Set up prettier, husky, and eslint

.eslintrc.json

@@ -0,0 +1,25 @@
+{
+  "env": {
+    "browser": true,
+    "commonjs": true,
+    "es6": true
+  },
+  "extends": ["eslint:recommended", "prettier"],
+  "parserOptions": {
+    "ecmaVersion": 2018,
+    "sourceType": "module"
+  },
+  "plugins": ["prettier"],
+  "rules": {
+    "linebreak-style": ["error", "unix"],
+    "semi": ["error", "always"],
+    "valid-jsdoc": [
+      "error",
+      {
+        "requireReturn": false,
+        "requireReturnDescription": false,
+        "requireParamDescription": false
+      }
+    ]
+  }
+}

.prettierrc

@@ -0,0 +1,4 @@
+{
+  "singleQuote": true,
+  "trailingComma": "es5"
+}

package.json

@@ -16,12 +16,17 @@
     "babel-preset-es2015": "^6.22.0",
     "bluebird": "^3.5.0",
     "concurrently": "^3.5.0",
+    "eslint": "^5.2.0",
+    "eslint-config-prettier": "^2.9.0",
+    "eslint-plugin-prettier": "^2.6.2",
     "gh-pages": "^0.12.0",
+    "husky": "^0.14.3",
     "jsdoc": "^3.4.3",
-    "jshint": "^2.9.4",
     "live-server": "^1.2.0",
     "mocha": "^3.2.0",
     "nodemon": "^1.11.0",
+    "prettier": "^1.14.0",
+    "pretty-quick": "^1.6.0",
     "webpack": "2.5.1",
     "webpack-dev-server": "2.4.5"
   },
@@ -34,9 +39,12 @@
     "doc:view": "live-server dist/doc --port=9124",
     "doc:watch": "nodemon --exec \"npm run doc\" --watch src --watch ./ --ext js,md --ignore dist",
     "doc:live": "concurrently --kill-others \"npm run doc:watch\" \"npm run doc:view\"",
-    "lint": "jshint src",
+    "lint": "eslint src test webpack.*",
     "deploy": "npm run build && npm run doc && gh-pages -d dist -b gh-pages",
+    "precommit": "pretty-quick --staged && npm test && npm run lint",
+    "prepush": "npm test && npm run lint",
     "preversion": "npm run lint && npm test",
+    "prettier": "prettier '{src,test}/**/*.js' webpack.* --write",
     "postversion": "git push && git push --tags && npm run deploy && npm publish"
   },
   "files": [

src/bezier.js

@@ -41,10 +41,22 @@ import assign from 'object-assign';
 // port of webkit cubic bezier handling by http://www.netzgesta.de/dev/
 
 /**
+ * @param {number} t
+ * @param {number} p1x
+ * @param {number} p1y
+ * @param {number} p2x
+ * @param {number} p2y
+ * @param {number} duration
+ * @returns {Function}
  * @private
  */
 function cubicBezierAtTime(t, p1x, p1y, p2x, p2y, duration) {
-  let ax = 0, bx = 0, cx = 0, ay = 0, by = 0, cy = 0;
+  let ax = 0,
+    bx = 0,
+    cx = 0,
+    ay = 0,
+    by = 0,
+    cy = 0;
 
   const sampleCurveX = t => ((ax * t + bx) * t + cx) * t;
 
@@ -54,7 +66,7 @@ function cubicBezierAtTime(t, p1x, p1y, p2x, p2y, duration) {
 
   const solveEpsilon = duration => 1 / (200 * duration);
 
-  const fabs = n => n >= 0 ? n : 0 - n;
+  const fabs = n => (n >= 0 ? n : 0 - n);
 
   const solveCurveX = (x, epsilon) => {
     let t0, t1, t2, x2, d2, i;
@@ -120,7 +132,7 @@ function cubicBezierAtTime(t, p1x, p1y, p2x, p2y, duration) {
 // End ported code
 
 /**
- *  getCubicBezierTransition(x1, y1, x2, y2) -> Function
+ *  GetCubicBezierTransition(x1, y1, x2, y2) -> Function.
  *
  *  Generates a transition easing function that is compatible
  *  with WebKit's CSS transitions `-webkit-transition-timing-function`
@@ -133,13 +145,11 @@ function cubicBezierAtTime(t, p1x, p1y, p2x, p2y, duration) {
  *  @param {number} y1
  *  @param {number} x2
  *  @param {number} y2
- *  @return {function}
+ *  @return {Function}
  *  @private
  */
-const getCubicBezierTransition = (x1, y1, x2, y2) =>
-  pos =>
-    cubicBezierAtTime(pos, x1, y1, x2, y2, 1);
-
+const getCubicBezierTransition = (x1, y1, x2, y2) => pos =>
+  cubicBezierAtTime(pos, x1, y1, x2, y2, 1);
 
