// stmd.js - CommomMark in javascript
// Copyright (C) 2014 John MacFarlane
// License: BSD3.
// Basic usage:
//
// var stmd = require('stmd');
// var parser = new stmd.DocParser();
// var renderer = new stmd.HtmlRenderer();
// console.log(renderer.render(parser.parse('Hello *world*')));
(function(exports) {
// Some regexps used in inline parser:
var ESCAPABLE = '[!"#$%&\'()*+,./:;<=>?@[\\\\\\]^_`{|}~-]';
var ESCAPED_CHAR = '\\\\' + ESCAPABLE;
var IN_DOUBLE_QUOTES = '"(' + ESCAPED_CHAR + '|[^"\\x00])*"';
var IN_SINGLE_QUOTES = '\'(' + ESCAPED_CHAR + '|[^\'\\x00])*\'';
var IN_PARENS = '\\((' + ESCAPED_CHAR + '|[^)\\x00])*\\)';
var REG_CHAR = '[^\\\\()\\x00-\\x20]';
var IN_PARENS_NOSP = '\\((' + REG_CHAR + '|' + ESCAPED_CHAR + ')*\\)';
var TAGNAME = '[A-Za-z][A-Za-z0-9]*';
var BLOCKTAGNAME = '(?:article|header|aside|hgroup|iframe|blockquote|hr|body|li|map|button|object|canvas|ol|caption|output|col|p|colgroup|pre|dd|progress|div|section|dl|table|td|dt|tbody|embed|textarea|fieldset|tfoot|figcaption|th|figure|thead|footer|footer|tr|form|ul|h1|h2|h3|h4|h5|h6|video|script|style)';
var ATTRIBUTENAME = '[a-zA-Z_:][a-zA-Z0-9:._-]*';
var UNQUOTEDVALUE = "[^\"'=<>`\\x00-\\x20]+";
var SINGLEQUOTEDVALUE = "'[^']*'";
var DOUBLEQUOTEDVALUE = '"[^"]*"';
var ATTRIBUTEVALUE = "(?:" + UNQUOTEDVALUE + "|" + SINGLEQUOTEDVALUE + "|" + DOUBLEQUOTEDVALUE + ")";
var ATTRIBUTEVALUESPEC = "(?:" + "\\s*=" + "\\s*" + ATTRIBUTEVALUE + ")";
var ATTRIBUTE = "(?:" + "\\s+" + ATTRIBUTENAME + ATTRIBUTEVALUESPEC + "?)";
var OPENTAG = "<" + TAGNAME + ATTRIBUTE + "*" + "\\s*/?>";
var CLOSETAG = "</" + TAGNAME + "\\s*[>]";
var OPENBLOCKTAG = "<" + BLOCKTAGNAME + ATTRIBUTE + "*" + "\\s*/?>";
var CLOSEBLOCKTAG = "</" + BLOCKTAGNAME + "\\s*[>]";
var HTMLCOMMENT = "<!--([^-]+|[-][^-]+)*-->";
var PROCESSINGINSTRUCTION = "[<][?].*?[?][>]";
var DECLARATION = "<![A-Z]+" + "\\s+[^>]*>";
var CDATA = "<!\\[CDATA\\[([^\\]]+|\\][^\\]]|\\]\\][^>])*\\]\\]>";
var HTMLTAG = "(?:" + OPENTAG + "|" + CLOSETAG + "|" + HTMLCOMMENT + "|" +
PROCESSINGINSTRUCTION + "|" + DECLARATION + "|" + CDATA + ")";
var HTMLBLOCKOPEN = "<(?:" + BLOCKTAGNAME + "[\\s/>]" + "|" +
"/" + BLOCKTAGNAME + "[\\s>]" + "|" + "[?!])";
var reHtmlTag = new RegExp('^' + HTMLTAG, 'i');
var reHtmlBlockOpen = new RegExp('^' + HTMLBLOCKOPEN, 'i');
var reLinkTitle = new RegExp(
'^(?:"(' + ESCAPED_CHAR + '|[^"\\x00])*"' +
'|' +
'\'(' + ESCAPED_CHAR + '|[^\'\\x00])*\'' +
'|' +
'\\((' + ESCAPED_CHAR + '|[^)\\x00])*\\))');
var reLinkDestinationBraces = new RegExp(
'^(?:[<](?:[^<>\\n\\\\\\x00]' + '|' + ESCAPED_CHAR + '|' + '\\\\)*[>])');
var reLinkDestination = new RegExp(
'^(?:' + REG_CHAR + '+|' + ESCAPED_CHAR + '|' + IN_PARENS_NOSP + ')*');
var reEscapable = new RegExp(ESCAPABLE);
var reAllEscapedChar = new RegExp('\\\\(' + ESCAPABLE + ')', 'g');
var reEscapedChar = new RegExp('^\\\\(' + ESCAPABLE + ')');
var reAllTab = /\t/g;
var reHrule = /^(?:(?:\* *){3,}|(?:_ *){3,}|(?:- *){3,}) *$/;
// Matches a character with a special meaning in markdown,
// or a string of non-special characters. Note: we match
// clumps of _ or * or `, because they need to be handled in groups.
var reMain = /^(?:[_*`\n]+|[\[\]\\!<&*_]|(?: *[^\n `\[\]\\!<&*_]+)+|[ \n]+)/m;
// UTILITY FUNCTIONS
// Replace backslash escapes with literal characters.
var unescape = function(s) {
return s.replace(reAllEscapedChar, '$1');
};
// Returns true if string contains only space characters.
var isBlank = function(s) {
return /^\s*$/.test(s);
};
// Normalize reference label: collapse internal whitespace
// to single space, remove leading/trailing whitespace, case fold.
var normalizeReference = function(s) {
return s.trim()
.replace(/\s+/,' ')
.toUpperCase();
};
// Attempt to match a regex in string s at offset offset.
// Return index of match or null.
var matchAt = function(re, s, offset) {
var res = s.slice(offset).match(re);
if (res) {
return offset + res.index;
} else {
return null;
}
};
// Convert tabs to spaces on each line using a 4-space tab stop.
var detabLine = function(text) {
if (text.indexOf('\t') == -1) {
return text;
} else {
var lastStop = 0;
return text.replace(reAllTab, function(match, offset) {
var result = ' '.slice((offset - lastStop) % 4);
lastStop = offset + 1;
return result;
});
}
};
// INLINE PARSER
// These are methods of an InlineParser object, defined below.
// An InlineParser keeps track of a subject (a string to be
// parsed) and a position in that subject.
// If re matches at current position in the subject, advance
// position in subject and return the match; otherwise return null.
var match = function(re) {
var match = re.exec(this.subject.slice(this.pos));
if (match) {
this.pos += match.index + match[0].length;
return match[0];
} else {
return null;
}
};
// Returns the character at the current subject position, or null if
// there are no more characters.
var peek = function() {
return this.subject[this.pos] || null;
};
// Parse zero or more space characters, including at most one newline
var spnl = function() {
this.match(/^ *(?:\n *)?/);
return 1;
};
// All of the parsers below try to match something at the current position
// in the subject. If they succeed in matching anything, they
// return the inline matched, advancing the subject.
// Attempt to parse backticks, returning either a backtick code span or a
// literal sequence of backticks.
var parseBackticks = function() {
var startpos = this.pos;
var ticks = this.match(/^`+/);
if (!ticks) {
return 0;
}
var afterOpenTicks = this.pos;
var foundCode = false;
var match;
while (!foundCode && (match = this.match(/`+/m))) {
if (match == ticks) {
return [{ t: 'Code', c: this.subject.slice(afterOpenTicks,
this.pos - ticks.length)
.replace(/[ \n]+/g,' ')
.trim() }];
}
}
// If we got here, we didn't match a closing backtick sequence.
this.pos = afterOpenTicks;
return [{ t: 'Str', c: ticks }];
};
// Parse a backslash-escaped special character, adding either the escaped
// character, a hard line break (if the backslash is followed by a newline),
// or a literal backslash to the 'inlines' list.
var parseBackslash = function() {
var subj = this.subject,
pos = this.pos;
if (subj[pos] === '\\') {
if (subj[pos + 1] === '\n') {
this.pos = this.pos + 2;
return [{ t: 'Hardbreak' }];
} else if (reEscapable.test(subj[pos + 1])) {
this.pos = this.pos + 2;
return [{ t: 'Str', c: subj[pos + 1] }];
} else {
this.pos++;
return [{t: 'Str', c: '\\'}];
}
} else {
return null;
}
};
// Attempt to parse an autolink (URL or email in pointy brackets).
var parseAutolink = function() {
var m;
var dest;
if ((m = this.match(/^<([a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*)>/))) { // email autolink
dest = m.slice(1,-1);
return [{t: 'Link',
label: [{ t: 'Str', c: dest }],
destination: 'mailto:' + dest }];
} else if ((m = this.match(/^<(?:coap|doi|javascript|aaa|aaas|about|acap|cap|cid|crid|data|dav|dict|dns|file|ftp|geo|go|gopher|h323|http|https|iax|icap|im|imap|info|ipp|iris|iris.beep|iris.xpc|iris.xpcs|iris.lwz|ldap|mailto|mid|msrp|msrps|mtqp|mupdate|news|nfs|ni|nih|nntp|opaquelocktoken|pop|pres|rtsp|service|session|shttp|sieve|sip|sips|sms|snmp|soap.beep|soap.beeps|tag|tel|telnet|tftp|thismessage|tn3270|tip|tv|urn|vemmi|ws|wss|xcon|xcon-userid|xmlrpc.beep|xmlrpc.beeps|xmpp|z39.50r|z39.50s|adiumxtra|afp|afs|aim|apt|attachment|aw|beshare|bitcoin|bolo|callto|chrome|chrome-extension|com-eventbrite-attendee|content|cvs|dlna-playsingle|dlna-playcontainer|dtn|dvb|ed2k|facetime|feed|finger|fish|gg|git|gizmoproject|gtalk|hcp|icon|ipn|irc|irc6|ircs|itms|jar|jms|keyparc|lastfm|ldaps|magnet|maps|market|message|mms|ms-help|msnim|mumble|mvn|notes|oid|palm|paparazzi|platform|proxy|psyc|query|res|resource|rmi|rsync|rtmp|secondlife|sftp|sgn|skype|smb|soldat|spotify|ssh|steam|svn|teamspeak|things|udp|unreal|ut2004|ventrilo|view-source|webcal|wtai|wyciwyg|xfire|xri|ymsgr):[^<>\x00-\x20]*>/i))) {
dest = m.slice(1,-1);
return [{ t: 'Link',
label: [{ t: 'Str', c: dest }],
destination: dest }];
} else {
return null;
}
};
// Attempt to parse a raw HTML tag.
var parseHtmlTag = function() {
var m = this.match(reHtmlTag);
if (m) {
return [{ t: 'Html', c: m }];
} else {
return null;
}
};
// Scan a sequence of characters == c, and return information about
// the number of delimiters and whether they are positioned such that
// they can open and/or close emphasis or strong emphasis. A utility
// function for strong/emph parsing.
var scanDelims = function(c) {
var numdelims = 0;
var first_close_delims = 0;
var char_before, char_after;
var startpos = this.pos;
char_before = this.pos === 0 ? '\n' :
this.subject[this.pos - 1];
while (this.peek() === c) {
numdelims++;
this.pos++;
}
char_after = this.peek() || '\n';
var can_open = numdelims > 0 && numdelims <= 3 && !(/\s/.test(char_after));
var can_close = numdelims > 0 && numdelims <= 3 && !(/\s/.test(char_before));
if (c === '_') {
can_open = can_open && !((/[a-z0-9]/i).test(char_before));
can_close = can_close && !((/[a-z0-9]/i).test(char_after));
}
this.pos = startpos;
return { numdelims: numdelims,
can_open: can_open,
can_close: can_close };
};
// Attempt to parse emphasis or strong emphasis.
var parseEmphasis = function() {
var startpos = this.pos;
var c ;
var first_close = 0;
c = this.peek();
if (!(c === '*' || c === '_')) {
return null;
}
var numdelims;
var delimpos;
var inlines = [];
// Get opening delimiters.
res = this.scanDelims(c);
numdelims = res.numdelims;
if (numdelims === 0) {
this.pos = startpos;
return null;
}
if (numdelims >= 4 || !res.can_open) {
this.pos += numdelims;
return [{t: 'Str', c: this.subject.slice(startpos, startpos + numdelims)}];
}
this.pos += numdelims;
var next_inline;
var first = [];
var second = [];
var current = first;
var state = 0;
var can_close = false;
var can_open = false;
if (numdelims === 3) {
state = 1;
} else if (numdelims === 2) {
state = 2;
} else if (numdelims === 1) {
state = 3;
}
while (true) {
res = this.scanDelims(c);
if (res) {
numdelims = res.numdelims;
can_close = res.can_close;
can_open = res.can_open;
switch (state) {
case 1: // ***a
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong', c: [{t: 'Emph', c: first}]}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
current = second;
state = can_open ? 4 : 6;
continue;
} else if (numdelims === 1 && can_close) {
this.pos += 1;
current = second;
state = can_open ? 5 : 7;
continue;
}
break;
case 2: // **a
if (numdelims === 2 && can_close) {
this.pos += 2;
return [{t: 'Strong', c: first}];
} else if (numdelims === 1 && can_open) {
this.pos += 1;
current = second;
state = 8;
continue;
}
break;
case 3: // *a
if (numdelims === 1 && can_close) {
this.pos += 1;
return [{t: 'Emph', c: first}];
} else if (numdelims === 2 && can_open) {
this.pos += 2;
current = second;
state = 9;
continue;
}
break;
case 4: // ***a**b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong',
c: [{t: 'Emph',
c: first.concat(
[{t: 'Str', c: c+c}],
second)}]}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
return [{t: 'Strong',
c: [{t: 'Str', c: c+c+c}].concat(
first,
[{t: 'Strong', c: second}])}];
} else if (numdelims === 1 && can_close) {
this.pos += 1;
return [{t: 'Emph',
c: [{t: 'Strong', c: first}].concat(second)}];
}
break;
case 5: // ***a*b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong',
c: [{t: 'Emph',
c: first.concat(
[{t: 'Str', c: c}],
second)}]}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
return [{t: 'Strong',
c: [{t: 'Emph', c: first}].concat(second)}];
} else if (numdelims === 1 && can_close) {
this.pos += 1;
return [{t: 'Strong',
c: [{t: 'Str', c: c+c+c}].concat(
first,
[{t: 'Emph', c: second}])}];
}
break;
case 6: // ***a** b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong',
c: [{t: 'Emph',
c: first.concat(
[{t: 'Str', c: c+c}],
second)}]}];
} else if (numdelims === 1 && can_close) {
this.pos += 1;
return [{t: 'Emph',
c: [{t: 'Strong', c: first}].concat(second)}];
}
break;
case 7: // ***a* b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong',
c: [{t: 'Emph',
c: first.concat(
[{t: 'Str', c: c}],
second)}]}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
return [{t: 'Strong',
c: [{t: 'Emph', c: first}].concat(second)}];
}
break;
case 8: // **a *b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Strong',
c: first.concat([{t: 'Emph',
c: second}])}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
return [{t: 'Strong',
c: first.concat(
[{t: 'Str', c: c}],
second)}];
} else if (numdelims === 1 && can_close) {
this.pos += 1;
first = first.concat([{t: 'Emph', c: second}]);
current = first;
state = 2;
continue;
}
break;
case 9: // *a **b
if (numdelims === 3 && can_close) {
this.pos += 3;
return [{t: 'Emph',
c: first.concat([{t: 'Strong',
c: second}])}];
} else if (numdelims === 2 && can_close) {
this.pos += 2;
first = first.concat([{t: 'Strong', c: second}]);
current = first;
state = 3;
continue;
} else if (numdelims === 1 && can_close) {
this.pos += 1;
return [{t: 'Emph',
c: first.concat(
[{t: 'Str', c: c+c}],
second)}];
}
break;
default:
break;
}
}
if ((next_inline = this.parseInline())) {
Array.prototype.push.apply(current, next_inline);
} else {
break;
}
}
switch (state) {
case 1: // ***a
return [{t: 'Str', c: c+c+c}].concat(first);
case 2: // **a
return [{t: 'Str', c: c+c}].concat(first);
case 3: // *a
return [{t: 'Str', c: c}].concat(first);
case 4: // ***a**b
case 6: // ***a** b
return [{t: 'Str', c: c+c+c}]
.concat(first,
[{t: 'Str', c: c+c}],
second);
case 5: // ***a*b
case 7: // ***a* b
return [{t: 'Str', c: c+c+c}]
.concat(first,
[{t: 'Str', c: c}],
second);
case 8: // **a *b
return [{t: 'Str', c: c+c}]
.concat(first,
[{t: 'Str', c: c}],
second);
case 9: // *a **b
return [{t: 'Str', c: c}]
.concat(first,
[{t: 'Str', c: c+c}],
second);
default:
console.log("Unknown state, parseEmphasis");
// shouldn't happen
}
};
// Attempt to parse link title (sans quotes), returning the string
// or null if no match.
var parseLinkTitle = function() {
var title = this.match(reLinkTitle);
if (title) {
// chop off quotes from title and unescape:
return unescape(title.substr(1, title.length - 2));
} else {
return null;
}
};
// Attempt to parse link destination, returning the string or
// null if no match.
var parseLinkDestination = function() {
var res = this.match(reLinkDestinationBraces);
if (res) { // chop off surrounding <..>:
return unescape(res.substr(1, res.length - 2));
} else {
res = this.match(reLinkDestination);
if (res !== null) {
return unescape(res);
} else {
return null;
}
}
};
// Attempt to parse a link label, returning number of characters parsed.
var parseLinkLabel = function() {
if (this.peek() != '[') {
return 0;
}
var startpos = this.pos;
var nest_level = 0;
if (this.label_nest_level > 0) {
// If we've already checked to the end of this subject
// for a label, even with a different starting [, we
// know we won't find one here and we can just return.
// This avoids lots of backtracking.
// Note: nest level 1 would be: [foo [bar]
// nest level 2 would be: [foo [bar [baz]
this.label_nest_level--;
return 0;
}
this.pos++; // advance past [
var c;
while ((c = this.peek()) && (c != ']' || nest_level > 0)) {
switch (c) {
case '`':
this.parseBackticks();
break;
case '<':
if (!(this.parseAutolink())) {
this.parseHtmlTag();
}
break;
case '[': // nested []
nest_level++;
this.pos++;
break;
case ']': // nested []
nest_level--;
this.pos++;
break;
case '\\':
this.parseBackslash();
break;
default:
this.parseString();
}
}
if (c === ']') {
this.label_nest_level = 0;
this.pos++; // advance past ]
return this.pos - startpos;
} else {
if (!c) {
this.label_nest_level = nest_level;
}
this.pos = startpos;
return 0;
}
};
// Parse raw link label, including surrounding [], and return
// inline contents. (Note: this is not a method of InlineParser.)
var parseRawLabel = function(s) {
// note: parse without a refmap; we don't want links to resolve
// in nested brackets!
return new InlineParser().parse(s.substr(1, s.length - 2), {});
};
// Attempt to parse a link. If successful, return the link.
var parseLink = function() {
var startpos = this.pos;
var reflabel;
var n;
var dest;
var title;
n = this.parseLinkLabel();
if (n === 0) {
return null;
}
var afterlabel = this.pos;
var rawlabel = this.subject.substr(startpos, n);
// if we got this far, we've parsed a label.
// Try to parse an explicit link: [label](url "title")
if (this.peek() == '(') {
this.pos++;
if (this.spnl() &&
((dest = this.parseLinkDestination()) !== null) &&
this.spnl() &&
// make sure there's a space before the title:
(/^\s/.test(this.subject[this.pos - 1]) &&
(title = this.parseLinkTitle() || '') || true) &&
this.spnl() &&
this.match(/^\)/)) {
return [{ t: 'Link',
destination: dest,
title: title,
label: parseRawLabel(rawlabel) }];
} else {
this.pos = startpos;
return null;
}
}
// If we're here, it wasn't an explicit link. Try to parse a reference link.
// first, see if there's another label
var savepos = this.pos;
this.spnl();
var beforelabel = this.pos;
n = this.parseLinkLabel();
if (n == 2) {
// empty second label
reflabel = rawlabel;
} else if (n > 0) {
reflabel = this.subject.slice(beforelabel, beforelabel + n);
} else {
this.pos = savepos;
reflabel = rawlabel;
}
// lookup rawlabel in refmap
var link = this.refmap[normalizeReference(reflabel)];
if (link) {
return [{t: 'Link',
destination: link.destination,
title: link.title,
label: parseRawLabel(rawlabel) }];
} else {
this.pos = startpos;
return null;
}
// Nothing worked, rewind:
this.pos = startpos;
return null;
};
// Attempt to parse an entity, return Entity object if successful.
var parseEntity = function() {
var m;
if ((m = this.match(/^&(?:#x[a-f0-9]{1,8}|#[0-9]{1,8}|[a-z][a-z0-9]{1,31});/i))) {
return [{ t: 'Entity', c: m }];
} else {
return null;
}
};
// Parse a run of ordinary characters, or a single character with
// a special meaning in markdown, as a plain string, adding to inlines.
var parseString = function() {
var m;
if ((m = this.match(reMain))) {
return [{ t: 'Str', c: m }];
} else {
return null;
}
};
// Parse a newline. If it was preceded by two spaces, return a hard
// line break; otherwise a soft line break.
var parseNewline = function() {
var m = this.match(/^ *\n/);
if (m) {
if (m.length > 2) {
return [{ t: 'Hardbreak' }];
} else if (m.length > 0) {
return [{ t: 'Softbreak' }];
}
}
return null;
};
// Attempt to parse an image. If the opening '!' is not followed
// by a link, return a literal '!'.
var parseImage = function() {
if (this.match(/^!/)) {
var link = this.parseLink();
if (link) {
link[0].t = 'Image';
return link;
} else {
return [{ t: 'Str', c: '!' }];
}
} else {
return null;
}
};
// Attempt to parse a link reference, modifying refmap.
var parseReference = function(s, refmap) {
this.subject = s;
this.pos = 0;
var rawlabel;
var dest;
var title;
var matchChars;
var startpos = this.pos;
var match;
// label:
matchChars = this.parseLinkLabel();
if (matchChars === 0) {
return 0;
} else {
rawlabel = this.subject.substr(0, matchChars);
}
// colon:
if (this.peek() === ':') {
this.pos++;
} else {
this.pos = startpos;
return 0;
}
// link url
this.spnl();
dest = this.parseLinkDestination();
if (dest === null || dest.length === 0) {
this.pos = startpos;
return 0;
}
var beforetitle = this.pos;
this.spnl();
title = this.parseLinkTitle();
if (title === null) {
title = '';
// rewind before spaces
this.pos = beforetitle;
}
// make sure we're at line end:
if (this.match(/^ *(?:\n|$)/) === null) {
this.pos = startpos;
return 0;
}
var normlabel = normalizeReference(rawlabel);
if (!refmap[normlabel]) {
refmap[normlabel] = { destination: dest, title: title };
}
return this.pos - startpos;
};
// Parse the next inline element in subject, advancing subject position
// and returning the inline parsed.
var parseInline = function() {
var startpos = this.pos;
/*
var memoized = this.memo[startpos];
if (memoized) {
this.pos = memoized.endpos;
return memoized.inline;
}
*/
var c = this.peek();
if (!c) {
return null;
}
var res;
switch(c) {
case '\n':
case ' ':
res = this.parseNewline();
break;
case '\\':
res = this.parseBackslash();
break;
case '`':
res = this.parseBackticks();
break;
case '*':
case '_':
res = this.parseEmphasis();
break;
case '[':
res = this.parseLink();
break;
case '!':
res = this.parseImage();
break;
case '<':
res = this.parseAutolink() || this.parseHtmlTag();
break;
case '&':
res = this.parseEntity();
break;
default:
res = this.parseString();
break;
}
if (res === null) {
this.pos += 1;
res = [{t: 'Str', c: c}];
}
/*
if (res) {
this.memo[startpos] = { inline: res,
endpos: this.pos };
}
*/
return res;
};
// Parse s as a list of inlines, using refmap to resolve references.
var parseInlines = function(s, refmap) {
this.subject = s;
this.pos = 0;
this.refmap = refmap || {};
// this.memo = {};
this.last_emphasis_closer = null;
var inlines = [];
var next_inline;
while ((next_inline = this.parseInline())) {
Array.prototype.push.apply(inlines, next_inline);
}
return inlines;
};
// The InlineParser object.
function InlineParser(){
return {
subject: '',
label_nest_level: 0, // used by parseLinkLabel method
last_emphasis_closer: null, // used by parseEmphasis method
pos: 0,
refmap: {},
// memo: {},
match: match,
peek: peek,
spnl: spnl,
parseBackticks: parseBackticks,
parseBackslash: parseBackslash,
parseAutolink: parseAutolink,
parseHtmlTag: parseHtmlTag,
scanDelims: scanDelims,
parseEmphasis: parseEmphasis,
parseLinkTitle: parseLinkTitle,
parseLinkDestination: parseLinkDestination,
parseLinkLabel: parseLinkLabel,
parseLink: parseLink,
parseEntity: parseEntity,
parseString: parseString,
parseNewline: parseNewline,
parseImage: parseImage,
parseReference: parseReference,
parseInline: parseInline,
parse: parseInlines
};
}
// DOC PARSER
// These are methods of a DocParser object, defined below.
var makeBlock = function(tag, start_line, start_column) {
return { t: tag,
open: true,
last_line_blank: false,
start_line: start_line,
start_column: start_column,
end_line: start_line,
children: [],
parent: null,
// string_content is formed by concatenating strings, in finalize:
string_content: "",
strings: [],
inline_content: []
};
};
// Returns true if parent block can contain child block.
var canContain = function(parent_type, child_type) {
return ( parent_type == 'Document' ||
parent_type == 'BlockQuote' ||
parent_type == 'ListItem' ||
(parent_type == 'List' && child_type == 'ListItem') );
};
// Returns true if block type can accept lines of text.
var acceptsLines = function(block_type) {
return ( block_type == 'Paragraph' ||
block_type == 'IndentedCode' ||
block_type == 'FencedCode' );
};
// Returns true if block ends with a blank line, descending if needed
// into lists and sublists.
var endsWithBlankLine = function(block) {
if (block.last_line_blank) {
return true;
}
if ((block.t == 'List' || block.t == 'ListItem') && block.children.length > 0) {
return endsWithBlankLine(block.children[block.children.length - 1]);
} else {
return false;
}
};
// Break out of all containing lists, resetting the tip of the
// document to the parent of the highest list, and finalizing
// all the lists. (This is used to implement the "two blank lines
// break of of all lists" feature.)
var breakOutOfLists = function(block, line_number) {
var b = block;
var last_list = null;
do {
if (b.t === 'List') {
last_list = b;
}
b = b.parent;
} while (b);
if (last_list) {
while (block != last_list) {
this.finalize(block, line_number);
block = block.parent;
}
this.finalize(last_list, line_number);
this.tip = last_list.parent;
}
};
// Add a line to the block at the tip. We assume the tip
// can accept lines -- that check should be done before calling this.
var addLine = function(ln, offset) {
var s = ln.slice(offset);
if (!(this.tip.open)) {
throw({ msg: "Attempted to add line (" + ln + ") to closed container." });
}
this.tip.strings.push(s);
};
// Add block of type tag as a child of the tip. If the tip can't
// accept children, close and finalize it and try its parent,
// and so on til we find a block that can accept children.
var addChild = function(tag, line_number, offset) {
while (!canContain(this.tip.t, tag)) {
this.finalize(this.tip, line_number);
}
var column_number = offset + 1; // offset 0 = column 1
var newBlock = makeBlock(tag, line_number, column_number);
this.tip.children.push(newBlock);
newBlock.parent = this.tip;
this.tip = newBlock;
return newBlock;
};
// Parse a list marker and return data on the marker (type,
// start, delimiter, bullet character, padding) or null.
var parseListMarker = function(ln, offset) {
var rest = ln.slice(offset);
var match;
var spaces_after_marker;
var data = {};
if (rest.match(reHrule)) {
return null;
}
if ((match = rest.match(/^[*+-]( +|$)/))) {
spaces_after_marker = match[1].length;
data.type = 'Bullet';
data.bullet_char = match[0][0];
} else if ((match = rest.match(/^(\d+)([.)])( +|$)/))) {
spaces_after_marker = match[3].length;
data.type = 'Ordered';
data.start = parseInt(match[1]);
data.delimiter = match[2];
} else {
return null;
}
var blank_item = match[0].length === rest.length;
if (spaces_after_marker >= 5 ||
spaces_after_marker < 1 ||
blank_item) {
data.padding = match[0].length - spaces_after_marker + 1;
} else {
data.padding = match[0].length;
}
return data;
};
// Returns true if the two list items are of the same type,
// with the same delimiter and bullet character. This is used
// in agglomerating list items into lists.
var listsMatch = function(list_data, item_data) {
return (list_data.type === item_data.type &&
list_data.delimiter === item_data.delimiter &&
list_data.bullet_char === item_data.bullet_char);
};
// Analyze a line of text and update the document appropriately.
// We parse markdown text by calling this on each line of input,
// then finalizing the document.
var incorporateLine = function(ln, line_number) {
var all_matched = true;
var last_child;
var first_nonspace;
var offset = 0;
var match;
var data;
var blank;
var indent;
var last_matched_container;
var i;
var CODE_INDENT = 4;
var container = this.doc;
var oldtip = this.tip;
// Convert tabs to spaces:
ln = detabLine(ln);
// For each containing block, try to parse the associated line start.
// Bail out on failure: container will point to the last matching block.
// Set all_matched to false if not all containers match.
while (container.children.length > 0) {
last_child = container.children[container.children.length - 1];
if (!last_child.open) {
break;
}
container = last_child;
match = matchAt(/[^ ]/, ln, offset);
if (match === null) {
first_nonspace = ln.length;
blank = true;
} else {
first_nonspace = match;
blank = false;
}
indent = first_nonspace - offset;
switch (container.t) {
case 'BlockQuote':
var matched = indent <= 3 && ln[first_nonspace] === '>';
if (matched) {
offset = first_nonspace + 1;
if (ln[offset] === ' ') {
offset++;
}
} else {
all_matched = false;
}
break;
case 'ListItem':
if (indent >= container.list_data.marker_offset +
container.list_data.padding) {
offset += container.list_data.marker_offset +
container.list_data.padding;
} else if (blank) {
offset = first_nonspace;
} else {
all_matched = false;
}
break;
case 'IndentedCode':
if (indent >= CODE_INDENT) {
offset += CODE_INDENT;
} else if (blank) {
offset = first_nonspace;
} else {
all_matched = false;
}
break;
case 'ATXHeader':
case 'SetextHeader':
case 'HorizontalRule':
// a header can never container > 1 line, so fail to match:
all_matched = false;
break;
case 'FencedCode':
// skip optional spaces of fence offset
i = container.fence_offset;
while (i > 0 && ln[offset] === ' ') {
offset++;
i--;
}
break;
case 'HtmlBlock':
if (blank) {
all_matched = false;
}
break;
case 'Paragraph':
if (blank) {
container.last_line_blank = true;
all_matched = false;
}
break;
default:
}
if (!all_matched) {
container = container.parent; // back up to last matching block
break;
}
}
last_matched_container = container;
// This function is used to finalize and close any unmatched
// blocks. We aren't ready to do this now, because we might
// have a lazy paragraph continuation, in which case we don't
// want to close unmatched blocks. So we store this closure for
// use later, when we have more information.
var closeUnmatchedBlocks = function(mythis) {
// finalize any blocks not matched
while (!already_done && oldtip != last_matched_container) {
mythis.finalize(oldtip, line_number);
oldtip = oldtip.parent;
}
var already_done = true;
};
// Check to see if we've hit 2nd blank line; if so break out of list:
if (blank && container.last_line_blank) {
this.breakOutOfLists(container, line_number);
}
// Unless last matched container is a code block, try new container starts,
// adding children to the last matched container:
while (container.t != 'FencedCode' &&
container.t != 'IndentedCode' &&
container.t != 'HtmlBlock' &&
// this is a little performance optimization:
matchAt(/^[ #`~*+_=<>0-9-]/,ln,offset) !== null) {
match = matchAt(/[^ ]/, ln, offset);
if (match === null) {
first_nonspace = ln.length;
blank = true;
} else {
first_nonspace = match;
blank = false;
}
indent = first_nonspace - offset;
if (indent >= CODE_INDENT) {
// indented code
if (this.tip.t != 'Paragraph' && !blank) {
offset += CODE_INDENT;
closeUnmatchedBlocks(this);
container = this.addChild('IndentedCode', line_number, offset);
} else { // indent > 4 in a lazy paragraph continuation
break;
}
} else if (ln[first_nonspace] === '>') {
// blockquote
offset = first_nonspace + 1;
// optional following space
if (ln[offset] === ' ') {
offset++;
}
closeUnmatchedBlocks(this);
container = this.addChild('BlockQuote', line_number, offset);
} else if ((match = ln.slice(first_nonspace).match(/^#{1,6}(?: +|$)/))) {
// ATX header
offset = first_nonspace + match[0].length;
closeUnmatchedBlocks(this);
container = this.addChild('ATXHeader', line_number, first_nonspace);
container.level = match[0].trim().length; // number of #s
// remove trailing ###s:
container.strings =
[ln.slice(offset).replace(/(?:(\\#) *#*| *#+) *$/,'$1')];
break;
} else if ((match = ln.slice(first_nonspace).match(/^`{3,}(?!.*`)|^~{3,}(?!.*~)/))) {
// fenced code block
var fence_length = match[0].length;
closeUnmatchedBlocks(this);
container = this.addChild('FencedCode', line_number, first_nonspace);
container.fence_length = fence_length;
container.fence_char = match[0][0];
container.fence_offset = first_nonspace - offset;
offset = first_nonspace + fence_length;
break;
} else if (matchAt(reHtmlBlockOpen, ln, first_nonspace) !== null) {
// html block
closeUnmatchedBlocks(this);
container = this.addChild('HtmlBlock', line_number, first_nonspace);
// note, we don't adjust offset because the tag is part of the text
break;
} else if (container.t == 'Paragraph' &&
container.strings.length === 1 &&
((match = ln.slice(first_nonspace).match(/^(?:=+|-+) *$/)))) {
// setext header line
closeUnmatchedBlocks(this);
container.t = 'SetextHeader'; // convert Paragraph to SetextHeader
container.level = match[0][0] === '=' ? 1 : 2;
offset = ln.length;
} else if (matchAt(reHrule, ln, first_nonspace) !== null) {
// hrule
closeUnmatchedBlocks(this);
container = this.addChild('HorizontalRule', line_number, first_nonspace);
offset = ln.length - 1;
break;
} else if ((data = parseListMarker(ln, first_nonspace))) {
// list item
closeUnmatchedBlocks(this);
data.marker_offset = indent;
offset = first_nonspace + data.padding;
// add the list if needed
if (container.t !== 'List' ||
!(listsMatch(container.list_data, data))) {
container = this.addChild('List', line_number, first_nonspace);
container.list_data = data;
}
// add the list item
container = this.addChild('ListItem', line_number, first_nonspace);
container.list_data = data;
} else {
break;
}
if (acceptsLines(container.t)) {
// if it's a line container, it can't contain other containers
break;
}
}
// What remains at the offset is a text line. Add the text to the
// appropriate container.
