remove some polyfills (#1288)

* remove some polyfills

* use for-of for iteration when possible

packages/slate-html-serializer/src/index.js

@@ -256,8 +256,7 @@ class Html {
       }
     }
 
-    for (let i = 0; i < this.rules.length; i++) {
+    for (const rule of this.rules) {
-      const rule = this.rules[i]
       if (!rule.deserialize) continue
       const ret = rule.deserialize(element, next)
       const type = typeOf(ret)
@@ -354,8 +353,7 @@ class Html {
 
     const children = node.nodes.map(this.serializeNode)
 
-    for (let i = 0; i < this.rules.length; i++) {
+    for (const rule of this.rules) {
-      const rule = this.rules[i]
       if (!rule.serialize) continue
       const ret = rule.serialize(node, children)
       if (ret) return addKey(ret)
@@ -376,8 +374,7 @@ class Html {
     const text = this.serializeString(string)
 
     return leaf.marks.reduce((children, mark) => {
-      for (let i = 0; i < this.rules.length; i++) {
+      for (const rule of this.rules) {
-        const rule = this.rules[i]
         if (!rule.serialize) continue
         const ret = rule.serialize(mark, children)
         if (ret) return addKey(ret)
@@ -395,8 +392,7 @@ class Html {
    */
 
   serializeString = (string) => {
-    for (let i = 0; i < this.rules.length; i++) {
+    for (const rule of this.rules) {
-      const rule = this.rules[i]
       if (!rule.serialize) continue
       const ret = rule.serialize(string, string.text)
       if (ret) return ret

packages/slate-react/src/components/content.js

@@ -8,7 +8,6 @@ import logger from 'slate-dev-logger'
 
 import EVENT_HANDLERS from '../constants/event-handlers'
 import Node from './node'
-import findClosestNode from '../utils/find-closest-node'
 import findDOMRange from '../utils/find-dom-range'
 import findRange from '../utils/find-range'
 import scrollToSelection from '../utils/scroll-to-selection'
@@ -210,7 +209,7 @@ class Content extends React.Component {
     const el = target.nodeType === 3 ? target.parentNode : target
     return (
       (el.isContentEditable) &&
-      (el === element || findClosestNode(el, '[data-slate-editor]') === element)
+      (el === element || el.closest('[data-slate-editor]') === element)
     )
   }
 
@@ -269,7 +268,7 @@ class Content extends React.Component {
       handler == 'onDragStart'
     ) {
       const { target } = event
-      const targetEditorNode = findClosestNode(target, '[data-slate-editor]')
+      const targetEditorNode = target.closest('[data-slate-editor]')
       if (targetEditorNode !== this.element) return
     }
 

packages/slate-react/src/components/editor.js

@@ -140,8 +140,7 @@ class Editor extends React.Component {
     let isNew = false
 
     // Check to see if any plugin-related properœties have changed.
-    for (let i = 0; i < PLUGINS_PROPS.length; i++) {
+    for (const prop of PLUGINS_PROPS) {
-      const prop = PLUGINS_PROPS[i]
       if (props[prop] == this.props[prop]) continue
       isNew = true
       break
@@ -377,9 +376,8 @@ function resolvePlugins(props) {
  * Mix in the property types for the event handlers.
  */
 
-for (let i = 0; i < EVENT_HANDLERS.length; i++) {
+for (const prop of EVENT_HANDLERS) {
-  const property = EVENT_HANDLERS[i]
+  Editor.propTypes[prop] = Types.func
-  Editor.propTypes[property] = Types.func
 }
 
 /**

packages/slate-react/src/constants/environment.js

@@ -59,16 +59,14 @@ let OS
 if (browser) {
   const { userAgent } = window.navigator
 
-  for (let i = 0; i < BROWSER_RULES.length; i++) {
+  for (const [ name, regexp ] of BROWSER_RULES) {
-    const [ name, regexp ] = BROWSER_RULES[i]
     if (regexp.test(userAgent)) {
       BROWSER = name
       break
     }
   }
 
