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@popperjs/core/dist/umd/popper.js

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1/**
* @popperjs/core v2.0.6 - MIT License
*/
4
5(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
typeof define === 'function' && define.amd ? define(['exports'], factory) :
(global = global || self, factory(global.Popper = {}));
9}(this, (function (exports) { 'use strict';
10
function getBoundingClientRect(element) {
  var rect = element.getBoundingClientRect();
  return {
    width: rect.width,
    height: rect.height,
    top: rect.top,
    right: rect.right,
    bottom: rect.bottom,
    left: rect.left,
    x: rect.left,
    y: rect.top
  };
}
24
/*:: import type { Window } from '../types'; */
26
/*:: declare function getWindow(node: Node | Window): Window; */
function getWindow(node) {
  if (node.toString() !== '[object Window]') {
    var ownerDocument = node.ownerDocument;
    return ownerDocument ? ownerDocument.defaultView : window;
  }
33
  return node;
}
36
function getWindowScroll(node) {
  var win = getWindow(node);
  var scrollLeft = win.pageXOffset;
  var scrollTop = win.pageYOffset;
  return {
    scrollLeft: scrollLeft,
    scrollTop: scrollTop
  };
}
46
/*:: declare function isElement(node: mixed): boolean %checks(node instanceof
  Element); */
49
function isElement(node) {
  var OwnElement = getWindow(node).Element;
  return node instanceof OwnElement;
}
/*:: declare function isHTMLElement(node: mixed): boolean %checks(node instanceof
  HTMLElement); */
56
57
function isHTMLElement(node) {
  var OwnElement = getWindow(node).HTMLElement;
  return node instanceof OwnElement;
}
62
function getHTMLElementScroll(element) {
  return {
    scrollLeft: element.scrollLeft,
    scrollTop: element.scrollTop
  };
}
69
function getNodeScroll(node) {
  if (node === getWindow(node) || !isHTMLElement(node)) {
    return getWindowScroll(node);
  } else {
    return getHTMLElementScroll(node);
  }
}
77
function getNodeName(element) {
  return element ? (element.nodeName || '').toLowerCase() : null;
}
81
function getDocumentElement(element) {
  // $FlowFixMe: assume body is always available
  return (isElement(element) ? element.ownerDocument : element.document).documentElement;
}
86
function getWindowScrollBarX(element) {
  // If <html> has a CSS width greater than the viewport, then this will be
  // incorrect for RTL.
  // Popper 1 is broken in this case and never had a bug report so let's assume
  // it's not an issue. I don't think anyone ever specifies width on <html>
  // anyway.
  // Browsers where the left scrollbar doesn't cause an issue report `0` for
  // this (e.g. Edge 2019, IE11, Safari)
  return getBoundingClientRect(getDocumentElement(element)).left + getWindowScroll(element).scrollLeft;
}
97
// Composite means it takes into account transforms as well as layout.
99
function getCompositeRect(elementOrVirtualElement, offsetParent, isFixed) {
  if (isFixed === void 0) {
    isFixed = false;
  }
104
  var documentElement;
  var rect = getBoundingClientRect(elementOrVirtualElement);
  var scroll = {
    scrollLeft: 0,
    scrollTop: 0
  };
  var offsets = {
    x: 0,
    y: 0
  };
115
  if (!isFixed) {
    if (getNodeName(offsetParent) !== 'body') {
      scroll = getNodeScroll(offsetParent);
    }
120
    if (isHTMLElement(offsetParent)) {
      offsets = getBoundingClientRect(offsetParent);
      offsets.x += offsetParent.clientLeft;
      offsets.y += offsetParent.clientTop;
    } else if (documentElement = getDocumentElement(offsetParent)) {
      offsets.x = getWindowScrollBarX(documentElement);
    }
  }
129
  return {
    x: rect.left + scroll.scrollLeft - offsets.x,
    y: rect.top + scroll.scrollTop - offsets.y,
    width: rect.width,
    height: rect.height
  };
}
137
// Returns the layout rect of an element relative to its offsetParent. Layout
// means it doesn't take into account transforms.
function getLayoutRect(element) {
  return {
    x: element.offsetLeft,
    y: element.offsetTop,
    width: element.offsetWidth,
    height: element.offsetHeight
  };
}
148
function getParentNode(element) {
  if (getNodeName(element) === 'html') {
    return element;
  }
153
  return element.parentNode || // DOM Element detected
  // $FlowFixMe: need a better way to handle this...
  element.host || // ShadowRoot detected
  document.ownerDocument || // Fallback to ownerDocument if available
  document.documentElement // Or to documentElement if everything else fails
  ;
}
161
function getComputedStyle(element) {
  return getWindow(element).getComputedStyle(element);
}
165
function getScrollParent(node) {
  if (['html', 'body', '#document'].indexOf(getNodeName(node)) >= 0) {
    // $FlowFixMe: assume body is always available
    return node.ownerDocument.body;
  }
171
  if (isHTMLElement(node)) {
    // Firefox wants us to check `-x` and `-y` variations as well
    var _getComputedStyle = getComputedStyle(node),
        overflow = _getComputedStyle.overflow,
        overflowX = _getComputedStyle.overflowX,
        overflowY = _getComputedStyle.overflowY;
178
    if (/auto|scroll|overlay|hidden/.test(overflow + overflowY + overflowX)) {
      return node;
    }
  }
183
  return getScrollParent(getParentNode(node));
}
186
function listScrollParents(element, list) {
  if (list === void 0) {
    list = [];
  }
191
  var scrollParent = getScrollParent(element);
  var isBody = getNodeName(scrollParent) === 'body';
  var target = isBody ? getWindow(scrollParent) : scrollParent;
  var updatedList = list.concat(target);
  return isBody ? updatedList : // $FlowFixMe: isBody tells us target will be an HTMLElement here
  updatedList.concat(listScrollParents(getParentNode(target)));
}
199
function isTableElement(element) {
  return ['table', 'td', 'th'].indexOf(getNodeName(element)) >= 0;
}
203
var isFirefox = function isFirefox() {
  return typeof window.InstallTrigger !== 'undefined';
};
207
function getTrueOffsetParent(element) {
  var offsetParent;
210
  if (!isHTMLElement(element) || !(offsetParent = element.offsetParent) || // https://github.com/popperjs/popper-core/issues/837
  isFirefox() && getComputedStyle(offsetParent).position === 'fixed') {
    return null;
  }
215
  return offsetParent;
}
218
function getOffsetParent(element) {
  var window = getWindow(element);
  var offsetParent = getTrueOffsetParent(element); // Find the nearest non-table offsetParent
222
  while (offsetParent && isTableElement(offsetParent)) {
    offsetParent = getTrueOffsetParent(offsetParent);
  }
226
  if (offsetParent && getNodeName(offsetParent) === 'body' && getComputedStyle(offsetParent).position === 'static') {
    return window;
  }
230
  return offsetParent || window;
}
233
var top = 'top';
var bottom = 'bottom';
var right = 'right';
var left = 'left';
var auto = 'auto';
var basePlacements = [top, bottom, right, left];
var start = 'start';
var end = 'end';
var clippingParents = 'clippingParents';
var viewport = 'viewport';
var popper = 'popper';
var reference = 'reference';
var variationPlacements =
/*#__PURE__*/
basePlacements.reduce(function (acc, placement) {