match = matchAt(/[^ ]/, ln, offset);
if (match === null) {
first_nonspace = ln.length;
blank = true;
} else {
first_nonspace = match;
blank = false;
}
indent = first_nonspace - offset;
// First check for a lazy paragraph continuation:
if (this.tip !== last_matched_container &&
!blank &&
this.tip.t == 'Paragraph' &&
this.tip.strings.length > 0) {
// lazy paragraph continuation
this.last_line_blank = false;
this.addLine(ln, offset);
} else { // not a lazy continuation
// finalize any blocks not matched
closeUnmatchedBlocks(this);
// Block quote lines are never blank as they start with >
// and we don't count blanks in fenced code for purposes of tight/loose
// lists or breaking out of lists. We also don't set last_line_blank
// on an empty list item.
container.last_line_blank = blank &&
!(container.t == 'BlockQuote' ||
container.t == 'FencedCode' ||
(container.t == 'ListItem' &&
container.children.length === 0 &&
container.start_line == line_number));
var cont = container;
while (cont.parent) {
cont.parent.last_line_blank = false;
cont = cont.parent;
}
switch (container.t) {
case 'IndentedCode':
case 'HtmlBlock':
this.addLine(ln, offset);
break;
case 'FencedCode':
// check for closing code fence:
match = (indent <= 3 &&
ln[first_nonspace] == container.fence_char &&
ln.slice(first_nonspace).match(/^(?:`{3,}|~{3,})(?= *$)/));
if (match && match[0].length >= container.fence_length) {
// don't add closing fence to container; instead, close it:
this.finalize(container, line_number);
} else {
this.addLine(ln, offset);
}
break;
case 'ATXHeader':
case 'SetextHeader':
case 'HorizontalRule':
// nothing to do; we already added the contents.
break;
default:
if (acceptsLines(container.t)) {
this.addLine(ln, first_nonspace);
} else if (blank) {
// do nothing
} else if (container.t != 'HorizontalRule' &&
container.t != 'SetextHeader') {
// create paragraph container for line
container = this.addChild('Paragraph', line_number, first_nonspace);
this.addLine(ln, first_nonspace);
} else {
console.log("Line " + line_number.toString() +
" with container type " + container.t +
" did not match any condition.");
}
}
}
};
// Finalize a block. Close it and do any necessary postprocessing,
// e.g. creating string_content from strings, setting the 'tight'
// or 'loose' status of a list, and parsing the beginnings
// of paragraphs for reference definitions. Reset the tip to the
// parent of the closed block.
var finalize = function(block, line_number) {
var pos;
// don't do anything if the block is already closed
if (!block.open) {
return 0;
}
block.open = false;
if (line_number > block.start_line) {
block.end_line = line_number - 1;
} else {
block.end_line = line_number;
}
switch (block.t) {
case 'Paragraph':
block.string_content = block.strings.join('\n').replace(/^ */m,'');
// try parsing the beginning as link reference definitions:
while (block.string_content[0] === '[' &&
(pos = this.inlineParser.parseReference(block.string_content,
this.refmap))) {
block.string_content = block.string_content.slice(pos);
if (isBlank(block.string_content)) {
block.t = 'ReferenceDef';
break;
}
}
break;
case 'ATXHeader':
case 'SetextHeader':
case 'HtmlBlock':
block.string_content = block.strings.join('\n');
break;
case 'IndentedCode':
block.string_content = block.strings.join('\n').replace(/(\n *)*$/,'\n');
break;
case 'FencedCode':
// first line becomes info string
block.info = unescape(block.strings[0].trim());
if (block.strings.length == 1) {
block.string_content = '';
} else {
block.string_content = block.strings.slice(1).join('\n') + '\n';
}
break;
case 'List':
block.tight = true; // tight by default
var numitems = block.children.length;
var i = 0;
while (i < numitems) {
var item = block.children[i];
// check for non-final list item ending with blank line:
var last_item = i == numitems - 1;
if (endsWithBlankLine(item) && !last_item) {
block.tight = false;
break;
}
// recurse into children of list item, to see if there are
// spaces between any of them:
var numsubitems = item.children.length;
var j = 0;
while (j < numsubitems) {
var subitem = item.children[j];
var last_subitem = j == numsubitems - 1;
if (endsWithBlankLine(subitem) && !(last_item && last_subitem)) {
block.tight = false;
break;
}
j++;
}
i++;
}
break;
default:
break;
}
this.tip = block.parent || this.top;
};
// Walk through a block & children recursively, parsing string content
// into inline content where appropriate.
var processInlines = function(block) {
switch(block.t) {
case 'Paragraph':
case 'SetextHeader':
case 'ATXHeader':
block.inline_content =
this.inlineParser.parse(block.string_content.trim(), this.refmap);
block.string_content = "";
break;
default:
break;
}
if (block.children) {
for (var i = 0; i < block.children.length; i++) {
this.processInlines(block.children[i]);
}
}
};
// The main parsing function. Returns a parsed document AST.
