in static/js/popper.js [2393:2457]
function Popper(reference, popper) {
var _this = this;
var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
classCallCheck(this, Popper);
this.scheduleUpdate = function () {
return requestAnimationFrame(_this.update);
};
// make update() debounced, so that it only runs at most once-per-tick
this.update = debounce(this.update.bind(this));
// with {} we create a new object with the options inside it
this.options = _extends({}, Popper.Defaults, options);
// init state
this.state = {
isDestroyed: false,
isCreated: false,
scrollParents: []
};
// get reference and popper elements (allow jQuery wrappers)
this.reference = reference && reference.jquery ? reference[0] : reference;
this.popper = popper && popper.jquery ? popper[0] : popper;
// Deep merge modifiers options
this.options.modifiers = {};
Object.keys(_extends({}, Popper.Defaults.modifiers, options.modifiers)).forEach(function (name) {
_this.options.modifiers[name] = _extends({}, Popper.Defaults.modifiers[name] || {}, options.modifiers ? options.modifiers[name] : {});
});
// Refactoring modifiers' list (Object => Array)
this.modifiers = Object.keys(this.options.modifiers).map(function (name) {
return _extends({
name: name
}, _this.options.modifiers[name]);
})
// sort the modifiers by order
.sort(function (a, b) {
return a.order - b.order;
});
// modifiers have the ability to execute arbitrary code when Popper.js get inited
// such code is executed in the same order of its modifier
// they could add new properties to their options configuration
// BE AWARE: don't add options to `options.modifiers.name` but to `modifierOptions`!
this.modifiers.forEach(function (modifierOptions) {
if (modifierOptions.enabled && isFunction(modifierOptions.onLoad)) {
modifierOptions.onLoad(_this.reference, _this.popper, _this.options, modifierOptions, _this.state);
}
});
// fire the first update to position the popper in the right place
this.update();
var eventsEnabled = this.options.eventsEnabled;
if (eventsEnabled) {
// setup event listeners, they will take care of update the position in specific situations
this.enableEventListeners();
}
this.state.eventsEnabled = eventsEnabled;
}