perf(@vant/lazyload): reuse some utils (#9591)

packages/vant-lazyload/package.json

@@ -25,6 +25,9 @@
     "@babel/core": "^7.12.9",
     "release-it": "^14.2.2"
   },
+  "dependencies": {
+    "@vant/use": "^1.3.1"
+  },
   "release-it": {
     "git": {
       "tag": false,

packages/vant-lazyload/src/lazy-component.js

@@ -1,5 +1,5 @@
 import { h } from 'vue';
-import { inBrowser } from './util';
+import { inBrowser } from '@vant/use';
 
 export default (lazy) => ({
   props: {

packages/vant-lazyload/src/lazy-container.js

@@ -1,5 +1,6 @@
 /* eslint-disable max-classes-per-file */
-import { find, remove } from './util';
+/* eslint-disable prefer-object-spread */
+import { remove } from './util';
 
 const defaultOptions = {
   selector: 'img',
@@ -74,13 +75,13 @@ export default class LazyContainerManager {
   }
 
   update(el, binding, vnode) {
-    const container = find(this._queue, (item) => item.el === el);
+    const container = this._queue.find((item) => item.el === el);
     if (!container) return;
     container.update({ el, binding, vnode });
   }
 
   unbind(el) {
-    const container = find(this._queue, (item) => item.el === el);
+    const container = this._queue.find((item) => item.el === el);
     if (!container) return;
     container.clear();
     remove(this._queue, container);

packages/vant-lazyload/src/lazy-image.js

@@ -1,4 +1,5 @@
-import { inBrowser, loadImageAsync, noop } from './util';
+import { inBrowser } from '@vant/use';
+import { loadImageAsync, noop } from './util';
 
 export default (lazyManager) => ({
   props: {

packages/vant-lazyload/src/lazy.js

@@ -1,13 +1,12 @@
 import { nextTick } from 'vue';
+import { inBrowser, getScrollParent } from '@vant/use';
 import {
-  inBrowser,
   remove,
-  find,
+  on,
-  _,
+  off,
   throttle,
   supportWebp,
   getDPR,
-  scrollParent,
   getBestSelectionFromSrcset,
   isObject,
   hasIntersectionObserver,
@@ -147,7 +146,7 @@ export default function () {
         }
 
         if (!$parent) {
-          $parent = scrollParent(el);
+          $parent = getScrollParent(el);
         }
 
         const newListener = new ReactiveListener({
@@ -186,7 +185,7 @@ export default function () {
       let { src } = value;
       src = getBestSelectionFromSrcset(el, this.options.scale) || src;
 
-      const exist = find(this.ListenerQueue, (item) => item.el === el);
+      const exist = this.ListenerQueue.find((item) => item.el === el);
       if (!exist) {
         this.add(el, binding, vnode);
       } else {
@@ -212,7 +211,7 @@ export default function () {
     remove(el) {
       if (!el) return;
       this._observer && this._observer.unobserve(el);
-      const existItem = find(this.ListenerQueue, (item) => item.el === el);
+      const existItem = this.ListenerQueue.find((item) => item.el === el);
       if (existItem) {
         this._removeListenerTarget(existItem.$parent);
         this._removeListenerTarget(window);
@@ -273,7 +272,7 @@ export default function () {
      */
     _addListenerTarget(el) {
       if (!el) return;
-      let target = find(this.TargetQueue, (target) => target.el === el);
+      let target = this.TargetQueue.find((target) => target.el === el);
       if (!target) {
         target = {
           el,
@@ -315,7 +314,7 @@ export default function () {
      */
     _initListen(el, start) {
       this.options.ListenEvents.forEach((evt) =>
-        _[start ? 'on' : 'off'](el, evt, this.lazyLoadHandler)
+        (start ? on : off)(el, evt, this.lazyLoadHandler)
       );
     }
 

packages/vant-lazyload/src/listener.js

@@ -32,7 +32,6 @@ export default class ReactiveListener {
     this.elRenderer = elRenderer;
     this._imageCache = imageCache;
     this.performanceData = {
-      init: Date.now(),
       loadStart: 0,
       loadEnd: 0,
     };

packages/vant-lazyload/src/util.js

@@ -1,4 +1,4 @@
-const inBrowser = typeof window !== 'undefined';
+import { inBrowser } from '@vant/use';
 
 export const hasIntersectionObserver =
   inBrowser &&
@@ -11,13 +11,13 @@ export const modeType = {
   observer: 'observer',
 };
 
-function remove(arr, item) {
+export function remove(arr, item) {
   if (!arr.length) return;
   const index = arr.indexOf(item);
   if (index > -1) return arr.splice(index, 1);
 }
 