  return acc.concat([placement + "-" + start, placement + "-" + end]);
}, []);
var placements =
/*#__PURE__*/
[].concat(basePlacements, [auto]).reduce(function (acc, placement) {
  return acc.concat([placement, placement + "-" + start, placement + "-" + end]);
}, []); // modifiers that need to read the DOM
256
var beforeRead = 'beforeRead';
var read = 'read';
var afterRead = 'afterRead'; // pure-logic modifiers
260
var beforeMain = 'beforeMain';
var main = 'main';
var afterMain = 'afterMain'; // modifier with the purpose to write to the DOM (or write into a framework state)
264
var beforeWrite = 'beforeWrite';
var write = 'write';
var afterWrite = 'afterWrite';
var modifierPhases = [beforeRead, read, afterRead, beforeMain, main, afterMain, beforeWrite, write, afterWrite];
269
function order(modifiers) {
  var map = new Map();
  var visited = new Set();
  var result = [];
  modifiers.forEach(function (modifier) {
    map.set(modifier.name, modifier);
  }); // On visiting object, check for its dependencies and visit them recursively
277
  function sort(modifier) {
    visited.add(modifier.name);
    var requires = [].concat(modifier.requires || [], modifier.requiresIfExists || []);
    requires.forEach(function (dep) {
      if (!visited.has(dep)) {
        var depModifier = map.get(dep);
284
        if (depModifier) {
          sort(depModifier);
        }
      }
    });
    result.push(modifier);
  }
292
  modifiers.forEach(function (modifier) {
    if (!visited.has(modifier.name)) {
      // check for visited object
      sort(modifier);
    }
  });
  return result;
}
301
function orderModifiers(modifiers) {
  // order based on dependencies
  var orderedModifiers = order(modifiers); // order based on phase
305
  return modifierPhases.reduce(function (acc, phase) {
    return acc.concat(orderedModifiers.filter(function (modifier) {
      return modifier.phase === phase;
    }));
  }, []);
}
312
function debounce(fn) {
  var pending;
  return function () {
    if (!pending) {
      pending = new Promise(function (resolve) {
        Promise.resolve().then(function () {
          pending = undefined;
          resolve(fn());
        });
      });
    }
324
    return pending;
  };
}
328
function format(str) {
  for (var _len = arguments.length, args = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
    args[_key - 1] = arguments[_key];
  }
333
  return [].concat(args).reduce(function (p, c) {
    return p.replace(/%s/, c);
  }, str);
}
338
var INVALID_MODIFIER_ERROR = 'Popper: modifier "%s" provided an invalid %s property, expected %s but got %s';
var MISSING_DEPENDENCY_ERROR = 'Popper: modifier "%s" requires "%s", but "%s" modifier is not available';
var VALID_PROPERTIES = ['name', 'enabled', 'phase', 'fn', 'effect', 'requires', 'options'];
function validateModifiers(modifiers) {
  modifiers.forEach(function (modifier) {
    Object.keys(modifier).forEach(function (key) {
      switch (key) {
        case 'name':
          if (typeof modifier.name !== 'string') {
            console.error(format(INVALID_MODIFIER_ERROR, String(modifier.name), '"name"', '"string"', "\"" + String(modifier.name) + "\""));
          }
350
          break;
352
        case 'enabled':
          if (typeof modifier.enabled !== 'boolean') {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"enabled"', '"boolean"', "\"" + String(modifier.enabled) + "\""));
          }
357
        case 'phase':
          if (modifierPhases.indexOf(modifier.phase) < 0) {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"phase"', "either " + modifierPhases.join(', '), "\"" + String(modifier.phase) + "\""));
          }
362
          break;
364
        case 'fn':
          if (typeof modifier.fn !== 'function') {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"fn"', '"function"', "\"" + String(modifier.fn) + "\""));
          }
369
          break;
371
        case 'effect':
          if (typeof modifier.effect !== 'function') {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"effect"', '"function"', "\"" + String(modifier.fn) + "\""));
          }
376
          break;
378
        case 'requires':
          if (!Array.isArray(modifier.requires)) {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"requires"', '"array"', "\"" + String(modifier.requires) + "\""));
          }
383
          break;
385
        case 'requiresIfExists':
          if (!Array.isArray(modifier.requiresIfExists)) {
            console.error(format(INVALID_MODIFIER_ERROR, modifier.name, '"requiresIfExists"', '"array"', "\"" + String(modifier.requiresIfExists) + "\""));
          }
390
          break;
392
        case 'options':
        case 'data':
          break;
396
        default:
          console.error("PopperJS: an invalid property has been provided to the \"" + modifier.name + "\" modifier, valid properties are " + VALID_PROPERTIES.map(function (s) {
            return "\"" + s + "\"";
          }).join(', ') + "; but \"" + key + "\" was provided.");
      }
402
      modifier.requires && modifier.requires.forEach(function (requirement) {
        if (modifiers.find(function (mod) {
          return mod.name === requirement;
        }) == null) {
          console.error(format(MISSING_DEPENDENCY_ERROR, String(modifier.name), requirement, requirement));
        }
      });
    });
  });
}
413
function uniqueBy(arr, fn) {
  var identifiers = new Set();
  return arr.filter(function (item) {
    var identifier = fn(item);
418
    if (!identifiers.has(identifier)) {
      identifiers.add(identifier);
      return true;
    }
  });
}
425
function getBasePlacement(placement) {
  return placement.split('-')[0];
}
429
function mergeByName(modifiers) {
  var merged = modifiers.reduce(function (merged, current) {
    var existing = merged[current.name];
    merged[current.name] = existing ? Object.assign({}, existing, {}, current, {
      options: Object.assign({}, existing.options, {}, current.options),
      data: Object.assign({}, existing.data, {}, current.data)
    }) : current;
    return merged;
  }, {}); // IE11 does not support Object.values
439
  return Object.keys(merged).map(function (key) {
    return merged[key];
  });
}
444
var INVALID_ELEMENT_ERROR = 'Popper: Invalid reference or popper argument provided. They must be either a DOM element or virtual element.';
var INFINITE_LOOP_ERROR = 'Popper: An infinite loop in the modifiers cycle has been detected! The cycle has been interrupted to prevent a browser crash.';
var DEFAULT_OPTIONS = {
  placement: 'bottom',
  modifiers: [],
  strategy: 'absolute'
};
452
function areValidElements() {
  for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
    args[_key] = arguments[_key];
  }
457
  return !args.some(function (element) {
    return !(element && typeof element.getBoundingClientRect === 'function');
  });
}
462
function popperGenerator(generatorOptions) {
  if (generatorOptions === void 0) {
    generatorOptions = {};
  }
467
  var _generatorOptions = generatorOptions,
      _generatorOptions$def = _generatorOptions.defaultModifiers,
      defaultModifiers = _generatorOptions$def === void 0 ? [] : _generatorOptions$def,
