Use Rollup for building project

Closes #3.

.babelrc

@@ -1,3 +1,3 @@
 {
-  "presets": ["env"]
-}
+  "presets": [["env", { "modules": false }]]
+}

package.json

@@ -3,11 +3,10 @@
   "version": "1.0.3",
   "description": "It is a trap! (for a focus)",
   "main": "dist/index.js",
+  "module": "dist/index.esm.js",
   "unpkg": "umd/index.js",
   "scripts": {
-    "build": "npm run babel && npm run umd",
-    "babel": "babel src -d dist",
-    "umd": "browserify dist/index.js --standalone focusLock -o umd/index.js",
+    "build": "rollup --config rollup.config.js",
     "prepublish": "npm run build",
     "lint": "eslint src tests",
     "lint:fix": "eslint src tests --fix"
@@ -46,9 +45,13 @@
     "babel-preset-es2015": "^6.24.0",
     "babel-preset-stage-2": "^6.22.0",
     "babel-runtime": "^6.23.0",
-    "browserify": "14.4.0",
     "eslint": "^4.6.0",
     "eslint-plugin-vue": "^3.12.0",
+    "rollup": "^1.5.0",
+    "rollup-plugin-babel": "^3.0.7",
+    "rollup-plugin-commonjs": "^9.2.1",
+    "rollup-plugin-node-globals": "^1.4.0",
+    "rollup-plugin-node-resolve": "^4.0.1",
     "style-loader": "^0.15.0"
   },
   "dependencies": {

rollup.config.js

@@ -0,0 +1,45 @@
+'use strict';
+
+const babel = require('rollup-plugin-babel');
+const resolve = require('rollup-plugin-node-resolve');
+const commonjs = require('rollup-plugin-commonjs');
+const globals = require('rollup-plugin-node-globals');
+
+module.exports = [{
+	input: 'src/index.js',
+	output: [
+		{
+			file: 'dist/index.js',
+			format: 'cjs'
+		},
+		{
+			file: 'dist/index.esm.js',
+			format: 'esm'
+		}
+	],
+	plugins: [
+		babel({
+			exclude: 'node_modules/**'
+		})
+	],
+	external: [
+		'focus-lock'
+	]
+}, {
+	input: 'src/index.js',
+	output: [
+		{
+			file: 'umd/index.js',
+			format: 'umd',
+			name: 'focusLock'
+		}
+	],
+	plugins: [
+		babel({
+			exclude: 'node_modules/**'
+		}),
+		resolve(),
+		commonjs(),
+		globals()
+	]
+}];

src/index.js

@@ -1,81 +1,79 @@
-(function () {
-  const {default: moveFocusInside, focusInside, focusIsHidden} = require('focus-lock');
+import moveFocusInside, {focusInside, focusIsHidden} from 'focus-lock';
 
-  let lastActiveTrap = 0;
-  let lastActiveFocus = null;
+let lastActiveTrap = 0;
+let lastActiveFocus = null;
 
 
-  const focusOnBody = () => (
-    document && document.activeElement === document.body
-  );
+const focusOnBody = () => (
+  document && document.activeElement === document.body
+);
 
-  const isFreeFocus = () => focusOnBody() || focusIsHidden();
+const isFreeFocus = () => focusOnBody() || focusIsHidden();
 
 
-  const activateTrap = () => {
-    let result = false;
-    if (lastActiveTrap) {
-      const observed = lastActiveTrap;
-      if(!isFreeFocus()) {
-        if (observed && !focusInside(observed)) {
-          result = moveFocusInside(observed, lastActiveFocus);
-        }
-        lastActiveFocus = document.activeElement;
+const activateTrap = () => {
+  let result = false;
+  if (lastActiveTrap) {
+    const observed = lastActiveTrap;
+    if(!isFreeFocus()) {
+      if (observed && !focusInside(observed)) {
+        result = moveFocusInside(observed, lastActiveFocus);
       }
+      lastActiveFocus = document.activeElement;
     }
-    return result;
-  };
+  }
+  return result;
+};
 
-  const reducePropsToState = (propsList) => {
-    return propsList
-      .filter(node => node)
-      .slice(-1)[0];
-  };
+const reducePropsToState = (propsList) => {
+  return propsList
+    .filter(node => node)
+    .slice(-1)[0];
+};
 
-  const handleStateChangeOnClient = (trap) => {
-    lastActiveTrap = trap;
-    if (trap) {
-      activateTrap();
-    }
-  };
-
-  let instances = [];
+const handleStateChangeOnClient = (trap) => {
+  lastActiveTrap = trap;
+  if (trap) {
+    activateTrap();
+  }
+};
 
-  const emitChange = (event) => {
-    if (handleStateChangeOnClient(reducePropsToState(instances))) {
-      event && event.preventDefault();
-      return true;
-    }
-    return false;
-  };
+let instances = [];
 
-  const attachHandler = () => {
-    document.addEventListener('focusin', emitChange);
-  };
+const emitChange = (event) => {
+  if (handleStateChangeOnClient(reducePropsToState(instances))) {
+    event && event.preventDefault();
+    return true;
+  }
+  return false;
+};
 
-  const detachHandler = () => {
-    document.removeEventListener('focusin', emitChange);
-  };
+const attachHandler = () => {
+  document.addEventListener('focusin', emitChange);
+};
 
-  const focusLock = {
-    on(domNode){
-      if (instances.length === 0) {
-        attachHandler();
-      }
-      if (instances.indexOf(domNode) < 0) {
-        instances.push(domNode);
-        emitChange();
-      }
-    },
+const detachHandler = () => {
+  document.removeEventListener('focusin', emitChange);
+};
 
-    off(domNode){
-      instances = instances.filter(node => node !== domNode);
+const focusLock = {
+  on(domNode){
+    if (instances.length === 0) {
+      attachHandler();
+    }
+    if (instances.indexOf(domNode) < 0) {
+      instances.push(domNode);
       emitChange();
-      if (instances.length === 0) {
-        detachHandler();
-      }
     }
-  };
+  },
+
+  off(domNode){
+    instances = instances.filter(node => node !== domNode);
+    emitChange();
+    if (instances.length === 0) {
+      detachHandler();
+    }
+  }
+};
 
-  module.exports = focusLock;
-})();
+export default focusLock;