 /**
  * Create a Bezier easing function and attach it to {@link
@@ -157,21 +167,20 @@ const getCubicBezierTransition = (x1, y1, x2, y2) =>
  * attached to {@link shifty.Tweenable.formulas}.
  */
 export const setBezierFunction = (name, x1, y1, x2, y2) =>
-  Tweenable.formulas[name] =
-    assign(getCubicBezierTransition(x1, y1, x2, y2), {
-      displayName: name,
-      x1,
-      y1,
-      x2,
-      y2
-    });
+  (Tweenable.formulas[name] = assign(getCubicBezierTransition(x1, y1, x2, y2), {
+    displayName: name,
+    x1,
+    y1,
+    x2,
+    y2,
+  }));
 
 /**
  * `delete` an easing function from {@link shifty.Tweenable.formulas}.  Be
  * careful with this method, as it `delete`s whatever easing formula matches
  * `name` (which means you can delete standard Shifty easing functions).
  * @method shifty.unsetBezierFunction
  * @param {string} name The name of the easing function to delete.
- * @return {Boolean} Whether or not the functions was `delete`d.
+ * @return {boolean} Whether or not the functions was `delete`d.
  */
 export const unsetBezierFunction = name => delete Tweenable.formulas[name];

src/easing-functions.js

@@ -36,53 +36,48 @@
  * @type {Object.<shifty.easingFunction>}
  * @static
  */
+
 export const linear = pos => pos;
 
 export const easeInQuad = pos => Math.pow(pos, 2);
 
-export const easeOutQuad = pos => -(Math.pow((pos - 1), 2) - 1);
+export const easeOutQuad = pos => -(Math.pow(pos - 1, 2) - 1);
 
 export const easeInOutQuad = pos =>
-  (pos /= 0.5) < 1 ?
-    0.5 * Math.pow(pos,2) :
-    -0.5 * ((pos -= 2) * pos - 2);
+  (pos /= 0.5) < 1 ? 0.5 * Math.pow(pos, 2) : -0.5 * ((pos -= 2) * pos - 2);
 
 export const easeInCubic = pos => Math.pow(pos, 3);
 
-export const easeOutCubic = pos => Math.pow((pos - 1), 3) + 1;
+export const easeOutCubic = pos => Math.pow(pos - 1, 3) + 1;
 
 export const easeInOutCubic = pos =>
-  (pos /= 0.5) < 1 ?
-    0.5 * Math.pow(pos,3) :
-    0.5 * (Math.pow((pos - 2),3) + 2);
+  (pos /= 0.5) < 1 ? 0.5 * Math.pow(pos, 3) : 0.5 * (Math.pow(pos - 2, 3) + 2);
 
 export const easeInQuart = pos => Math.pow(pos, 4);
 
-export const easeOutQuart = pos => -(Math.pow((pos - 1), 4) - 1);
+export const easeOutQuart = pos => -(Math.pow(pos - 1, 4) - 1);
 
 export const easeInOutQuart = pos =>
-  (pos /= 0.5) < 1 ?
-    0.5 * Math.pow(pos,4) :
-    -0.5 * ((pos -= 2) * Math.pow(pos,3) - 2);
+  (pos /= 0.5) < 1
+    ? 0.5 * Math.pow(pos, 4)
+    : -0.5 * ((pos -= 2) * Math.pow(pos, 3) - 2);
 
 export const easeInQuint = pos => Math.pow(pos, 5);
 
-export const easeOutQuint = pos => Math.pow((pos - 1), 5) + 1;
+export const easeOutQuint = pos => Math.pow(pos - 1, 5) + 1;
 
 export const easeInOutQuint = pos =>
-  (pos /= 0.5) < 1 ?
-    0.5 * Math.pow(pos,5) :
-    0.5 * (Math.pow((pos - 2),5) + 2);
+  (pos /= 0.5) < 1 ? 0.5 * Math.pow(pos, 5) : 0.5 * (Math.pow(pos - 2, 5) + 2);
 
 export const easeInSine = pos => -Math.cos(pos * (Math.PI / 2)) + 1;
 
 export const easeOutSine = pos => Math.sin(pos * (Math.PI / 2));
 
 export const easeInOutSine = pos => -0.5 * (Math.cos(Math.PI * pos) - 1);
 
