marked.js

/**
 * marked - A markdown parser (https://github.com/chjj/marked)
 * Copyright (c) 2011-2012, Christopher Jeffrey. (MIT Licensed)
 */

;(function() {

/**
 * Block-Level Grammar
 */

var block = {
  newline: /^\n+/,
  code: /^ {4,}[^\n]*(?:\n {4,}[^\n]*|\n)*(?:\n+|$)/,
  gfm_code: /^ *``` *(\w+)? *\n([^\0]+?)\s*``` *(?:\n+|$)/,
  hr: /^( *[\-*_]){3,} *(?:\n+|$)/,
  heading: /^ *(#{1,6}) *([^\n]+?) *#* *(?:\n+|$)/,
  lheading: /^([^\n]+)\n *(=|-){3,} *\n*/,
  blockquote: /^( *>[^\n]+(\n[^\n]+)*\n*)+/,
  list: /^( *)([*+-]|\d+\.) [^\0]+?(?:\n{2,}(?! )|\s*$)(?!\1bullet)\n*/,
  html: /^ *(?:comment|closed|closing) *(?:\n{2,}|\s*$)/,
  def: /^ *\[([^\]]+)\]: *([^\s]+)(?: +["(]([^\n]+)[")])? *(?:\n+|$)/,
  paragraph: /^([^\n]+\n?(?!body))+\n*/,
  text: /^[^\n]+/
};

block.list = (function() {
  var list = block.list.source;

  list = list
    .replace('bullet', /(?:[*+-](?!(?: *[-*]){2,})|\d+\.)/.source);

  return new RegExp(list);
})();

block.html = (function() {
  var html = block.html.source;

  html = html
    .replace('comment', /<!--[^\0]*?-->/.source)
    .replace('closed', /<(tag)[^\0]+?<\/\1>/.source)
    .replace('closing', /<tag(?!:\/|@)\b(?:"[^"]*"|'[^']*'|[^'">])*?>/.source)
    .replace(/tag/g, tag());

  return new RegExp(html);
})();

block.paragraph = (function() {
  var paragraph = block.paragraph.source
    , body = [];

  (function push(rule) {
    rule = block[rule] ? block[rule].source : rule;
    body.push(rule.replace(/(^|[^\[])\^/g, '$1'));
    return push;
  })
  ('gfm_code')
  ('hr')
  ('heading')
  ('lheading')
  ('blockquote')
  ('<' + tag())
  ('def');

  return new
    RegExp(paragraph.replace('body', body.join('|')));
})();

/**
 * Block Lexer
 */

block.lexer = function(src) {
  var tokens = [];

  tokens.links = {};

  src = src
    .replace(/\r\n|\r/g, '\n')
    .replace(/\t/g, '    ');

  return block.token(src, tokens, true);
};

block.token = function(src, tokens, top) {
  var src = src.replace(/^ +$/gm, '')
    , next
    , loose
    , cap
    , item
    , space
    , i
    , l;

  while (src) {
    // newline
    if (cap = block.newline.exec(src)) {
      src = src.substring(cap[0].length);
      if (cap[0].length > 1) {
        tokens.push({
          type: 'space'
        });
      }
    }

    // code
    if (cap = block.code.exec(src)) {
      src = src.substring(cap[0].length);
      cap = cap[0].replace(/^ {4}/gm, '');
      tokens.push({
        type: 'code',
        text: cap.replace(/\n+$/, '')
      });
      continue;
    }

    // gfm_code
    if (cap = block.gfm_code.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'code',
        lang: cap[1],
        text: cap[2]
      });
      continue;
    }

    // heading
    if (cap = block.heading.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'heading',
        depth: cap[1].length,
        text: cap[2]
      });
      continue;
    }

    // lheading
    if (cap = block.lheading.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'heading',
        depth: cap[2] === '=' ? 1 : 2,
        text: cap[1]
      });
      continue;
    }

    // hr
    if (cap = block.hr.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'hr'
      });
      continue;
    }

    // blockquote
    if (cap = block.blockquote.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'blockquote_start'
      });

      cap = cap[0].replace(/^ *> ?/gm, '');

      // Pass `top` to keep the current
      // "toplevel" state. This is exactly
      // how markdown.pl works.
      block.token(cap, tokens, top);

      tokens.push({
        type: 'blockquote_end'
      });
      continue;
    }

    // list
    if (cap = block.list.exec(src)) {
      src = src.substring(cap[0].length);

      tokens.push({
        type: 'list_start',
        ordered: isFinite(cap[2])
      });

      // Get each top-level item.
      cap = cap[0].match(
        /^( *)([*+-]|\d+\.)[^\n]*(?:\n(?!\1(?:[*+-]|\d+\.))[^\n]*)*/gm
      );

      next = false;
      l = cap.length;
      i = 0;

      for (; i < l; i++) {
        item = cap[i];

        // Remove the list item's bullet
        // so it is seen as the next token.
        space = item.length;
        item = item.replace(/^ *([*+-]|\d+\.) */, '');

