Function $SnifferProvider

test/angular/1.7/angular.js:21109–21173

* !!! This is an undocumented "private" service !!! * * @name $sniffer * @requires $window * @requires $document * @this * * @property {boolean} history Does the browser support html5 history api ? * @property {boolean} transitions Does the browser support CSS transition events ? * @propert

()

 * This is very simple implementation of testing browser's features.
 */
function $SnifferProvider() {
  this.$get = ['$window', '$document', function($window, $document) {
    var eventSupport = {},
        // Chrome Packaged Apps are not allowed to access `history.pushState`.
        // If not sandboxed, they can be detected by the presence of `chrome.app.runtime`
        // (see https://developer.chrome.com/apps/api_index). If sandboxed, they can be detected by
        // the presence of an extension runtime ID and the absence of other Chrome runtime APIs
        // (see https://developer.chrome.com/apps/manifest/sandbox).
        // (NW.js apps have access to Chrome APIs, but do support `history`.)
        isNw = $window.nw && $window.nw.process,
        isChromePackagedApp =
            !isNw &&
            $window.chrome &&
            ($window.chrome.app && $window.chrome.app.runtime ||
                !$window.chrome.app && $window.chrome.runtime && $window.chrome.runtime.id),
        hasHistoryPushState = !isChromePackagedApp && $window.history && $window.history.pushState,
        android =
          toInt((/android (\d+)/.exec(lowercase(($window.navigator || {}).userAgent)) || [])[1]),
        boxee = /Boxee/i.test(($window.navigator || {}).userAgent),
        document = $document[0] || {},
        bodyStyle = document.body && document.body.style,
        transitions = false,
        animations = false;

    if (bodyStyle) {
      // Support: Android <5, Blackberry Browser 10, default Chrome in Android 4.4.x
      // Mentioned browsers need a -webkit- prefix for transitions & animations.
      transitions = !!('transition' in bodyStyle || 'webkitTransition' in bodyStyle);
      animations = !!('animation' in bodyStyle || 'webkitAnimation' in bodyStyle);
    }


    return {
      // Android has history.pushState, but it does not update location correctly
      // so let's not use the history API at all.
      // http://code.google.com/p/android/issues/detail?id=17471
      // https://github.com/angular/angular.js/issues/904

      // older webkit browser (533.9) on Boxee box has exactly the same problem as Android has
      // so let's not use the history API also
      // We are purposefully using `!(android < 4)` to cover the case when `android` is undefined
      history: !!(hasHistoryPushState && !(android < 4) && !boxee),
      hasEvent: function(event) {
        // Support: IE 9-11 only
        // IE9 implements 'input' event it's so fubared that we rather pretend that it doesn't have
        // it. In particular the event is not fired when backspace or delete key are pressed or
        // when cut operation is performed.
        // IE10+ implements 'input' event but it erroneously fires under various situations,
        // e.g. when placeholder changes, or a form is focused.
        if (event === 'input' && msie) return false;

        if (isUndefined(eventSupport[event])) {
          var divElm = document.createElement('div');
          eventSupport[event] = 'on' + event in divElm;
        }

        return eventSupport[event];
      },