', '2000', '2001' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1000', '1002', '2000', '2001'],
+  appearsIn: [4, 5, 6],
   homePlanet: 'Alderaan',
 };
 
 const tarkin = {
   type: 'Human',
   id: '1004',
   name: 'Wilhuff Tarkin',
-  friends: [ '1001' ],
-  appearsIn: [ 4 ],
+  friends: ['1001'],
+  appearsIn: [4],
 };
 
 const humanData = {
@@ -70,17 +70,17 @@ const threepio = {
   type: 'Droid',
   id: '2000',
   name: 'C-3PO',
-  friends: [ '1000', '1002', '1003', '2001' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1000', '1002', '1003', '2001'],
+  appearsIn: [4, 5, 6],
   primaryFunction: 'Protocol',
 };
 
 const artoo = {
   type: 'Droid',
   id: '2001',
   name: 'R2-D2',
-  friends: [ '1000', '1002', '1003' ],
-  appearsIn: [ 4, 5, 6 ],
+  friends: ['1000', '1002', '1003'],
+  appearsIn: [4, 5, 6],
   primaryFunction: 'Astromech',
 };
 
@@ -115,7 +115,7 @@ export type Droid = {
   name: string,
   friends: Array<string>,
   appearsIn: Array<number>,
-  primaryFunction: string
+  primaryFunction: string,
 };
 
 /**