Named entities produce invalid XML

[leafac]

Describe the bug

Consider the following program

console.log(
  require("xmlbuilder2").convert(
    { example: "<p>Hello World</p>" },
    {
      format: "xml",
      noDoubleEncoding: true,
      prettyPrint: true,
      wellFormed: true,
    }
  )
);

It produces the following XML:

<?xml version="1.0"?>
<example>&lt;p&gt;Hello&nbsp;World&lt;/p&gt;</example>

Despite having used the wellFormed option, the XML is considered invalid by https://www.xmlvalidation.com (and other validators I tried).

The problem is the named entity  .

One recommend solution is to convert named entities into their numerical equivalents, for example, &#160 or   instead of  . Here’s a list of all named entities and their numeric equivalents, and here’s an npm package that seems to provide that list in a more friendly manner (I haven’t tested it).

I think that xmlbuilder2 should do this conversion.

Expected behavior

XML produced by xmlbuilder2 should be valid, particularly when using the wellFormed option.

Version:

• node.js: 13.7.0
• xmlbuilder2: 2.1.0

[leafac]

I found this other package that seems to be the most used for working with HTML entities: https://github.com/mathiasbynens/he