      _generatorOptions$def2 = _generatorOptions.defaultOptions,
      defaultOptions = _generatorOptions$def2 === void 0 ? DEFAULT_OPTIONS : _generatorOptions$def2;
  return function createPopper(reference, popper, options) {
    if (options === void 0) {
      options = defaultOptions;
    }
477
    var state = {
      placement: 'bottom',
      orderedModifiers: [],
      options: Object.assign({}, DEFAULT_OPTIONS, {}, defaultOptions),
      modifiersData: {},
      elements: {
        reference: reference,
        popper: popper
      },
      attributes: {},
      styles: {}
    };
    var effectCleanupFns = [];
    var isDestroyed = false;
    var instance = {
      state: state,
      setOptions: function setOptions(options) {
        cleanupModifierEffects();
        state.options = Object.assign({}, defaultOptions, {}, state.options, {}, options);
        state.scrollParents = {
          reference: isElement(reference) ? listScrollParents(reference) : [],
          popper: listScrollParents(popper)
        }; // Orders the modifiers based on their dependencies and `phase`
        // properties
502
        var orderedModifiers = orderModifiers(mergeByName([].concat(defaultModifiers, state.options.modifiers))); // Strip out disabled modifiers
504
        state.orderedModifiers = orderedModifiers.filter(function (m) {
          return m.enabled;
        }); // Validate the provided modifiers so that the consumer will get warned
        // if one of the modifiers is invalid for any reason
509
        {
          var modifiers = uniqueBy([].concat(orderedModifiers, state.options.modifiers), function (_ref) {
            var name = _ref.name;
            return name;
          });
          validateModifiers(modifiers);
516
          if (getBasePlacement(state.options.placement) === auto) {
            var flipModifier = state.orderedModifiers.find(function (_ref2) {
              var name = _ref2.name;
              return name === 'flip';
            });
522
            if (!flipModifier) {
              console.error(['Popper: "auto" placements require the "flip" modifier be', 'present and enabled to work.'].join(' '));
            }
          }
527
          var _getComputedStyle = getComputedStyle(popper),
              marginTop = _getComputedStyle.marginTop,
              marginRight = _getComputedStyle.marginRight,
              marginBottom = _getComputedStyle.marginBottom,
              marginLeft = _getComputedStyle.marginLeft; // We no longer take into account `margins` on the popper, and it can
          // cause bugs with positioning, so we'll warn the consumer
534
535
          if ([marginTop, marginRight, marginBottom, marginLeft].some(function (margin) {
            return parseFloat(margin);
          })) {
            console.warn(['Popper: CSS "margin" styles cannot be used to apply padding', 'between the popper and its reference element or boundary.', 'To replicate margin, use the `offset` modifier, as well as', 'the `padding` option in the `preventOverflow` and `flip`', 'modifiers.'].join(' '));
          }
        }
542
        runModifierEffects();
        return instance.update();
      },
      // Sync update – it will always be executed, even if not necessary. This
      // is useful for low frequency updates where sync behavior simplifies the
      // logic.
      // For high frequency updates (e.g. `resize` and `scroll` events), always
      // prefer the async Popper#update method
      forceUpdate: function forceUpdate() {
        if (isDestroyed) {
          return;
        }
555
        var _state$elements = state.elements,
            reference = _state$elements.reference,
            popper = _state$elements.popper; // Don't proceed if `reference` or `popper` are not valid elements
        // anymore
560
        if (!areValidElements(reference, popper)) {
          {
            console.error(INVALID_ELEMENT_ERROR);
          }
565
          return;
        } // Store the reference and popper rects to be read by modifiers
568
569
        state.rects = {
          reference: getCompositeRect(reference, getOffsetParent(popper), state.options.strategy === 'fixed'),
          popper: getLayoutRect(popper)
        }; // Modifiers have the ability to reset the current update cycle. The
        // most common use case for this is the `flip` modifier changing the
        // placement, which then needs to re-run all the modifiers, because the
        // logic was previously ran for the previous placement and is therefore
        // stale/incorrect
578
        state.reset = false;
        state.placement = state.options.placement; // On each update cycle, the `modifiersData` property for each modifier
        // is filled with the initial data specified by the modifier. This means
        // it doesn't persist and is fresh on each update.
        // To ensure persistent data, use `${name}#persistent`
584
        state.orderedModifiers.forEach(function (modifier) {
          return state.modifiersData[modifier.name] = Object.assign({}, modifier.data);
        });
        var __debug_loops__ = 0;
589
        for (var index = 0; index < state.orderedModifiers.length; index++) {
          {
            __debug_loops__ += 1;
593
            if (__debug_loops__ > 100) {
              console.error(INFINITE_LOOP_ERROR);
              break;
            }
          }
599
          if (state.reset === true) {
            state.reset = false;
            index = -1;
            continue;
          }
605
          var _state$orderedModifie = state.orderedModifiers[index],
              fn = _state$orderedModifie.fn,
              _state$orderedModifie2 = _state$orderedModifie.options,
              _options = _state$orderedModifie2 === void 0 ? {} : _state$orderedModifie2,
              name = _state$orderedModifie.name;
611
          if (typeof fn === 'function') {
            state = fn({
              state: state,
              options: _options,
              name: name,
              instance: instance
            }) || state;
          }
        }
      },
      // Async and optimistically optimized update – it will not be executed if
      // not necessary (debounced to run at most once-per-tick)
      update: debounce(function () {
        return new Promise(function (resolve) {
          instance.forceUpdate();
          resolve(state);
        });
      }),
      destroy: function destroy() {
        cleanupModifierEffects();
        isDestroyed = true;
      }
    };
635
    if (!areValidElements(reference, popper)) {
      {
        console.error(INVALID_ELEMENT_ERROR);
      }
640
      return instance;
    }
643
    instance.setOptions(options).then(function (state) {
      if (!isDestroyed && options.onFirstUpdate) {
        options.onFirstUpdate(state);
      }
    }); // Modifiers have the ability to execute arbitrary code before the first
    // update cycle runs. They will be executed in the same order as the update
    // cycle. This is useful when a modifier adds some persistent data that
    // other modifiers need to use, but the modifier is run after the dependent
    // one.
