Serialization special casing of style, script, etc. needs to be namespace-dependent

[domenic]

This escaping:

parse5/packages/parse5/lib/serializer/index.js

Lines 136 to 149 in 9c683e1

	if (
	parentTn === $.STYLE ||
	parentTn === $.SCRIPT ||
	parentTn === $.XMP ||
	parentTn === $.IFRAME ||
	parentTn === $.NOEMBED ||
	parentTn === $.NOFRAMES ||
	parentTn === $.PLAINTEXT ||
	parentTn === $.NOSCRIPT
	) {
	this.html += content;
	} else {
	this.html += Serializer.escapeString(content, false);
	}

is meant to mimic HTML's

If the parent of current node is a style, script, xmp, iframe, noembed, noframes, or plaintext element, or if the parent of current node is a noscript element and scripting is enabled for the node, then append the value of current node's data IDL attribute literally.

However, while HTML is referring specifically to those nodes in the HTML namespace, parse5 does not check the namespace before serializing.

This leads to the following wrong result in jsdom: https://runkit.com/domenicdenicola/6044168f463fb4001a725307 compared to browsers: http://software.hixie.ch/utilities/js/live-dom-viewer/?saved=8981

[domenic]

parse5/packages/parse5/lib/serializer/index.js

Lines 70 to 89 in 9c683e1

	if (
	tn !== $.AREA &&
	tn !== $.BASE &&
	tn !== $.BASEFONT &&
	tn !== $.BGSOUND &&
	tn !== $.BR &&
	tn !== $.COL &&
	tn !== $.EMBED &&
	tn !== $.FRAME &&
	tn !== $.HR &&
	tn !== $.IMG &&
	tn !== $.INPUT &&
	tn !== $.KEYGEN &&
	tn !== $.LINK &&
	tn !== $.META &&
	tn !== $.PARAM &&
	tn !== $.SOURCE &&
	tn !== $.TRACK &&
	tn !== $.WBR
	) {

is similarly suspicious... in general any checks against $.SOMECONSTANT really should be accompanied with a namespace check.

[nfriedly]

This just bit me today: in a <script> tag && is getting changed to &&, which is a syntax error.

[nfriedly]

Actually, looking closer, $.SCRIPT is on that list, so I'm not sure if I'm hitting this or some other issue...

[nfriedly]

Yeah, this is what's causing my issue:

parse5/packages/parse5-html-rewriting-stream/lib/index.js

Lines 79 to 81 in 9c683e1

	emitText({ text }) {
	this.push(escapeString(text, false));
	}

It doesn't even try to check the namespace or parent element there...

I'll file a separate issue.