        // Outdent whatever the
        // list item contains. Hacky.
        if (~item.indexOf('\n ')) {
          space -= item.length;
          item = item.replace(new RegExp('^ {1,' + space + '}', 'gm'), '');
        }

        // Determine whether item is loose or not.
        // Use: /(^|\n)(?! )[^\n]+\n\n(?!\s*$)/
        // for discount behavior.
        loose = next || /\n\n(?!\s*$)/.test(item);
        if (i !== l - 1) {
          next = item[item.length-1] === '\n';
          if (!loose) loose = next;
        }

        tokens.push({
          type: loose
            ? 'loose_item_start'
            : 'list_item_start'
        });

        // Recurse.
        block.token(item, tokens);

        tokens.push({
          type: 'list_item_end'
        });
      }

      tokens.push({
        type: 'list_end'
      });

      continue;
    }

    // html
    if (cap = block.html.exec(src)) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'html',
        text: cap[0]
      });
      continue;
    }

    // def
    if (top && (cap = block.def.exec(src))) {
      src = src.substring(cap[0].length);
      tokens.links[cap[1].toLowerCase()] = {
        href: cap[2],
        title: cap[3]
      };
      continue;
    }

    // top-level paragraph
    if (top && (cap = block.paragraph.exec(src))) {
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'paragraph',
        text: cap[0]
      });
      continue;
    }

    // text
    if (cap = block.text.exec(src)) {
      // Top-level should never reach here.
      src = src.substring(cap[0].length);
      tokens.push({
        type: 'text',
        text: cap[0]
      });
      continue;
    }
  }

  return tokens;
};

/**
 * Inline Processing
 */

var inline = {
  escape: /^\\([\\`*{}\[\]()#+\-.!_>])/,
  autolink: /^<([^ >]+(@|:\/)[^ >]+)>/,
  gfm_autolink: /^(\w+:\/\/[^\s]+[^.,:;"')\]\s])/,
  tag: /^<!--[^\0]*?-->|^<\/?\w+(?:"[^"]*"|'[^']*'|[^'">])*?>/,
  link: /^!?\[((?:\[[^\]]*\]|[^\[\]]|\[|\](?=[^[\]]*\]))*)\]\(([^\)]*)\)/,
  reflink: /^!?\[((?:\[[^\]]*\]|[^\[\]]|\[|\](?=[^[\]]*\]))*)\]\s*\[([^\]]*)\]/,
  nolink: /^!?\[((?:\[[^\]]*\]|[^\[\]])*)\]/,
  strong: /^__([^\0]+?)__(?!_)|^\*\*([^\0]+?)\*\*(?!\*)/,
  em: /^\b_([^\0]+?)_\b|^\*((?:\*\*|[^\0])+?)\*(?!\*)/,
  code: /^(`+)([^\0]*?[^`])\1(?!`)/,
  br: /^ {2,}\n(?!\s*$)/,
  text: /^[^\0]+?(?=[\\<!\[_*`]|\w+:\/\/| {2,}\n|$)/
};

/**
 * Inline Lexer
 */

inline.lexer = function(src) {
  var out = ''
    , links = tokens.links
    , link
    , text
    , href
    , cap;

  while (src) {
    // escape
    if (cap = inline.escape.exec(src)) {
      src = src.substring(cap[0].length);
      out += cap[1];
      continue;
    }

    // autolink
    if (cap = inline.autolink.exec(src)) {
      src = src.substring(cap[0].length);
      if (cap[2] === '@') {
        text = cap[1][6] === ':'
          ? mangle(cap[1].substring(7))
          : mangle(cap[1]);
        href = mangle('mailto:') + text;
      } else {
        text = escape(cap[1]);
        href = text;
      }
      out += '<a href="'
        + href
        + '">'
        + text
        + '</a>';
      continue;
    }

    // gfm_autolink
    if (cap = inline.gfm_autolink.exec(src)) {
      src = src.substring(cap[0].length);
      text = escape(cap[1]);
      href = text;
      out += '<a href="'
        + href
        + '">'
        + text
        + '</a>';
      continue;
    }

    // tag
    if (cap = inline.tag.exec(src)) {
      src = src.substring(cap[0].length);
      out += cap[0];
      continue;
    }

    // link
    if (cap = inline.link.exec(src)) {
      src = src.substring(cap[0].length);
      text = /^\s*<?([^\s]*?)>?(?:\s+"([^\n]+)")?\s*$/.exec(cap[2]);
      if (!text) {
        out += cap[0][0];
        src = cap[0].substring(1) + src;
        continue;
      }
      out += outputLink(cap, {
        href: text[1],
        title: text[2]
      });
      continue;
    }

    // reflink, nolink
    if ((cap = inline.reflink.exec(src))
        || (cap = inline.nolink.exec(src))) {
      src = src.substring(cap[0].length);
      link = (cap[2] || cap[1]).replace(/\s+/g, ' ');
      link = links[link.toLowerCase()];
      if (!link || !link.href) {
        out += cap[0][0];
        src = cap[0].substring(1) + src;
        continue;
      }
      out += outputLink(cap, link);
      continue;
    }