653
    function runModifierEffects() {
      state.orderedModifiers.forEach(function (_ref3) {
        var name = _ref3.name,
            _ref3$options = _ref3.options,
            options = _ref3$options === void 0 ? {} : _ref3$options,
            effect = _ref3.effect;
660
        if (typeof effect === 'function') {
          var cleanupFn = effect({
            state: state,
            name: name,
            instance: instance,
            options: options
          });
668
          var noopFn = function noopFn() {};
670
          effectCleanupFns.push(cleanupFn || noopFn);
        }
      });
    }
675
    function cleanupModifierEffects() {
      effectCleanupFns.forEach(function (fn) {
        return fn();
      });
      effectCleanupFns = [];
    }
682
    return instance;
  };
}
686
var passive = {
  passive: true
};
690
function effect(_ref) {
  var state = _ref.state,
      instance = _ref.instance,
      options = _ref.options;
  var _options$scroll = options.scroll,
      scroll = _options$scroll === void 0 ? true : _options$scroll,
      _options$resize = options.resize,
      resize = _options$resize === void 0 ? true : _options$resize;
  var window = getWindow(state.elements.popper);
  var scrollParents = [].concat(state.scrollParents.reference, state.scrollParents.popper);
701
  if (scroll) {
    scrollParents.forEach(function (scrollParent) {
      scrollParent.addEventListener('scroll', instance.update, passive);
    });
  }
707
  if (resize) {
    window.addEventListener('resize', instance.update, passive);
  }
711
  return function () {
    if (scroll) {
      scrollParents.forEach(function (scrollParent) {
        scrollParent.removeEventListener('scroll', instance.update, passive);
      });
    }
718
    if (resize) {
      window.removeEventListener('resize', instance.update, passive);
    }
  };
}
724
var eventListeners = {
  name: 'eventListeners',
  enabled: true,
  phase: 'write',
  fn: function fn() {},
  effect: effect,
  data: {}
};
733
function getVariation(placement) {
  return placement.split('-')[1];
}
737
function getMainAxisFromPlacement(placement) {
  return ['top', 'bottom'].indexOf(placement) >= 0 ? 'x' : 'y';
}
741
function computeOffsets(_ref) {
  var reference = _ref.reference,
      element = _ref.element,
      placement = _ref.placement;
  var basePlacement = placement ? getBasePlacement(placement) : null;
  var variation = placement ? getVariation(placement) : null;
  var commonX = reference.x + reference.width / 2 - element.width / 2;
  var commonY = reference.y + reference.height / 2 - element.height / 2;
  var offsets;
751
  switch (basePlacement) {
    case top:
      offsets = {
        x: commonX,
        y: reference.y - element.height
      };
      break;
759
    case bottom:
      offsets = {
        x: commonX,
        y: reference.y + reference.height
      };
      break;
766
    case right:
      offsets = {
        x: reference.x + reference.width,
        y: commonY
      };
      break;
773
    case left:
      offsets = {
        x: reference.x - element.width,
        y: commonY
      };
      break;
780
    default:
      offsets = {
        x: reference.x,
        y: reference.y
      };
  }
787
  var mainAxis = basePlacement ? getMainAxisFromPlacement(basePlacement) : null;
789
  if (mainAxis != null) {
    var len = mainAxis === 'y' ? 'height' : 'width';
792
    switch (variation) {
      case start:
        offsets[mainAxis] = Math.floor(offsets[mainAxis]) - Math.floor(reference[len] / 2 - element[len] / 2);
        break;
797
      case end:
        offsets[mainAxis] = Math.floor(offsets[mainAxis]) + Math.ceil(reference[len] / 2 - element[len] / 2);
        break;
    }
  }
803
  return offsets;
}
806
function popperOffsets(_ref) {
  var state = _ref.state,
      name = _ref.name;
  // Offsets are the actual position the popper needs to have to be
  // properly positioned near its reference element
  // This is the most basic placement, and will be adjusted by
  // the modifiers in the next step
  state.modifiersData[name] = computeOffsets({
    reference: state.rects.reference,
    element: state.rects.popper,
    strategy: 'absolute',
    placement: state.placement
  });
}
821
var popperOffsets$1 = {
  name: 'popperOffsets',
  enabled: true,
  phase: 'read',
  fn: popperOffsets,
  data: {}
};
829
var unsetSides = {
  top: 'auto',
  right: 'auto',
  bottom: 'auto',
  left: 'auto'
}; // Round the offsets to the nearest suitable subpixel based on the DPR.
// Zooming can change the DPR, but it seems to report a value that will
// cleanly divide the values into the appropriate subpixels.
838
function roundOffsets(_ref) {
  var x = _ref.x,
      y = _ref.y;
  var win = window;
  var dpr = win.devicePixelRatio || 1;
  return {
    x: Math.round(x * dpr) / dpr || 0,
    y: Math.round(y * dpr) / dpr || 0
  };
}
849
function mapToStyles(_ref2) {
  var _Object$assign2;
852
  var popper = _ref2.popper,
      popperRect = _ref2.popperRect,
      placement = _ref2.placement,
      offsets = _ref2.offsets,
      position = _ref2.position,
      gpuAcceleration = _ref2.gpuAcceleration,
      adaptive = _ref2.adaptive;
860
  var _roundOffsets = roundOffsets(offsets),
      x = _roundOffsets.x,
      y = _roundOffsets.y;
864
  var hasX = offsets.hasOwnProperty('x');
  var hasY = offsets.hasOwnProperty('y');
  var sideX = left;
  var sideY = top;
  var win = window;
870
  if (adaptive) {
    var offsetParent = getOffsetParent(popper);
873
    if (offsetParent === getWindow(popper)) {
      offsetParent = getDocumentElement(popper);
    } // $FlowFixMe: force type refinement, we compare offsetParent with window above, but Flow doesn't detect it
877
    /*:: offsetParent = (offsetParent: Element); */
879
880
    if (placement === top) {
      sideY = bottom;
      y -= offsetParent.clientHeight - popperRect.height;
      y *= gpuAcceleration ? 1 : -1;
    }
886
    if (placement === left) {
      sideX = right;
      x -= offsetParent.clientWidth - popperRect.width;
      x *= gpuAcceleration ? 1 : -1;
    }
  }
893
  var commonStyles = Object.assign({
    position: position
  }, adaptive && unsetSides);
897
  if (gpuAcceleration) {
    var _Object$assign;
900
    return Object.assign({}, commonStyles, (_Object$assign = {}, _Object$assign[sideY] = hasY ? '0' : '', _Object$assign[sideX] = hasX ? '0' : '', _Object$assign.transform = (win.devicePixelRatio || 1) < 2 ? "translate(" + x + "px, " + y + "px)" : "translate3d(" + x + "px, " + y + "px, 0)", _Object$assign));
  }
903
  return Object.assign({}, commonStyles, (_Object$assign2 = {}, _Object$assign2[sideY] = hasY ? y + "px" : '', _Object$assign2[sideX] = hasX ? x + "px" : '', _Object$assign2.transform = '', _Object$assign2));
}
906
function computeStyles(_ref3) {
  var state = _ref3.state,
      options = _ref3.options;
  var _options$gpuAccelerat = options.gpuAcceleration,
      gpuAcceleration = _options$gpuAccelerat === void 0 ? true : _options$gpuAccelerat,
      _options$adaptive = options.adaptive,
      adaptive = _options$adaptive === void 0 ? true : _options$adaptive;
914
  {
    var _getComputedStyle = getComputedStyle(state.elements.popper),
        transitionProperty = _getComputedStyle.transitionProperty;
918
    if (adaptive && ['transform', 'top', 'right', 'bottom', 'left'].some(function (property) {