-function getBestSelectionFromSrcset(el, scale) {
+export function getBestSelectionFromSrcset(el, scale) {
   if (el.tagName !== 'IMG' || !el.getAttribute('data-srcset')) return;
 
   let options = el.getAttribute('data-srcset');
@@ -82,21 +82,10 @@ function getBestSelectionFromSrcset(el, scale) {
   return bestSelectedSrc;
 }
 
-function find(arr, fn) {
+export const getDPR = (scale = 1) =>
-  let item;
-  for (let i = 0, len = arr.length; i < len; i++) {
-    if (fn(arr[i])) {
-      item = arr[i];
-      break;
-    }
-  }
-  return item;
-}
-
-const getDPR = (scale = 1) =>
   inBrowser ? window.devicePixelRatio || scale : scale;
 
-function supportWebp() {
+export function supportWebp() {
   if (!inBrowser) return false;
 
   let support = true;
@@ -114,7 +103,7 @@ function supportWebp() {
   return support;
 }
 
-function throttle(action, delay) {
+export function throttle(action, delay) {
   let timeout = null;
   let lastRun = 0;
   return function (...args) {
@@ -135,19 +124,18 @@ function throttle(action, delay) {
   };
 }
 
-const _ = {
+export function on(el, type, func) {
-  on(el, type, func, capture = false) {
   el.addEventListener(type, func, {
-      capture,
+    capture: false,
     passive: true,
   });
-  },
+}
-  off(el, type, func, capture = false) {
-    el.removeEventListener(type, func, capture);
-  },
-};
 
-const loadImageAsync = (item, resolve, reject) => {
+export function off(el, type, func) {
+  el.removeEventListener(type, func, false);
+}
+
+export const loadImageAsync = (item, resolve, reject) => {
   const image = new Image();
 
   if (!item || !item.src) {
@@ -160,61 +148,23 @@ const loadImageAsync = (item, resolve, reject) => {
     image.crossOrigin = item.cors;
   }
 
-  image.onload = function () {
+  image.onload = () =>
     resolve({
       naturalHeight: image.naturalHeight,
       naturalWidth: image.naturalWidth,
       src: image.src,
     });
+
+  image.onerror = (e) => reject(e);
 };
 
-  image.onerror = function (e) {
+export function isObject(obj) {
-    reject(e);
-  };
-};
-
-const style = (el, prop) =>
-  typeof getComputedStyle !== 'undefined'
-    ? getComputedStyle(el, null).getPropertyValue(prop)
-    : el.style[prop];
-
-const overflow = (el) =>
-  style(el, 'overflow') + style(el, 'overflow-y') + style(el, 'overflow-x');
-
-const scrollParent = (el) => {
-  if (!inBrowser) return;
-  if (!(el instanceof HTMLElement)) {
-    return window;
-  }
-
-  let parent = el;
-
-  while (parent) {
-    if (parent === document.body || parent === document.documentElement) {
-      break;
-    }
-
-    if (!parent.parentNode) {
-      break;
-    }
-
-    if (/(scroll|auto)/.test(overflow(parent))) {
-      return parent;
-    }
-
-    parent = parent.parentNode;
-  }
-
-  return window;
-};
-
-function isObject(obj) {
   return obj !== null && typeof obj === 'object';
 }
 
-function noop() {}
+export function noop() {}
 
-class ImageCache {
+export class ImageCache {
   constructor({ max }) {
     this.options = {
       max: max || 100,
@@ -238,19 +188,3 @@ class ImageCache {
     this._caches.shift();
   }
 }
-
-export {
-  ImageCache,
-  inBrowser,
-  remove,
-  find,
-  noop,
-  _,
-  isObject,
-  throttle,
-  supportWebp,
-  getDPR,
-  scrollParent,
-  loadImageAsync,
-  getBestSelectionFromSrcset,
-};

packages/vant-lazyload/yarn.lock

@@ -397,6 +397,11 @@
   dependencies:
     "@types/node" "*"
 
+"@vant/use@^1.3.1":
+  version "1.3.1"
+  resolved "https://registry.nlark.com/@vant/use/download/@vant/use-1.3.1.tgz?cache=0&sync_timestamp=1632302722581&other_urls=https%3A%2F%2Fregistry.nlark.com%2F%40vant%2Fuse%2Fdownload%2F%40vant%2Fuse-1.3.1.tgz#8609fc7f86713df0c4ace7109eee6df2f3bd9a0f"
+  integrity sha1-hgn8f4ZxPfDErOcQnu5t8vO9mg8=
+
 ansi-align@^3.0.0:
   version "3.0.0"
   resolved "https://registry.npm.taobao.org/ansi-align/download/ansi-align-3.0.0.tgz#b536b371cf687caaef236c18d3e21fe3797467cb"