-export const easeInExpo = pos => (pos === 0) ? 0 : Math.pow(2, 10 * (pos - 1));
+export const easeInExpo = pos => (pos === 0 ? 0 : Math.pow(2, 10 * (pos - 1)));
 
-export const easeOutExpo = pos => (pos === 1) ? 1 : -Math.pow(2, -10 * pos) + 1;
+export const easeOutExpo = pos => (pos === 1 ? 1 : -Math.pow(2, -10 * pos) + 1);
 
 export const easeInOutExpo = pos => {
   if (pos === 0) {
@@ -94,30 +89,30 @@ export const easeInOutExpo = pos => {
   }
 
   if ((pos /= 0.5) < 1) {
-    return 0.5 * Math.pow(2,10 * (pos - 1));
+    return 0.5 * Math.pow(2, 10 * (pos - 1));
   }
 
   return 0.5 * (-Math.pow(2, -10 * --pos) + 2);
 };
 
-export const easeInCirc = pos => -(Math.sqrt(1 - (pos * pos)) - 1);
+export const easeInCirc = pos => -(Math.sqrt(1 - pos * pos) - 1);
 
-export const easeOutCirc = pos => Math.sqrt(1 - Math.pow((pos - 1), 2));
+export const easeOutCirc = pos => Math.sqrt(1 - Math.pow(pos - 1, 2));
 
 export const easeInOutCirc = pos =>
-  ((pos /= 0.5) < 1) ?
-    -0.5 * (Math.sqrt(1 - pos * pos) - 1) :
-    0.5 * (Math.sqrt(1 - (pos -= 2) * pos) + 1);
+  (pos /= 0.5) < 1
+    ? -0.5 * (Math.sqrt(1 - pos * pos) - 1)
+    : 0.5 * (Math.sqrt(1 - (pos -= 2) * pos) + 1);
 
 export const easeOutBounce = pos => {
-  if (pos < (1 / 2.75)) {
-    return (7.5625 * pos * pos);
-  } else if (pos < (2 / 2.75)) {
-    return (7.5625 * (pos -= (1.5 / 2.75)) * pos + 0.75);
-  } else if (pos < (2.5 / 2.75)) {
-    return (7.5625 * (pos -= (2.25 / 2.75)) * pos + 0.9375);
+  if (pos < 1 / 2.75) {
+    return 7.5625 * pos * pos;
+  } else if (pos < 2 / 2.75) {
+    return 7.5625 * (pos -= 1.5 / 2.75) * pos + 0.75;
+  } else if (pos < 2.5 / 2.75) {
+    return 7.5625 * (pos -= 2.25 / 2.75) * pos + 0.9375;
   } else {
-    return (7.5625 * (pos -= (2.625 / 2.75)) * pos + 0.984375);
+    return 7.5625 * (pos -= 2.625 / 2.75) * pos + 0.984375;
   }
 };
 
@@ -134,19 +129,20 @@ export const easeOutBack = pos => {
 export const easeInOutBack = pos => {
   let s = 1.70158;
   if ((pos /= 0.5) < 1) {
-    return 0.5 * (pos * pos * (((s *= (1.525)) + 1) * pos - s));
+    return 0.5 * (pos * pos * (((s *= 1.525) + 1) * pos - s));
   }
-  return 0.5 * ((pos -= 2) * pos * (((s *= (1.525)) + 1) * pos + s) + 2);
+  return 0.5 * ((pos -= 2) * pos * (((s *= 1.525) + 1) * pos + s) + 2);
 };
 
 export const elastic = pos =>
-  -1 * Math.pow(4,-8 * pos) * Math.sin((pos * 6 - 1) * (2 * Math.PI) / 2) + 1;
+  -1 * Math.pow(4, -8 * pos) * Math.sin(((pos * 6 - 1) * (2 * Math.PI)) / 2) +
+  1;
 