      return transitionProperty.indexOf(property) >= 0;
    })) {
      console.warn(['Popper: Detected CSS transitions on at least one of the following', 'CSS properties: "transform", "top", "right", "bottom", "left".', '\n\n', 'Disable the "computeStyles" modifier\'s `adaptive` option to allow', 'for smooth transitions, or remove these properties from the CSS', 'transition declaration on the popper element if only transitioning', 'opacity or background-color for example.', '\n\n', 'We recommend using the popper element as a wrapper around an inner', 'element that can have any CSS property transitioned for animations.'].join(' '));
    }
  }
925
  var commonStyles = {
    placement: getBasePlacement(state.placement),
    popper: state.elements.popper,
    popperRect: state.rects.popper,
    gpuAcceleration: gpuAcceleration
  }; // popper offsets are always available
932
  state.styles.popper = Object.assign({}, state.styles.popper, {}, mapToStyles(Object.assign({}, commonStyles, {
    offsets: state.modifiersData.popperOffsets,
    position: state.options.strategy,
    adaptive: adaptive
  }))); // arrow offsets may not be available
938
  if (state.modifiersData.arrow != null) {
    state.styles.arrow = Object.assign({}, state.styles.arrow, {}, mapToStyles(Object.assign({}, commonStyles, {
      offsets: state.modifiersData.arrow,
      position: 'absolute',
      adaptive: false
    })));
  }
946
  state.attributes.popper = Object.assign({}, state.attributes.popper, {
    'data-popper-placement': state.placement
  });
}
951
var computeStyles$1 = {
  name: 'computeStyles',
  enabled: true,
  phase: 'beforeWrite',
  fn: computeStyles,
  data: {}
};
959
// and applies them to the HTMLElements such as popper and arrow
961
function applyStyles(_ref) {
  var state = _ref.state;
  Object.keys(state.elements).forEach(function (name) {
    var style = state.styles[name] || {};
    var attributes = state.attributes[name] || {};
    var element = state.elements[name]; // arrow is optional + virtual elements
968
    if (!isHTMLElement(element) || !getNodeName(element)) {
      return;
    } // Flow doesn't support to extend this property, but it's the most
    // effective way to apply styles to an HTMLElement
    // $FlowFixMe
974
975
    Object.assign(element.style, style);
    Object.keys(attributes).forEach(function (name) {
      var value = attributes[name];
979
      if (value === false) {
        element.removeAttribute(name);
      } else {
        element.setAttribute(name, value === true ? '' : value);
      }
    });
  });
}
988
function effect$1(_ref2) {
  var state = _ref2.state;
  var initialStyles = {
    popper: {
      position: 'absolute',
      left: '0',
      top: '0',
      margin: '0'
    },
    arrow: {
      position: 'absolute'
    },
    reference: {}
  };
  Object.assign(state.elements.popper.style, initialStyles.popper);
1004
  if (state.elements.arrow) {
    Object.assign(state.elements.arrow.style, initialStyles.arrow);
  }
1008
  return function () {
    Object.keys(state.elements).forEach(function (name) {
      var element = state.elements[name];
      var attributes = state.attributes[name] || {};
      var styleProperties = Object.keys(state.styles.hasOwnProperty(name) ? state.styles[name] : initialStyles[name]); // Set all values to an empty string to unset them
1014
      var style = styleProperties.reduce(function (style, property) {
        style[property] = '';
        return style;
      }, {}); // arrow is optional + virtual elements
1019
      if (!isHTMLElement(element) || !getNodeName(element)) {
        return;
      } // Flow doesn't support to extend this property, but it's the most
      // effective way to apply styles to an HTMLElement
      // $FlowFixMe
1025
1026
      Object.assign(element.style, style);
      Object.keys(attributes).forEach(function (attribute) {
        element.removeAttribute(attribute);
      });
    });
  };
}
1034
var applyStyles$1 = {
  name: 'applyStyles',
  enabled: true,
  phase: 'write',
  fn: applyStyles,
  effect: effect$1,
  requires: ['computeStyles']
};
1043
function distanceAndSkiddingToXY(placement, rects, offset) {
  var basePlacement = getBasePlacement(placement);
  var invertDistance = [left, top].indexOf(basePlacement) >= 0 ? -1 : 1;
1047
  var _ref = typeof offset === 'function' ? offset(Object.assign({}, rects, {
    placement: placement
  })) : offset,
      skidding = _ref[0],
      distance = _ref[1];
1053
  skidding = skidding || 0;
  distance = (distance || 0) * invertDistance;
  return [left, right].indexOf(basePlacement) >= 0 ? {
    x: distance,
    y: skidding
  } : {
    x: skidding,
    y: distance
  };
}
1064
function offset(_ref2) {
  var state = _ref2.state,
      options = _ref2.options,
      name = _ref2.name;
  var _options$offset = options.offset,
      offset = _options$offset === void 0 ? [0, 0] : _options$offset;
  var data = placements.reduce(function (acc, placement) {
    acc[placement] = distanceAndSkiddingToXY(placement, state.rects, offset);
    return acc;
  }, {});
  var _data$state$placement = data[state.placement],
      x = _data$state$placement.x,
      y = _data$state$placement.y;
  state.modifiersData.popperOffsets.x += x;
  state.modifiersData.popperOffsets.y += y;
  state.modifiersData[name] = data;
}
1082
var offset$1 = {
  name: 'offset',
  enabled: true,
  phase: 'main',
  requires: ['popperOffsets'],
  fn: offset
};
1090
var hash = {
  left: 'right',
  right: 'left',
  bottom: 'top',
  top: 'bottom'
};
function getOppositePlacement(placement) {
  return placement.replace(/left|right|bottom|top/g, function (matched) {
    return hash[matched];
  });
}
1102
var hash$1 = {
  start: 'end',
  end: 'start'
};
function getOppositeVariationPlacement(placement) {
  return placement.replace(/start|end/g, function (matched) {
    return hash$1[matched];
  });
}
1112
function getViewportRect(element) {
  var win = getWindow(element);
  return {
    width: win.innerWidth,
    height: win.innerHeight,
    x: 0,
    y: 0
  };
}
1122
function getDocumentRect(element) {
  var win = getWindow(element);
  var winScroll = getWindowScroll(element);
  var documentRect = getCompositeRect(getDocumentElement(element), win);
  documentRect.height = Math.max(documentRect.height, win.innerHeight);
  documentRect.width = Math.max(documentRect.width, win.innerWidth);
  documentRect.x = -winScroll.scrollLeft;
  documentRect.y = -winScroll.scrollTop;
  return documentRect;
}
1133
function toNumber(cssValue) {
  return parseFloat(cssValue) || 0;
}
1137
function getBorders(element) {
  var computedStyle = isHTMLElement(element) ? getComputedStyle(element) : {};
  return {
    top: toNumber(computedStyle.borderTopWidth),
    right: toNumber(computedStyle.borderRightWidth),
    bottom: toNumber(computedStyle.borderBottomWidth),
    left: toNumber(computedStyle.borderLeftWidth)
  };
}
1147
function getDecorations(element) {
  var win = getWindow(element);
  var borders = getBorders(element);
  var isHTML = getNodeName(element) === 'html';
  var winScrollBarX = getWindowScrollBarX(element);
  var x = element.clientWidth + borders.right;
  var y = element.clientHeight + borders.bottom; // HACK:
  // document.documentElement.clientHeight on iOS reports the height of the
  // viewport including the bottom bar, even if the bottom bar isn't visible.
