Lady’s Gitweb - Lemon/blob - window/mod.js

   1 // 🍋🏷 Lemon ∷ window/mod.js
   2 // ====================================================================
   3 //
   4 // Copyright © 2022 Lady [@ Lady’s Computer].
   5 //
   6 // This Source Code Form is subject to the terms of the Mozilla Public
   7 // License, v. 2.0. If a copy of the MPL was not distributed with this
   8 // file, You can obtain one at <https://mozilla.org/MPL/2.0/>.
   9
  10 import {
  11   DOMImplementation,
  12   DOMParser,
  13   xhtmlNamespace,
  14   XMLSerializer,
  15 } from "./deps.js";
  16
  17 { // Polyfill global interfaces.
  18   Object.assign(globalThis, {
  19     DOMImplementation,
  20     DOMParser,
  21     XMLSerializer,
  22   });
  23 }
  24
  25 { // Polyfill document.
  26   globalThis.document = new DOMImplementation().createDocument(
  27     xhtmlNamespace,
  28     "html",
  29     null,
  30   );
  31   const { documentElement } = document;
  32   documentElement.appendChild(
  33     document.createElementNS(xhtmlNamespace, "head"),
  34   );
  35   documentElement.appendChild(
  36     document.createElementNS(xhtmlNamespace, "body"),
  37   );
  38 }
  39
  40 { // Polyfill Element::append.
  41   Object.getPrototypeOf(
  42     globalThis.document.documentElement,
  43   ).append = function (...children) {
  44     for (const child of children) {
  45       this.appendChild(
  46         typeof child === "string"
  47           ? this.ownerDocument.createTextNode(child)
  48           : child,
  49       );
  50     }
  51   };
  52 }
  53
  54 { // Apply patches to Node::nodeType and Node::normalize.
  55   const nodePrototype = Object.getPrototypeOf(
  56     Object.getPrototypeOf(document.createDocumentFragment()),
  57   );
  58   const originalNodeTypeGetter = Object.getOwnPropertyDescriptor(
  59     nodePrototype,
  60     "nodeType",
  61   )?.get ?? (() => {
  62     const { nodeType: originalNodeTypeValue } = nodePrototype;
  63     return () => originalNodeTypeValue;
  64   })();
  65   Object.defineProperty(nodePrototype, "nodeType", {
  66     configurable: true,
  67     enumerable: true,
  68     /**
  69      * To simulate restrictions on calling `nodeType` only on actual
  70      * Nodes, check for inheritance first.
  71      */
  72     get() {
  73       if (
  74         !(() => {
  75           // Test whether this object has the node prototype in its
  76           // prototype chain.
  77           for (
  78             let prototype = this === Object(this)
  79               ? Object.getPrototypeOf(this)
  80               : null;
  81             prototype != null;
  82             prototype = Object.getPrototypeOf(prototype)
  83           ) {
  84             if (prototype === nodePrototype) {
  85               // This object inherits from the Node prototype.
  86               return true;
  87             } else {
  88               // This object is not yet known to inherits from the Node
  89               // prototype.
  90               continue;
  91             }
  92           }
  93         })()
  94       ) {
  95         // This is not a Node.
  96         throw new TypeError("nodeType requires this be a Node.");
  97       } else {
  98         // This is a Node; walk the prototype chain and attempt to get
  99         // the node type.
 100         for (
 101           //deno-lint-ignore no-this-alias
 102           let target = this;
 103           target != null && target != nodePrototype;
 104           target = Object.getPrototypeOf(target)
 105         ) {
 106           if (Object.hasOwn(target, "nodeType")) {
 107             return Reflect.get(target, "nodeType", this);
 108           } else {
 109             continue;
 110           }
 111         }
 112         return originalNodeTypeGetter.call(this);
 113       }
 114     },
 115     set: undefined,
 116   });
 117   nodePrototype.normalize = function () {
 118     let child = this.firstChild;
 119     while (child) {
 120       const next = child.nextSibling;
 121       if (next && next.nodeType == 3 && child.nodeType == 3) {
 122         this.removeChild(next);
 123         child.appendData(next.data);
 124       } else {
 125         if (child.nodeType == 3 && !child.data) {
 126           this.removeChild(child);
 127         } else {
 128           child.normalize();
 129         }
 130         child = next;
 131       }
 132     }
 133   };
 134 }