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src/node.js

  1. function attrEscape (str) {
  2.   return str.replace(/&/g, '&')
  3.     .replace(/</g, '&lt;')
  4.     .replace(/"/g, '&quot;')
  5.     .replace(/\t/g, '&#x9;')
  6.     .replace(/\n/g, '&#xA;')
  7.     .replace(/\r/g, '&#xD;');
  8. }
  9. function escape (str) {
  10.   return str.replace(/&/g, '&amp;')
  11.     .replace(/</g, '&lt;')
  12.     .replace(/>/g, '&gt;')
  13.     .replace(/\r/g, '&#xD;');
  14. }
  15.  
  16. export const HEAD = Symbol('head');
  17.  
  18. export function props (...keys) {
  19.   return (target) => {
  20.     for (const key of keys) {
  21.       target.elements.push({
  22.         key,
  23.         kind: 'method',
  24.         placement: 'prototype',
  25.         descriptor: {
  26.           get () {
  27.             if (this.attributes) {
  28.               return this.attributes[key];
  29.             }
  30.           },
  31.           set (value) {
  32.             if (this.attributes === undefined) {
  33.               this.attributes = {};
  34.             }
  35.             this.attributes[key] = value;
  36.           },
  37.           configurable: true,
  38.           enumerable: true
  39.         }
  40.       });
  41.     }
  42.     return target;
  43.   };
  44. }
  45.  
  46. export class Node {
  47.   constructor (attributes = {}, children = [], name) {
  48.     for (const key of Object.keys(attributes)) {
  49.       this[key] = attributes[key];
  50.     }
  51.     this.children = children;
  52.     this.__name = name || this.constructor.name.substring(1);
  53.   }
  54.   render () {
  55.     function walk (tree) {
  56.       const name = tree.__name;
  57.       const { attributes, children } = tree;
  58.       const tokens = [];
  59.  
  60.       if (tree[HEAD]) {
  61.         tokens.push(tree[HEAD]);
  62.       }
  63.       tokens.push(`<${name}`);
  64.  
  65.       for (const key of Object.keys(attributes || {})) {
  66.         let v = attributes[key];
  67.         if (v === undefined) continue;
  68.         if (typeof v === 'string') {
  69.           v = attrEscape(v);
  70.         }
  71.         if (typeof v === 'boolean') {
  72.           v = v ? 1 : 0;
  73.         }
  74.         tokens.push(` ${key}="${v}"`);
  75.       }
  76.  
  77.       if (!children.length) {
  78.         tokens.push('/>');
  79.         return tokens;
  80.       }
  81.       tokens.push('>');
  82.       for (const child of children) {
  83.         if (child instanceof Node) {
  84.           tokens.push(child.render());
  85.         } else if (typeof child === 'string') {
  86.           tokens.push(escape(child));
  87.         } else {
  88.           tokens.push(child.toString());
  89.         }
  90.       }
  91.       tokens.push(`</${name}>`);
  92.       return tokens;
  93.     }
  94.     return walk(this).join('');
  95.   }
  96. }