  // If the difference between window innerHeight and html clientHeight is more
  // than 50, we assume it's a mobile bottom bar and ignore scrollbars.
  // * A 50px thick scrollbar is likely non-existent (macOS is 15px and Windows
  //   is about 17px)
  // * The mobile bar is 114px tall
1162
  if (isHTML && win.innerHeight - element.clientHeight > 50) {
    y = win.innerHeight - borders.bottom;
  }
1166
  return {
    top: isHTML ? 0 : element.clientTop,
    right: // RTL scrollbar (scrolling containers only)
    element.clientLeft > borders.left ? borders.right : // LTR scrollbar
    isHTML ? win.innerWidth - x - winScrollBarX : element.offsetWidth - x,
    bottom: isHTML ? win.innerHeight - y : element.offsetHeight - y,
    left: isHTML ? winScrollBarX : element.clientLeft
  };
}
1176
function contains(parent, child) {
  // $FlowFixMe: hasOwnProperty doesn't seem to work in tests
  var isShadow = Boolean(child.getRootNode && child.getRootNode().host); // First, attempt with faster native method
1180
  if (parent.contains(child)) {
    return true;
  } // then fallback to custom implementation with Shadow DOM support
  else if (isShadow) {
      var next = child;
1186
      do {
        if (next && parent.isSameNode(next)) {
          return true;
        } // $FlowFixMe: need a better way to handle this...
1191
1192
        next = next.parentNode || next.host;
      } while (next);
    } // Give up, the result is false
1196
1197
  return false;
}
1200
function rectToClientRect(rect) {
  return Object.assign({}, rect, {
    left: rect.x,
    top: rect.y,
    right: rect.x + rect.width,
    bottom: rect.y + rect.height
  });
}
1209
function getClientRectFromMixedType(element, clippingParent) {
  return clippingParent === viewport ? rectToClientRect(getViewportRect(element)) : isHTMLElement(clippingParent) ? getBoundingClientRect(clippingParent) : rectToClientRect(getDocumentRect(getDocumentElement(element)));
} // A "clipping parent" is an overflowable container with the characteristic of
// clipping (or hiding) overflowing elements with a position different from
// `initial`
1215
1216
function getClippingParents(element) {
  var clippingParents = listScrollParents(element);
  var canEscapeClipping = ['absolute', 'fixed'].indexOf(getComputedStyle(element).position) >= 0;
  var clipperElement = canEscapeClipping && isHTMLElement(element) ? getOffsetParent(element) : element;
1221
  if (!isElement(clipperElement)) {
    return [];
  } // $FlowFixMe: https://github.com/facebook/flow/issues/1414
1225
1226
  return clippingParents.filter(function (clippingParent) {
    return isElement(clippingParent) && contains(clippingParent, clipperElement);
  });
} // Gets the maximum area that the element is visible in due to any number of
// clipping parents
1232
1233
function getClippingRect(element, boundary, rootBoundary) {
  var mainClippingParents = boundary === 'clippingParents' ? getClippingParents(element) : [].concat(boundary);
  var clippingParents = [].concat(mainClippingParents, [rootBoundary]);
  var firstClippingParent = clippingParents[0];
  var clippingRect = clippingParents.reduce(function (accRect, clippingParent) {
    var rect = getClientRectFromMixedType(element, clippingParent);
    var decorations = getDecorations(isHTMLElement(clippingParent) ? clippingParent : getDocumentElement(element));
    accRect.top = Math.max(rect.top + decorations.top, accRect.top);
    accRect.right = Math.min(rect.right - decorations.right, accRect.right);
    accRect.bottom = Math.min(rect.bottom - decorations.bottom, accRect.bottom);
    accRect.left = Math.max(rect.left + decorations.left, accRect.left);
    return accRect;
  }, getClientRectFromMixedType(element, firstClippingParent));
  clippingRect.width = clippingRect.right - clippingRect.left;
  clippingRect.height = clippingRect.bottom - clippingRect.top;
  clippingRect.x = clippingRect.left;
  clippingRect.y = clippingRect.top;
  return clippingRect;
}
1253
function getFreshSideObject() {
  return {
    top: 0,
    right: 0,
    bottom: 0,
    left: 0
  };
}
1262
function mergePaddingObject(paddingObject) {
  return Object.assign({}, getFreshSideObject(), {}, paddingObject);
}
1266
function expandToHashMap(value, keys) {
  return keys.reduce(function (hashMap, key) {
    hashMap[key] = value;
    return hashMap;
  }, {});
}
1273
function detectOverflow(state, options) {
  if (options === void 0) {
    options = {};
  }
1278
  var _options = options,
      _options$placement = _options.placement,
      placement = _options$placement === void 0 ? state.placement : _options$placement,
      _options$boundary = _options.boundary,
      boundary = _options$boundary === void 0 ? clippingParents : _options$boundary,
      _options$rootBoundary = _options.rootBoundary,
      rootBoundary = _options$rootBoundary === void 0 ? viewport : _options$rootBoundary,
      _options$elementConte = _options.elementContext,
      elementContext = _options$elementConte === void 0 ? popper : _options$elementConte,
      _options$altBoundary = _options.altBoundary,
      altBoundary = _options$altBoundary === void 0 ? false : _options$altBoundary,
      _options$padding = _options.padding,
      padding = _options$padding === void 0 ? 0 : _options$padding;
  var paddingObject = mergePaddingObject(typeof padding !== 'number' ? padding : expandToHashMap(padding, basePlacements));
  var altContext = elementContext === popper ? reference : popper;
  var referenceElement = state.elements.reference;
  var popperRect = state.rects.popper;
  var element = state.elements[altBoundary ? altContext : elementContext];
  var clippingClientRect = getClippingRect(isElement(element) ? element : getDocumentElement(state.elements.popper), boundary, rootBoundary);
  var referenceClientRect = getBoundingClientRect(referenceElement);
  var popperOffsets = computeOffsets({
    reference: referenceClientRect,
    element: popperRect,
    strategy: 'absolute',
    placement: placement
  });
  var popperClientRect = rectToClientRect(Object.assign({}, popperRect, {}, popperOffsets));
  var elementClientRect = elementContext === popper ? popperClientRect : referenceClientRect; // positive = overflowing the clipping rect
  // 0 or negative = within the clipping rect
1308
  var overflowOffsets = {
    top: clippingClientRect.top - elementClientRect.top + paddingObject.top,
    bottom: elementClientRect.bottom - clippingClientRect.bottom + paddingObject.bottom,
    left: clippingClientRect.left - elementClientRect.left + paddingObject.left,
    right: elementClientRect.right - clippingClientRect.right + paddingObject.right
  };
  var offsetData = state.modifiersData.offset; // Offsets can be applied only to the popper element
1316
  if (elementContext === popper && offsetData) {
    var offset = offsetData[placement];
    Object.keys(overflowOffsets).forEach(function (key) {
      var multiply = [right, bottom].indexOf(key) >= 0 ? 1 : -1;
      var axis = [top, bottom].indexOf(key) >= 0 ? 'y' : 'x';
      overflowOffsets[key] += offset[axis] * multiply;
    });
  }
1325
  return overflowOffsets;
}
1328
function computeAutoPlacement(state, options) {
  if (options === void 0) {
    options = {};
  }
1333
  var _options = options,
      placement = _options.placement,
      boundary = _options.boundary,
      rootBoundary = _options.rootBoundary,
      padding = _options.padding,
      flipVariations = _options.flipVariations;
  var variation = getVariation(placement);
  var placements = variation ? flipVariations ? variationPlacements : variationPlacements.filter(function (placement) {
    return getVariation(placement) === variation;
  }) : basePlacements; // $FlowFixMe: Flow seems to have problems with two array unions...