-  for (let i = 0; i < OS_RULES.length; i++) {
+  for (const [ name, regexp ] of OS_RULES) {
-    const [ name, regexp ] = OS_RULES[i]
     if (regexp.test(userAgent)) {
       OS = name
       break
@@ -78,8 +76,7 @@ if (browser) {
   const testEl = window.document.createElement('div')
   testEl.contentEditable = true
 
-  for (let i = 0; i < EVENT_RULES.length; i++) {
+  for (const [ name, testFn ] of EVENT_RULES) {
-    const [ name, testFn ] = EVENT_RULES[i]
     EVENTS[name] = testFn(testEl)
   }
 }

packages/slate-react/src/utils/find-closest-node.js

@@ -1,37 +0,0 @@
-
-/**
- * Find the closest ancestor of a DOM `element` that matches a given selector.
- *
- * COMPAT: In IE11, the `Node.closest` method doesn't exist natively, so we
- * have to polyfill it. (2017/09/06)
- *
- * https://developer.mozilla.org/en-US/docs/Web/API/Element/closest#Polyfill
- *
- * @param {Element} node
- * @param {String} selector
- * @return {Element}
- */
-
-function findClosestNode(node, selector) {
-  if (typeof node.closest === 'function') return node.closest(selector)
-
-  const matches = (node.document || node.ownerDocument).querySelectorAll(selector)
-  let parentNode = node
-  let i
-
-  do {
-    i = matches.length
-    while (--i >= 0 && matches.item(i) !== parentNode);
-  }
-  while ((i < 0) && (parentNode = parentNode.parentElement))
-
-  return parentNode
-}
-
-/**
- * Export.
- *
- * @type {Function}
- */
-
-export default findClosestNode

packages/slate-react/src/utils/find-node.js

@@ -1,6 +1,4 @@
 
-import findClosestNode from './find-closest-node'
-
 /**
  * Find a Slate node from a DOM `element`.
  *
@@ -9,7 +7,7 @@ import findClosestNode from './find-closest-node'
  */
 
 function findNode(element, state) {
-  const closest = findClosestNode(element, '[data-key]')
+  const closest = element.closest('[data-key]')
   if (!closest) return null
 
   const key = closest.getAttribute('data-key')

packages/slate-react/src/utils/find-point.js

@@ -2,7 +2,6 @@
 import getWindow from 'get-window'
 
 import OffsetKey from './offset-key'
-import findClosestNode from './find-closest-node'
 
 /**
  * Constants.
@@ -32,7 +31,7 @@ function findPoint(nativeNode, nativeOffset, state) {
 
   const window = getWindow(nativeNode)
   const { parentNode } = nearestNode
-  let rangeNode = findClosestNode(parentNode, RANGE_SELECTOR)
+  let rangeNode = parentNode.closest(RANGE_SELECTOR)
   let offset
   let node
 
@@ -40,7 +39,7 @@ function findPoint(nativeNode, nativeOffset, state) {
   // determine what the offset relative to the text node is.
   if (rangeNode) {
     const range = window.document.createRange()
-    const textNode = findClosestNode(rangeNode, TEXT_SELECTOR)
+    const textNode = rangeNode.closest(TEXT_SELECTOR)
     range.setStart(textNode, 0)
     range.setEnd(nearestNode, nearestOffset)
     node = textNode
@@ -50,7 +49,7 @@ function findPoint(nativeNode, nativeOffset, state) {
   // For void nodes, the element with the offset key will be a cousin, not an
   // ancestor, so find it by going down from the nearest void parent.
   else {
-    const voidNode = findClosestNode(parentNode, VOID_SELECTOR)
+    const voidNode = parentNode.closest(VOID_SELECTOR)
     if (!voidNode) return null
     rangeNode = voidNode.querySelector(RANGE_SELECTOR)
     node = rangeNode

packages/slate/package.json

@@ -8,7 +8,6 @@
   "dependencies": {
     "debug": "^2.3.2",
     "direction": "^0.1.5",
-    "es6-map": "^0.1.4",
     "esrever": "^0.2.0",
     "is-empty": "^1.0.0",
     "is-plain-object": "^2.0.4",

packages/slate/src/models/node.js

@@ -649,8 +649,7 @@ class Node {
   getDescendantAtPath(path) {
     let descendant = this
 
