setup-python/node_modules/parse5/lib/sax/index.js
Danny McCormick 39c08a0eaa Initial pass
2019-06-26 21:12:00 -04:00

119 lines
3.6 KiB
JavaScript

'use strict';
var TransformStream = require('stream').Transform,
DevNullStream = require('./dev_null_stream'),
inherits = require('util').inherits,
Tokenizer = require('../tokenizer'),
LocationInfoTokenizerMixin = require('../extensions/location_info/tokenizer_mixin'),
ParserFeedbackSimulator = require('./parser_feedback_simulator'),
mergeOptions = require('../utils/merge_options');
var DEFAULT_OPTIONS = {
locationInfo: false
};
var SAXParser = module.exports = function (options) {
TransformStream.call(this);
this.options = mergeOptions(DEFAULT_OPTIONS, options);
this.tokenizer = new Tokenizer(options);
if (this.options.locationInfo)
new LocationInfoTokenizerMixin(this.tokenizer);
this.parserFeedbackSimulator = new ParserFeedbackSimulator(this.tokenizer);
this.pendingText = null;
this.currentTokenLocation = void 0;
this.lastChunkWritten = false;
this.stopped = false;
// NOTE: always pipe stream to the /dev/null stream to avoid
// `highWaterMark` hit even if we don't have consumers.
// (see: https://github.com/inikulin/parse5/issues/97#issuecomment-171940774)
this.pipe(new DevNullStream());
};
inherits(SAXParser, TransformStream);
//TransformStream implementation
SAXParser.prototype._transform = function (chunk, encoding, callback) {
if (!this.stopped) {
this.tokenizer.write(chunk.toString('utf8'), this.lastChunkWritten);
this._runParsingLoop();
}
this.push(chunk);
callback();
};
SAXParser.prototype._flush = function (callback) {
callback();
};
SAXParser.prototype.end = function (chunk, encoding, callback) {
this.lastChunkWritten = true;
TransformStream.prototype.end.call(this, chunk, encoding, callback);
};
SAXParser.prototype.stop = function () {
this.stopped = true;
};
//Internals
SAXParser.prototype._runParsingLoop = function () {
do {
var token = this.parserFeedbackSimulator.getNextToken();
if (token.type === Tokenizer.HIBERNATION_TOKEN)
break;
if (token.type === Tokenizer.CHARACTER_TOKEN ||
token.type === Tokenizer.WHITESPACE_CHARACTER_TOKEN ||
token.type === Tokenizer.NULL_CHARACTER_TOKEN) {
if (this.options.locationInfo) {
if (this.pendingText === null)
this.currentTokenLocation = token.location;
else
this.currentTokenLocation.endOffset = token.location.endOffset;
}
this.pendingText = (this.pendingText || '') + token.chars;
}
else {
this._emitPendingText();
this._handleToken(token);
}
} while (!this.stopped && token.type !== Tokenizer.EOF_TOKEN);
};
SAXParser.prototype._handleToken = function (token) {
if (this.options.locationInfo)
this.currentTokenLocation = token.location;
if (token.type === Tokenizer.START_TAG_TOKEN)
this.emit('startTag', token.tagName, token.attrs, token.selfClosing, this.currentTokenLocation);
else if (token.type === Tokenizer.END_TAG_TOKEN)
this.emit('endTag', token.tagName, this.currentTokenLocation);
else if (token.type === Tokenizer.COMMENT_TOKEN)
this.emit('comment', token.data, this.currentTokenLocation);
else if (token.type === Tokenizer.DOCTYPE_TOKEN)
this.emit('doctype', token.name, token.publicId, token.systemId, this.currentTokenLocation);
};
SAXParser.prototype._emitPendingText = function () {
if (this.pendingText !== null) {
this.emit('text', this.pendingText, this.currentTokenLocation);
this.pendingText = null;
}
};