wasm-metering/demo/node_modules/nanohtml/lib/browser.js

injects metering into webassembly binaries

var hyperx = require('hyperx')
var appendChild = require('./append-child')
var SVG_TAGS = require('./svg-tags')
var BOOL_PROPS = require('./bool-props')

var SVGNS = 'http://www.w3.org/2000/svg'
var XLINKNS = 'http://www.w3.org/1999/xlink'

var COMMENT_TAG = '!--'

function nanoHtmlCreateElement (tag, props, children) {
  var el

  // If an svg tag, it needs a namespace
  if (SVG_TAGS.indexOf(tag) !== -1) {
    props.namespace = SVGNS
  }

  // If we are using a namespace
  var ns = false
  if (props.namespace) {
    ns = props.namespace
    delete props.namespace
  }

  // Create the element
  if (ns) {
    el = document.createElementNS(ns, tag)
  } else if (tag === COMMENT_TAG) {
    return document.createComment(props.comment)
  } else {
    el = document.createElement(tag)
  }

  // Create the properties
  for (var p in props) {
    if (props.hasOwnProperty(p)) {
      var key = p.toLowerCase()
      var val = props[p]
      // Normalize className
      if (key === 'classname') {
        key = 'class'
        p = 'class'
      }
      // The for attribute gets transformed to htmlFor, but we just set as for
      if (p === 'htmlFor') {
        p = 'for'
      }
      // If a property is boolean, set itself to the key
      if (BOOL_PROPS.indexOf(key) !== -1) {
        if (val === 'true') val = key
        else if (val === 'false') continue
      }
      // If a property prefers being set directly vs setAttribute
      if (key.slice(0, 2) === 'on') {
        el[p] = val
      } else {
        if (ns) {
          if (p === 'xlink:href') {
            el.setAttributeNS(XLINKNS, p, val)
          } else if (/^xmlns($|:)/i.test(p)) {
            // skip xmlns definitions
          } else {
            el.setAttributeNS(null, p, val)
          }
        } else {
          el.setAttribute(p, val)
        }
      }
    }
  }

  appendChild(el, children)
  return el
}

module.exports = hyperx(nanoHtmlCreateElement, {comments: true})
module.exports.default = module.exports
module.exports.createElement = nanoHtmlCreateElement