 export const swingFromTo = pos => {
   let s = 1.70158;
-  return ((pos /= 0.5) < 1) ?
-      0.5 * (pos * pos * (((s *= (1.525)) + 1) * pos - s)) :
-      0.5 * ((pos -= 2) * pos * (((s *= (1.525)) + 1) * pos + s) + 2);
+  return (pos /= 0.5) < 1
+    ? 0.5 * (pos * pos * (((s *= 1.525) + 1) * pos - s))
+    : 0.5 * ((pos -= 2) * pos * (((s *= 1.525) + 1) * pos + s) + 2);
 };
 
 export const swingFrom = pos => {
@@ -160,33 +156,33 @@ export const swingTo = pos => {
 };
 
 export const bounce = pos => {
-  if (pos < (1 / 2.75)) {
-    return (7.5625 * pos * pos);
-  } else if (pos < (2 / 2.75)) {
-    return (7.5625 * (pos -= (1.5 / 2.75)) * pos + 0.75);
-  } else if (pos < (2.5 / 2.75)) {
-    return (7.5625 * (pos -= (2.25 / 2.75)) * pos + 0.9375);
+  if (pos < 1 / 2.75) {
+    return 7.5625 * pos * pos;
+  } else if (pos < 2 / 2.75) {
+    return 7.5625 * (pos -= 1.5 / 2.75) * pos + 0.75;
+  } else if (pos < 2.5 / 2.75) {
+    return 7.5625 * (pos -= 2.25 / 2.75) * pos + 0.9375;
   } else {
-    return (7.5625 * (pos -= (2.625 / 2.75)) * pos + 0.984375);
+    return 7.5625 * (pos -= 2.625 / 2.75) * pos + 0.984375;
   }
 };
 
 export const bouncePast = pos => {
-  if (pos < (1 / 2.75)) {
-    return (7.5625 * pos * pos);
-  } else if (pos < (2 / 2.75)) {
-    return 2 - (7.5625 * (pos -= (1.5 / 2.75)) * pos + 0.75);
-  } else if (pos < (2.5 / 2.75)) {
-    return 2 - (7.5625 * (pos -= (2.25 / 2.75)) * pos + 0.9375);
+  if (pos < 1 / 2.75) {
+    return 7.5625 * pos * pos;
+  } else if (pos < 2 / 2.75) {
+    return 2 - (7.5625 * (pos -= 1.5 / 2.75) * pos + 0.75);
+  } else if (pos < 2.5 / 2.75) {
+    return 2 - (7.5625 * (pos -= 2.25 / 2.75) * pos + 0.9375);
   } else {
-    return 2 - (7.5625 * (pos -= (2.625 / 2.75)) * pos + 0.984375);
+    return 2 - (7.5625 * (pos -= 2.625 / 2.75) * pos + 0.984375);
   }
 };
 
 export const easeFromTo = pos =>
-  ((pos /= 0.5) < 1) ?
-    0.5 * Math.pow(pos,4) :
-    -0.5 * ((pos -= 2) * Math.pow(pos,3) - 2);
+  (pos /= 0.5) < 1
+    ? 0.5 * Math.pow(pos, 4)
+    : -0.5 * ((pos -= 2) * Math.pow(pos, 3) - 2);
 
 export const easeFrom = pos => Math.pow(pos, 4);
 

src/interpolate.js

@@ -11,7 +11,7 @@ mockTweenable._filterArgs = [];
  * specific frame of animation that {@link shifty.Tweenable#tween} does many times
  * over the course of a full tween.
  *
- *     import { interpolate } from 'shifty';
+ *     import { interpolate } from 'shifty';.
  *
  *     const interpolatedValues = interpolate({
  *         width: '100px',
@@ -45,9 +45,7 @@ mockTweenable._filterArgs = [];
  * increase all valid values of `position` to numbers between `0` and `1.5`.
  * @return {Object}
  */
-export const interpolate =
-  (from, to, position, easing, delay = 0) => {
-
+export const interpolate = (from, to, position, easing, delay = 0) => {
   const current = clone(from);
   const easingObject = composeEasingObject(from, easing);
 
@@ -58,8 +56,15 @@ export const interpolate =
   mockTweenable._applyFilter('tweenCreated');
   mockTweenable._applyFilter('beforeTween');
 
-  const interpolatedValues =
-    tweenProps(position, current, from, to, 1, delay, easingObject);
+  const interpolatedValues = tweenProps(
+    position,
+    current,
+    from,
+    to,
+    1,
+    delay,
+    easingObject
+  );
 
   // Transform data in interpolatedValues back into its original format
   mockTweenable._applyFilter('afterTween');