    // strong
    if (cap = inline.strong.exec(src)) {
      src = src.substring(cap[0].length);
      out += '<strong>'
        + inline.lexer(cap[2] || cap[1])
        + '</strong>';
      continue;
    }

    // em
    if (cap = inline.em.exec(src)) {
      src = src.substring(cap[0].length);
      out += '<em>'
        + inline.lexer(cap[2] || cap[1])
        + '</em>';
      continue;
    }

    // code
    if (cap = inline.code.exec(src)) {
      src = src.substring(cap[0].length);
      out += '<code>'
        + escape(cap[2], true)
        + '</code>';
      continue;
    }

    // br
    if (cap = inline.br.exec(src)) {
      src = src.substring(cap[0].length);
      out += '<br>';
      continue;
    }

    // text
    if (cap = inline.text.exec(src)) {
      src = src.substring(cap[0].length);
      out += escape(cap[0]);
      continue;
    }
  }

  return out;
};

var outputLink = function(cap, link) {
  if (cap[0][0] !== '!') {
    return '<a href="'
      + escape(link.href)
      + '"'
      + (link.title
      ? ' title="'
      + escape(link.title)
      + '"'
      : '')
      + '>'
      + inline.lexer(cap[1])
      + '</a>';
  } else {
    return '<img src="'
      + escape(link.href)
      + '" alt="'
      + escape(cap[1])
      + '"'
      + (link.title
      ? ' title="'
      + escape(link.title)
      + '"'
      : '')
      + '>';
  }
};

/**
 * Parsing
 */

var tokens
  , token;

var next = function() {
  return token = tokens.pop();
};

var tok = function() {
  switch (token.type) {
    case 'space': {
      return '';
    }
    case 'hr': {
      return '<hr>\n';
    }
    case 'heading': {
      return '<h'
        + token.depth
        + '>'
        + inline.lexer(token.text)
        + '</h'
        + token.depth
        + '>\n';
    }
    case 'code': {
      return '<pre><code'
        + (token.lang
        ? ' class="'
        + token.lang
        + '"'
        : '')
        + '>'
        + (token.escaped
        ? token.text
        : escape(token.text, true))
        + '</code></pre>\n';
    }
    case 'blockquote_start': {
      var body = '';

      while (next().type !== 'blockquote_end') {
        body += tok();
      }

      return '<blockquote>\n'
        + body
        + '</blockquote>\n';
    }
    case 'list_start': {
      var type = token.ordered ? 'ol' : 'ul'
        , body = '';

      while (next().type !== 'list_end') {
        body += tok();
      }

      return '<'
        + type
        + '>\n'
        + body
        + '</'
        + type
        + '>\n';
    }
    case 'list_item_start': {
      var body = '';

      while (next().type !== 'list_item_end') {
        body += token.type === 'text'
          ? parseText()
          : tok();
      }

      return '<li>'
        + body
        + '</li>\n';
    }
    case 'loose_item_start': {
      var body = '';

      while (next().type !== 'list_item_end') {
        body += tok();
      }

      return '<li>'
        + body
        + '</li>\n';
    }
    case 'html': {
      return inline.lexer(token.text);
    }
    case 'paragraph': {
      return '<p>'
        + inline.lexer(token.text)
        + '</p>\n';
    }
    case 'text': {
      return '<p>'
        + parseText()
        + '</p>\n';
    }
  }
};

var parseText = function() {
  var body = token.text
    , top;

  while ((top = tokens[tokens.length-1])
         && top.type === 'text') {
    body += '\n' + next().text;
  }

  return inline.lexer(body);
};

var parse = function(src) {
  tokens = src.reverse();

  var out = '';
  while (next()) {
    out += tok();
  }

  tokens = null;
  token = null;

  return out;
};

/**
 * Helpers
 */

var escape = function(html, encode) {
  return html
    .replace(!encode ? /&(?!#?\w+;)/g : /&/g, '&amp;')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;')
    .replace(/'/g, '&#39;');
};

var mangle = function(text) {
  var out = ''
    , l = text.length
    , i = 0
    , ch;

  for (; i < l; i++) {
    ch = text.charCodeAt(i);
    if (Math.random() > 0.5) {
      ch = 'x' + ch.toString(16);
    }
    out += '&#' + ch + ';';
  }

  return out;
};

function tag() {
  var tag = '(?!(?:'
    + 'a|em|strong|small|s|cite|q|dfn|abbr|data|time|code'
    + '|var|samp|kbd|sub|sup|i|b|u|mark|ruby|rt|rp|bdi|bdo'
    + '|span|br|wbr|ins|del|img)\\b)\\w+';

  return tag;
}

/**
 * Expose
 */

var marked = function(src) {
  return parse(block.lexer(src));
};

marked.parser = parse;
marked.lexer = block.lexer;

marked.parse = marked;

if (typeof module !== 'undefined') {
  module.exports = marked;
} else {
  this.marked = marked;
}

}).call(this);