jquintozamora / polyfill-io-feature-detection Goto Github PK

Hi. I'm trying to use this package for loading Intl polyfill. For correct work, it needs also Intl.~locale.[locale] to be loaded. But if I try to add any locale to features I get the next message:

Feature Intl.~locale.en-US can not be detected because it has not JavaScript API.

What if instead of skipping features with ~ this tool will include them in the query string for polyfill.io if the root feature (like Intl for Intl.~locale.en-US) is not supported by the browser?

Hi,

You have a 'let' keyword in index.js. So when using uglify, there is an exception.
Could you modify it to var?

Antony

For the sake of supporting polyfill.io fully, you may want to support IE7 & IE8 in the code base. Two things are needed :

• Not using unsupported features in the codebase itself
• More robust loadScript

Features

Features impacted (as I could tell):

• Array.prototype.filter
• Array.prototype.map
• String.prototype.lastIndexOf
  All of these features are provided by polyfill.io, for IE7 & IE8

Solutions:

• Inline polyfill each of these (just like contains)
• try-catch approach, loading all features if detectBrowserUnsupportedFeatures couldn't even run

loadScript

Proposed version that supports old IE:

function loadScript(src, done) {
    var finished = false

    function handleLoad () {
      if (!finished) {
        finished = true
        done(src)
      }
    }
  
    function handleReadyStateChange () {
      if (!finished) {
        if (script.readyState === 'complete') {
          handleLoad()
        }
      }
    }
  
    function handleError () {
      if (!finished) {
        finished = true
        done(new Error('Failed to load script ' + src))
      }
    }
    var script = document.createElement('script')
    script.onload = handleLoad
    script.type = 'text/javascript'
    script.onreadystatechange = handleReadyStateChange
    script.onerror = handleError
    script.src = src
    document.head.appendChild(script)
}