-    for (let i = 0; i < path.length; i++) {
+    for (const index of path) {
-      const index = path[i]
       if (!descendant) return
       if (!descendant.nodes) return
       descendant = descendant.nodes.get(index)

packages/slate/src/models/stack.js

@@ -76,8 +76,7 @@ class Stack extends Record(DEFAULTS) {
   find(property, ...args) {
     const plugins = this.getPluginsWith(property)
 
-    for (let i = 0; i < plugins.length; i++) {
+    for (const plugin of plugins) {
-      const plugin = plugins[i]
       const ret = plugin[property](...args)
       if (ret != null) return ret
     }
@@ -95,8 +94,7 @@ class Stack extends Record(DEFAULTS) {
     const plugins = this.getPluginsWith(property)
     const array = []
 
-    for (let i = 0; i < plugins.length; i++) {
+    for (const plugin of plugins) {
-      const plugin = plugins[i]
       const value = plugin[property](...args)
       if (value != null) array.push(value)
     }
@@ -114,8 +112,7 @@ class Stack extends Record(DEFAULTS) {
   run(property, ...args) {
     const plugins = this.getPluginsWith(property)
 
-    for (let i = 0; i < plugins.length; i++) {
+    for (const plugin of plugins) {
-      const plugin = plugins[i]
       const ret = plugin[property](...args)
       if (ret != null) return
     }
@@ -133,8 +130,7 @@ class Stack extends Record(DEFAULTS) {
     const plugins = this.getPluginsWith(property).reverse()
     let { children = null } = props
 
-    for (let i = 0; i < plugins.length; i++) {
+    for (const plugin of plugins) {
-      const plugin = plugins[i]
       const value = plugin[property](props, ...args)
       if (value == null) continue
       props.children = children = value

packages/slate/src/utils/memoize.js

@@ -1,6 +1,4 @@
 
-import Map from 'es6-map'
-
 /**
  * Is in development?
  *
@@ -67,8 +65,7 @@ const UNSET = undefined
 function memoize(object, properties, options = {}) {
   const { takesArguments = true } = options
 
-  for (let i = 0; i < properties.length; i++) {
+  for (const property of properties) {
-    const property = properties[i]
     const original = object[property]
 
     if (!original) {
@@ -83,12 +80,12 @@ function memoize(object, properties, options = {}) {
         // If the cache key is different, previous caches must be cleared.
         if (CACHE_KEY !== this.__cache_key) {
           this.__cache_key = CACHE_KEY
-          this.__cache = new Map()
+          this.__cache = new Map() // eslint-disable-line no-undef,no-restricted-globals
         }
       }
 
       if (!this.__cache) {
-        this.__cache = new Map()
+        this.__cache = new Map() // eslint-disable-line no-undef,no-restricted-globals
       }
 
       let cachedValue
@@ -133,8 +130,7 @@ function memoize(object, properties, options = {}) {
  */
 
 function getIn(map, keys) {
-  for (let i = 0; i < keys.length; i++) {
+  for (const key of keys) {
-    const key = keys[i]
     map = map.get(key)
     if (map === UNSET) return UNSET
   }
@@ -155,13 +151,12 @@ function setIn(map, keys, value) {
   let parent = map
   let child
 
-  for (let i = 0; i < keys.length; i++) {
+  for (const key of keys) {
-    const key = keys[i]
     child = parent.get(key)
 
     // If the path was not created yet...
     if (child === UNSET) {
-      child = new Map()
+      child = new Map() // eslint-disable-line no-undef,no-restricted-globals
       parent.set(key, child)
     }
 

yarn.lock

@@ -2198,7 +2198,7 @@ es6-iterator@2, es6-iterator@^2.0.1, es6-iterator@~2.0.1:
     es5-ext "^0.10.14"
     es6-symbol "^3.1"
 
-es6-map@^0.1.3, es6-map@^0.1.4:
+es6-map@^0.1.3:
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/es6-map/-/es6-map-0.1.5.tgz#9136e0503dcc06a301690f0bb14ff4e364e949f0"
   dependencies: