refractor/lang/javascript.js

Lightweight, robust, elegant virtual syntax highlighting using Prism

'use strict';

module.exports = javascript;
javascript.displayName = 'javascript';
javascript.aliases = ['js'];
function javascript(Prism) {
  Prism.languages.javascript = Prism.languages.extend('clike', {
    keyword: /\b(?:as|async|await|break|case|catch|class|const|continue|debugger|default|delete|do|else|enum|export|extends|finally|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/,
    number: /\b-?(?:0[xX][\dA-Fa-f]+|0[bB][01]+|0[oO][0-7]+|\d*\.?\d+(?:[Ee][+-]?\d+)?|NaN|Infinity)\b/,
    // Allow for all non-ASCII characters (See http://stackoverflow.com/a/2008444)
    function: /[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?=\s*\()/i,
    operator: /-[-=]?|\+[+=]?|!=?=?|<<?=?|>>?>?=?|=(?:==?|>)?|&[&=]?|\|[|=]?|\*\*?=?|\/=?|~|\^=?|%=?|\?|\.{3}/
  });
  Prism.languages.insertBefore('javascript', 'keyword', {
    regex: {
      pattern: /(^|[^/])\/(?!\/)(\[[^\]\r\n]+]|\\.|[^/\\\[\r\n])+\/[gimyu]{0,5}(?=\s*($|[\r\n,.;})]))/,
      lookbehind: true,
      greedy: true
    },
    // This must be declared before keyword because we use "function" inside the look-forward
    'function-variable': {
      pattern: /[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?=\s*=\s*(?:function\b|(?:\([^()]*\)|[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*)\s*=>))/i,
      alias: 'function'
    }
  });
  Prism.languages.insertBefore('javascript', 'string', {
    'template-string': {
      pattern: /`(?:\\[\s\S]|[^\\`])*`/,
      greedy: true,
      inside: {
        interpolation: {
          pattern: /\$\{[^}]+\}/,
          inside: {
            'interpolation-punctuation': {
              pattern: /^\$\{|\}$/,
              alias: 'punctuation'
            },
            rest: Prism.languages.javascript
          }
        },
        string: /[\s\S]+/
      }
    }
  });
  if (Prism.languages.markup) {
    Prism.languages.insertBefore('markup', 'tag', {
      script: {
        pattern: /(<script[\s\S]*?>)[\s\S]*?(?=<\/script>)/i,
        lookbehind: true,
        inside: Prism.languages.javascript,
        alias: 'language-javascript',
        greedy: true
      }
    });
  }
  Prism.languages.js = Prism.languages.javascript;
}