1344
  var overflows = placements.reduce(function (acc, placement) {
    acc[placement] = detectOverflow(state, {
      placement: placement,
      boundary: boundary,
      rootBoundary: rootBoundary,
      padding: padding
    })[getBasePlacement(placement)];
    return acc;
  }, {});
  return Object.keys(overflows).sort(function (a, b) {
    return overflows[a] - overflows[b];
  });
}
1358
function getExpandedFallbackPlacements(placement) {
  if (getBasePlacement(placement) === auto) {
    return [];
  }
1363
  var oppositePlacement = getOppositePlacement(placement);
  return [getOppositeVariationPlacement(placement), oppositePlacement, getOppositeVariationPlacement(oppositePlacement)];
}
1367
function flip(_ref) {
  var state = _ref.state,
      options = _ref.options,
      name = _ref.name;
1372
  if (state.modifiersData[name]._skip) {
    return;
  }
1376
  var specifiedFallbackPlacements = options.fallbackPlacements,
      padding = options.padding,
      boundary = options.boundary,
      rootBoundary = options.rootBoundary,
      _options$flipVariatio = options.flipVariations,
      flipVariations = _options$flipVariatio === void 0 ? true : _options$flipVariatio;
  var preferredPlacement = state.options.placement;
  var basePlacement = getBasePlacement(preferredPlacement);
  var isBasePlacement = basePlacement === preferredPlacement;
  var fallbackPlacements = specifiedFallbackPlacements || (isBasePlacement || !flipVariations ? [getOppositePlacement(preferredPlacement)] : getExpandedFallbackPlacements(preferredPlacement));
  var placements = [preferredPlacement].concat(fallbackPlacements).reduce(function (acc, placement) {
    return acc.concat(getBasePlacement(placement) === auto ? computeAutoPlacement(state, {
      placement: placement,
      boundary: boundary,
      rootBoundary: rootBoundary,
      padding: padding,
      flipVariations: flipVariations
    }) : placement);
  }, []);
  var referenceRect = state.rects.reference;
  var popperRect = state.rects.popper;
  var checksMap = new Map();
  var makeFallbackChecks = true;
  var firstFittingPlacement = placements[0];
1401
  for (var i = 0; i < placements.length; i++) {
    var placement = placements[i];
1404
    var _basePlacement = getBasePlacement(placement);
1406
    var isStartVariation = getVariation(placement) === start;
    var isVertical = [top, bottom].indexOf(_basePlacement) >= 0;
    var len = isVertical ? 'width' : 'height';
    var overflow = detectOverflow(state, {
      placement: placement,
      boundary: boundary,
      rootBoundary: rootBoundary,
      padding: padding
    });
    var mainVariationSide = isVertical ? isStartVariation ? right : left : isStartVariation ? bottom : top;
1417
    if (referenceRect[len] > popperRect[len]) {
      mainVariationSide = getOppositePlacement(mainVariationSide);
    }
1421
    var altVariationSide = getOppositePlacement(mainVariationSide);
    var checks = [overflow[_basePlacement] <= 0, overflow[mainVariationSide] <= 0, overflow[altVariationSide] <= 0];
1424
    if (checks.every(function (check) {
      return check;
    })) {
      firstFittingPlacement = placement;
      makeFallbackChecks = false;
      break;
    }
1432
    checksMap.set(placement, checks);
  }
1435
  if (makeFallbackChecks) {
    // `2` may be desired in some cases – research later
    var numberOfChecks = flipVariations ? 3 : 1;
1439
    var _loop = function _loop(_i) {
      var fittingPlacement = placements.find(function (placement) {
        var checks = checksMap.get(placement);
1443
        if (checks) {
          return checks.slice(0, _i).every(function (check) {
            return check;
          });
        }
      });
1450
      if (fittingPlacement) {
        firstFittingPlacement = fittingPlacement;
        return "break";
      }
    };
1456
    for (var _i = numberOfChecks; _i > 0; _i--) {
      var _ret = _loop(_i);
1459
      if (_ret === "break") break;
    }
  }
1463
  if (state.placement !== firstFittingPlacement) {
    state.modifiersData[name]._skip = true;
    state.placement = firstFittingPlacement;
    state.reset = true;
  }
}
1470
var flip$1 = {
  name: 'flip',
  enabled: true,
  phase: 'main',
  fn: flip,
  requiresIfExists: ['offset'],
  data: {
    _skip: false
  }
};
1481
function getAltAxis(axis) {
  return axis === 'x' ? 'y' : 'x';
}
1485
function within(min, value, max) {
  return Math.max(min, Math.min(value, max));
}
1489
function preventOverflow(_ref) {
  var state = _ref.state,
      options = _ref.options,
      name = _ref.name;
  var _options$mainAxis = options.mainAxis,
      checkMainAxis = _options$mainAxis === void 0 ? true : _options$mainAxis,
      _options$altAxis = options.altAxis,
      checkAltAxis = _options$altAxis === void 0 ? false : _options$altAxis,
      boundary = options.boundary,
      rootBoundary = options.rootBoundary,
      padding = options.padding,
      _options$tether = options.tether,
      tether = _options$tether === void 0 ? true : _options$tether,
      _options$tetherOffset = options.tetherOffset,
      tetherOffset = _options$tetherOffset === void 0 ? 0 : _options$tetherOffset;
  var overflow = detectOverflow(state, {
    boundary: boundary,
    rootBoundary: rootBoundary,
    padding: padding
  });
  var basePlacement = getBasePlacement(state.placement);
  var variation = getVariation(state.placement);
  var isBasePlacement = !variation;
  var mainAxis = getMainAxisFromPlacement(basePlacement);
  var altAxis = getAltAxis(mainAxis);
  var popperOffsets = state.modifiersData.popperOffsets;
  var referenceRect = state.rects.reference;
  var popperRect = state.rects.popper;
