invalid XML element names

[punund]

Invalid XML is easily generated from unsanitized arbitrary objects:

xmlbuilder.create('root').ele({'my name': 'John'})

This will produce bad XML <my name>John</my name>. Maybe some escaping or sanitizing scheme should be implemented? ("my name" -> "my_name" or similar).

[oozcitak]

Instead of fixing this on a case by case basis, I believe it will be better in the long-run if we switched to a DOM implementation like jsdom. This will require a major rewrite though, so expect this in a future major release.

[Simran-B]

With stringify: { eleName: fn } it's possible to sanitize names:

const xmlbuilder = require("xmlbuilder")

const nameStartCharRegex = /^[:A-Z_a-z\xC0-\xD6\xD8-\xF6\xF8-\u02FF\u0370-\u037D\u037F-\u1FFF\u200C\u200D\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD]|[\uD800-\uDB7F][\uDC00-\uDFFF]$/
const nameCharRegex = /^[\x2D\.0-:A-Z_a-z\xB7\xC0-\xD6\xD8-\xF6\xF8-\u037D\u037F-\u1FFF\u200C\u200D\u203F\u2040\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD]|[\uD800-\uDB7F][\uDC00-\uDFFF]$/

const sanitizeName = function(name) {
    const oldName = String(name)
    if (oldName.length == 0) {
        return "__unnamed__"
    }
    const newName = []
    if (nameStartCharRegex.test(name[0])) {
        newName.push(name[0])
    } else {
        newName.push("_")
        // might be a valid char except in first position
        if (nameCharRegex.test(name[0])) {
            newName.push(name[0])
        }
    }
    for (i = 1; i < name.length; i++) {
        if (nameCharRegex.test(name[i])) {
            newName.push(name[i])
        } else {
            newName.push("_")
        }
    }
    return newName.join("")
}

let xml = xmlbuilder.create("root", {
    encoding: "UTF-8",
    stringify: {
        eleName: sanitizeName
    }
})

Note: I only tested the regexes briefly, but can not verify their correctness. Create with regenerate:

const regenerate = require("regenerate")

const nameStartChar = regenerate()
    .add(":", "_")
    .addRange("A", "Z")
    .addRange("a", "z")
    .addRange(0xC0, 0xD6)
    .addRange(0xD8, 0xF6)
    .addRange(0xF8, 0x2FF)
    .addRange(0x370, 0x37D)
    .addRange(0x37F, 0x1FFF)
    .addRange(0x200C, 0x200D)
    .addRange(0x2070, 0x218F)
    .addRange(0x2C00, 0x2FEF)
    .addRange(0x3001, 0xD7FF)
    .addRange(0xF900, 0xFDCF)
    .addRange(0xFDF0, 0xFFFD)
    .addRange(0x10000, 0xEFFFF)

const nameChar = regenerate()
    .add(nameStartChar)
    .add("-", ".", 0xB7)
    .addRange("0", "9")
    .addRange(0x0300, 0x036F)
    .addRange(0x203F, 0x2040)

Specs: https://www.w3.org/TR/xml/#sec-common-syn