Refactor is* functions

package.json

@@ -1,22 +1,18 @@
 {
   "name": "trimkit",
-  "version": "1.0.2",
+  "version": "1.0.3",
   "description": "Javascript and DOM abstractions for smaller minifiable code",
-  "main": "lib/index.js",
-  "jsnext:main": "src/index.js",
+  "main": "dist/trimkit.js",
+  "module": "dist/trimkit.js",
   "files": [
-    "dist",
-    "lib",
-    "src"
+    "dist/"
   ],
   "scripts": {
     "lint": "eslint src",
-    "clean": "rimraf dist lib",
-    "build:lib": "NODE_ENV=production babel src --presets=\"stage-0,es2015\" --out-dir lib",
-    "build:umd": "npm run build:lib && NODE_ENV=production rollup -c",
-    "build:umd:min": "npm run build:umd && uglifyjs -m --screw-ie8 -c -o dist/trimkit.min.js dist/trimkit.js",
-    "build:umd:gzip": "npm run build:umd:min && gzip -c9 dist/trimkit.min.js > dist/trimkit.min.js.gz",
-    "build": "npm run build:umd:gzip && ls -l dist/",
+    "clean": "rimraf dist",
+    "build:umd": "rollup -c rollup.config.js && uglifyjs -m --screw-ie8 -c -o dist/trimkit.min.js dist/trimkit.js",
+    "build:umd:zip": "npm run build:umd && gzip -c9 dist/trimkit.min.js > dist/trimkit.min.js.gz && gzip -c9 dist/trimkit.min.mjs > dist/trimkit.min.mjs.gz",
+    "build": "npm run build:umd:zip && ls -l dist/",
     "prepublish": "npm run clean && npm run build"
   },
   "repository": {
@@ -40,10 +36,10 @@
     "babel-preset-es2015-rollup": "3.0.0",
     "babel-preset-stage-0": "6.16.0",
     "eslint": "3.2.0",
-    "eslint-plugin-flowtype": "2.29.1",
     "rimraf": "2.5.4",
+    "rollup": "0.66.6",
     "rollup-plugin-babel": "2.7.1",
-    "rollup-plugin-json": "2.1.0",
-    "uglifyjs": "2.4.10"
+    "rollup-plugin-esmin": "0.1.3",
+    "uglify-es": "3.3.9"
   }
 }

rollup.config.js

@@ -1,10 +1,44 @@
-import json from 'rollup-plugin-json';
+import esmin from 'rollup-plugin-esmin';
+import babel from 'rollup-plugin-babel';
+import pkg from './package.json';
 
-
-export default {
-    entry: 'src/index.js',
-    format: 'umd',
-    moduleName: 'Trimkit',
-    plugins: [ json() ],
-    dest: 'dist/trimkit.js'
+const config = {
+    input: 'src/index.js',
+    output: {
+        file: pkg.module,
+        format: 'es'
+    }
 };
+
+export default [
+    // trimkit.mjs
+    config,
+
+    // trimkit.min.mjs
+    {
+        ...config,
+        output: {
+            ...config.output,
+            file: 'dist/trimkit.min.mjs'
+        },
+        plugins: [ esmin({
+            overrides: {
+                sourceType: 'module'
+            }
+        }) ]
+    },
+
+    // trimkit.js
+    {
+        ...config,
+        output: {
+            format: 'umd',
+            file: 'dist/trimkit.js',
+            name: 'trimkit'
+        },
+        plugins: [
+            babel({ sourceType: 'module' })
+        ]
+
+    }
+]

src/index.js

@@ -1,4 +1,4 @@
-// Copyright (c) 2016 Timothy Farrell
+// Copyright (c) 2018 Timothy Farrell
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -48,29 +48,31 @@ export const ObjectKeys = Object.keys;
 // Size saved after: ceil(20 / 7) = 3 usages
 export const DOMDocument = self.document;
 
-// ES5 output: function a(b){return"function"===typeof b};
+const isType = str => obj => typeof obj === 'function';
+
+// ES5 output A: var c=(function(t){return function a(b){return t===typeof b}})('function');
+// ES5 output B: var c=a('function');
 // Invocation comparison: typeof a==='function' ~~~ a(b)
 // Size delta per invocation: 21 - 4 = 17 bytes
-// Size saved after: ceil(43 / 17) = 3 usages
-export function isFunction(obj) {
-    return typeof obj === 'function';
-}
+// Size saved after (A): ceil(75 / 17) = 5 usages
+// Size saved after (B): ceil(20 / 17) = 2 usages
+export const isFunction = isType('function');
 
-// ES5 output: function a(b){return"string"===typeof b};
+// ES5 output A: var c=(function(t){return function a(b){return t===typeof b}})('string');
+// ES5 output B: var c=a('string');
 // Invocation comparison: typeof a==='string' ~~~ a(b)
 // Size delta per invocation: 19 - 4 = 15 bytes
-// Size saved after: ceil(41 / 15) = 3 usages
-export function isString(obj) {
-    return typeof obj === 'string';
-}
+// Size saved after (A): ceil(73 / 15) = 5 usages
+// Size saved after (B): ceil(18 / 15) = 2 usages
+export const isString = isType('string');
 
-// ES5 output: function a(b){return"number"===typeof b};
+// ES5 output A: var c=(function(t){return function a(b){return t===typeof b}})('number');
+// ES5 output B: var c=a('number');
 // Invocation comparison: typeof a==='number' ~~~ a(b)
 // Size delta per invocation: 19 - 4 = 15 bytes
-// Size saved after: ceil(41 / 15) = 3 usages
-export function isNumber(obj) {
-    return typeof obj === 'number';
-}
+// Size saved after (A): ceil(73 / 15) = 5 usages
+// Size saved after (B): ceil(18 / 15) = 2 usages
+export const isNumber = isType('number');
 
 // ES5 declaration: var a=null;
 // Invocation comparison: null ~~~ a