tupali_fork/milfs/js/ie-emulation-modes-warning.js

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2016-10-29 15:07:15 +00:00
// NOTICE!! DO NOT USE ANY OF THIS JAVASCRIPT
// IT'S JUST JUNK FOR OUR DOCS!
// ++++++++++++++++++++++++++++++++++++++++++
/*!
* Copyright 2014-2015 Twitter, Inc.
*
* Licensed under the Creative Commons Attribution 3.0 Unported License. For
* details, see https://creativecommons.org/licenses/by/3.0/.
*/
// Intended to prevent false-positive bug reports about Bootstrap not working properly in old versions of IE due to folks testing using IE's unreliable emulation modes.
(function () {
'use strict';
function emulatedIEMajorVersion() {
var groups = /MSIE ([0-9.]+)/.exec(window.navigator.userAgent)
if (groups === null) {
return null
}
var ieVersionNum = parseInt(groups[1], 10)
var ieMajorVersion = Math.floor(ieVersionNum)
return ieMajorVersion
}
function actualNonEmulatedIEMajorVersion() {
// Detects the actual version of IE in use, even if it's in an older-IE emulation mode.
// IE JavaScript conditional compilation docs: https://msdn.microsoft.com/library/121hztk3%28v=vs.94%29.aspx
// @cc_on docs: https://msdn.microsoft.com/library/8ka90k2e%28v=vs.94%29.aspx
var jscriptVersion = new Function('/*@cc_on return @_jscript_version; @*/')() // jshint ignore:line
if (jscriptVersion === undefined) {
return 11 // IE11+ not in emulation mode
}
if (jscriptVersion < 9) {
return 8 // IE8 (or lower; haven't tested on IE<8)
}
return jscriptVersion // IE9 or IE10 in any mode, or IE11 in non-IE11 mode
}
var ua = window.navigator.userAgent
if (ua.indexOf('Opera') > -1 || ua.indexOf('Presto') > -1) {
return // Opera, which might pretend to be IE
}
var emulated = emulatedIEMajorVersion()
if (emulated === null) {
return // Not IE
}
var nonEmulated = actualNonEmulatedIEMajorVersion()
if (emulated !== nonEmulated) {
window.alert('WARNING: You appear to be using IE' + nonEmulated + ' in IE' + emulated + ' emulation mode.\nIE emulation modes can behave significantly differently from ACTUAL older versions of IE.\nPLEASE DON\'T FILE BOOTSTRAP BUGS based on testing in IE emulation modes!')
}
})();