Pretty Print XML

prettyPrintXml.js

prettyPrintXml = function (xmlString)
{
  /* linearize */
	let result = xmlString.replace(/>\s*</g, "><").trim();
	/* simplify empty tags */
	result = result.replace(/<(\S+)([^>]*)><\/\1>/g, "<$1$2/>");
	/* remove spaces at tag end */
	result = result.replace(/\s+(\/?>)/g, "$1");
	/* remove too many spaces before attributes */
	result	= result.replace(/\s+(\s\S+="\S+")/g, "$1");
	/* split each tag in a single line */
	result = result.replace(/></g, ">\n<");
	let xmlLines = result.split("\n");
	result = "";
	let indent = 0;
	for (let line of xmlLines)
	{
		if (line.startsWith("</"))
		{
			indent -= 1;
		};
		result += "  ".repeat(Math.max(indent, 0)) + line + "\r\n";
		if ((line.startsWith("</") === false) && ((line.endsWith("/>") === false)))
		{
			indent += 1;
		};
	};
	return result;
};