var parse = function(input) {
this.doc = makeBlock('Document', 1, 1);
this.tip = this.doc;
this.refmap = {};
var lines = input.replace(/\n$/,'').split(/\r\n|\n|\r/);
var len = lines.length;
for (var i = 0; i < len; i++) {
this.incorporateLine(lines[i], i+1);
}
while (this.tip) {
this.finalize(this.tip, len - 1);
}
this.processInlines(this.doc);
return this.doc;
};
// The DocParser object.
function DocParser(){
return {
doc: makeBlock('Document', 1, 1),
tip: this.doc,
refmap: {},
inlineParser: new InlineParser(),
breakOutOfLists: breakOutOfLists,
addLine: addLine,
addChild: addChild,
incorporateLine: incorporateLine,
finalize: finalize,
processInlines: processInlines,
parse: parse
};
}
// HTML RENDERER
// Helper function to produce content in a pair of HTML tags.
var inTags = function(tag, attribs, contents, selfclosing) {
var result = '<' + tag;
if (attribs) {
var i = 0;
var attrib;
while ((attrib = attribs[i]) !== undefined) {
result = result.concat(' ', attrib[0], '="', attrib[1], '"');
i++;
}
}
if (contents) {
result = result.concat('>', contents, '</', tag, '>');
} else if (selfclosing) {
result = result + ' />';
} else {
result = result.concat('></', tag, '>');
}
return result;
};
// Render an inline element as HTML.
var renderInline = function(inline) {
var attrs;
switch (inline.t) {
case 'Str':
return this.escape(inline.c);
case 'Softbreak':
return this.softbreak;
case 'Hardbreak':
return inTags('br',[],"",true) + '\n';
case 'Emph':
return inTags('em', [], this.renderInlines(inline.c));
case 'Strong':
return inTags('strong', [], this.renderInlines(inline.c));
case 'Html':
return inline.c;
case 'Entity':
return inline.c;
case 'Link':
attrs = [['href', this.escape(inline.destination, true)]];
if (inline.title) {
attrs.push(['title', this.escape(inline.title, true)]);
}
return inTags('a', attrs, this.renderInlines(inline.label));
case 'Image':
attrs = [['src', this.escape(inline.destination, true)],
['alt', this.escape(this.renderInlines(inline.label))]];
if (inline.title) {
attrs.push(['title', this.escape(inline.title, true)]);
}
return inTags('img', attrs, "", true);
case 'Code':
return inTags('code', [], this.escape(inline.c));
default:
console.log("Unknown inline type " + inline.t);
return "";
}
};
// Render a list of inlines.
var renderInlines = function(inlines) {
var result = '';
for (var i=0; i < inlines.length; i++) {
result = result + this.renderInline(inlines[i]);
}
return result;
};
// Render a single block element.
var renderBlock = function(block, in_tight_list) {
var tag;
var attr;
var info_words;
switch (block.t) {
case 'Document':
var whole_doc = this.renderBlocks(block.children);
return (whole_doc === '' ? '' : whole_doc + '\n');
case 'Paragraph':
if (in_tight_list) {
return this.renderInlines(block.inline_content);
} else {
return inTags('p', [], this.renderInlines(block.inline_content));
}
break;
case 'BlockQuote':
var filling = this.renderBlocks(block.children);
return inTags('blockquote', [], filling === '' ? this.innersep :
this.innersep + this.renderBlocks(block.children) + this.innersep);
case 'ListItem':
return inTags('li', [], this.renderBlocks(block.children, in_tight_list).trim());
case 'List':
tag = block.list_data.type == 'Bullet' ? 'ul' : 'ol';
attr = (!block.list_data.start || block.list_data.start == 1) ?
[] : [['start', block.list_data.start.toString()]];
return inTags(tag, attr, this.innersep +
this.renderBlocks(block.children, block.tight) +
this.innersep);
case 'ATXHeader':
case 'SetextHeader':
tag = 'h' + block.level;
return inTags(tag, [], this.renderInlines(block.inline_content));
case 'IndentedCode':
return inTags('pre', [],
inTags('code', [], this.escape(block.string_content)));
case 'FencedCode':
info_words = block.info.split(/ +/);
attr = info_words.length === 0 || info_words[0].length === 0 ?
[] : [['class','language-' +
this.escape(info_words[0],true)]];
return inTags('pre', [],
inTags('code', attr, this.escape(block.string_content)));
case 'HtmlBlock':
return block.string_content;
case 'ReferenceDef':
return "";
case 'HorizontalRule':
return inTags('hr',[],"",true);
default:
console.log("Unknown block type " + block.t);
return "";
}
};
// Render a list of block elements, separated by this.blocksep.
var renderBlocks = function(blocks, in_tight_list) {
var result = [];
for (var i=0; i < blocks.length; i++) {
if (blocks[i].t !== 'ReferenceDef') {
result.push(this.renderBlock(blocks[i], in_tight_list));
}
}
return result.join(this.blocksep);
};
// The HtmlRenderer object.
function HtmlRenderer(){
return {
// default options:
blocksep: '\n', // space between blocks
innersep: '\n', // space between block container tag and contents
softbreak: '\n', // by default, soft breaks are rendered as newlines in HTML
// set to "<br />" to make them hard breaks
// set to " " if you want to ignore line wrapping in source
escape: function(s, preserve_entities) {
if (preserve_entities) {
return s.replace(/[&](?;|[a-z][a-z0-9]{1,31};)/gi,'&')
.replace(/[<]/g,'<')
.replace(/[>]/g,'>')
.replace(/["]/g,'"');
} else {
return s.replace(/[&]/g,'&')
.replace(/[<]/g,'<')
.replace(/[>]/g,'>')
.replace(/["]/g,'"');
}
},
renderInline: renderInline,
renderInlines: renderInlines,
renderBlock: renderBlock,
renderBlocks: renderBlocks,
render: renderBlock
};
}
exports.DocParser = DocParser;
exports.HtmlRenderer = HtmlRenderer;
})(typeof exports === 'undefined' ? this.stmd = {} : exports);