  var tetherOffsetValue = typeof tetherOffset === 'function' ? tetherOffset(Object.assign({}, state.rects, {
    placement: state.placement
  })) : tetherOffset;
  var data = {
    x: 0,
    y: 0
  };
1525
  if (checkMainAxis) {
    var mainSide = mainAxis === 'y' ? top : left;
    var altSide = mainAxis === 'y' ? bottom : right;
    var len = mainAxis === 'y' ? 'height' : 'width';
    var offset = popperOffsets[mainAxis];
    var min = popperOffsets[mainAxis] + overflow[mainSide];
    var max = popperOffsets[mainAxis] - overflow[altSide];
    var additive = tether ? -popperRect[len] / 2 : 0;
    var minLen = variation === start ? referenceRect[len] : popperRect[len];
    var maxLen = variation === start ? -popperRect[len] : -referenceRect[len]; // We need to include the arrow in the calculation so the arrow doesn't go
    // outside the reference bounds
1537
    var arrowElement = state.elements.arrow;
    var arrowRect = tether && arrowElement ? getLayoutRect(arrowElement) : {
      width: 0,
      height: 0
    };
    var arrowPaddingObject = state.modifiersData['arrow#persistent'] ? state.modifiersData['arrow#persistent'].padding : getFreshSideObject();
    var arrowPaddingMin = arrowPaddingObject[mainSide];
    var arrowPaddingMax = arrowPaddingObject[altSide]; // If the reference length is smaller than the arrow length, we don't want
    // to include its full size in the calculation. If the reference is small
    // and near the edge of a boundary, the popper can overflow even if the
    // reference is not overflowing as well (e.g. virtual elements with no
    // width or height)
1550
    var arrowLen = within(0, referenceRect[len], arrowRect[len]);
    var minOffset = isBasePlacement ? referenceRect[len] / 2 - additive - arrowLen - arrowPaddingMin - tetherOffsetValue : minLen - arrowLen - arrowPaddingMin - tetherOffsetValue;
    var maxOffset = isBasePlacement ? -referenceRect[len] / 2 + additive + arrowLen + arrowPaddingMax + tetherOffsetValue : maxLen + arrowLen + arrowPaddingMax + tetherOffsetValue;
    var offsetModifierValue = state.modifiersData.offset ? state.modifiersData.offset[state.placement][mainAxis] : 0;
    var tetherMin = popperOffsets[mainAxis] + minOffset - offsetModifierValue;
    var tetherMax = popperOffsets[mainAxis] + maxOffset - offsetModifierValue;
    var preventedOffset = within(tether ? Math.min(min, tetherMin) : min, offset, tether ? Math.max(max, tetherMax) : max);
    popperOffsets[mainAxis] = preventedOffset;
    data[mainAxis] = preventedOffset - offset;
  }
1561
  if (checkAltAxis) {
    var _mainSide = mainAxis === 'x' ? top : left;
1564
    var _altSide = mainAxis === 'x' ? bottom : right;
1566
    var _offset = popperOffsets[altAxis];
1568
    var _min = _offset + overflow[_mainSide];
1570
    var _max = _offset - overflow[_altSide];
1572
    var _preventedOffset = within(_min, _offset, _max);
1574
    state.modifiersData.popperOffsets[altAxis] = _preventedOffset;
    data[altAxis] = _preventedOffset - _offset;
  }
1578
  state.modifiersData[name] = data;
}
1581
var preventOverflow$1 = {
  name: 'preventOverflow',
  enabled: true,
  phase: 'main',
  fn: preventOverflow,
  requiresIfExists: ['offset']
};
1589
function arrow(_ref) {
  var _state$modifiersData$;
1592
  var state = _ref.state,
      name = _ref.name;
  var arrowElement = state.elements.arrow;
  var popperOffsets = state.modifiersData.popperOffsets;
  var basePlacement = getBasePlacement(state.placement);
  var axis = getMainAxisFromPlacement(basePlacement);
  var isVertical = [left, right].indexOf(basePlacement) >= 0;
  var len = isVertical ? 'height' : 'width';
1601
  if (!arrowElement) {
    return;
  }
1605
  var paddingObject = state.modifiersData[name + "#persistent"].padding;
  var arrowRect = getLayoutRect(arrowElement);
  var minProp = axis === 'y' ? top : left;
  var maxProp = axis === 'y' ? bottom : right;
  var endDiff = state.rects.reference[len] + state.rects.reference[axis] - popperOffsets[axis] - state.rects.popper[len];
  var startDiff = popperOffsets[axis] - state.rects.reference[axis];
  var centerToReference = endDiff / 2 - startDiff / 2; // Make sure the arrow doesn't overflow the popper if the center point is
  // outside of the popper bounds
1614
  var center = within(paddingObject[minProp], state.rects.popper[len] / 2 - arrowRect[len] / 2 + centerToReference, state.rects.popper[len] - arrowRect[len] - paddingObject[maxProp]); // Prevents breaking syntax highlighting...
1616
  var axisProp = axis;
  state.modifiersData[name] = (_state$modifiersData$ = {}, _state$modifiersData$[axisProp] = center, _state$modifiersData$);
}
1620
function effect$2(_ref2) {
  var state = _ref2.state,
      options = _ref2.options,
      name = _ref2.name;
  var _options$element = options.element,
      arrowElement = _options$element === void 0 ? '[data-popper-arrow]' : _options$element,
      _options$padding = options.padding,
      padding = _options$padding === void 0 ? 0 : _options$padding; // CSS selector
1629
  if (typeof arrowElement === 'string') {
    arrowElement = state.elements.popper.querySelector(arrowElement);
1632
    if (!arrowElement) {
      return;
    }
  }
1637
  if (!contains(state.elements.popper, arrowElement)) {
    {
      console.error(['Popper: "arrow" modifier\'s `element` must be a child of the popper', 'element.'].join(' '));
    }
1642
    return;
  }
1645
  state.elements.arrow = arrowElement;
  state.modifiersData[name + "#persistent"] = {
    padding: mergePaddingObject(typeof padding !== 'number' ? padding : expandToHashMap(padding, basePlacements))
  };
}
1651
var arrow$1 = {
  name: 'arrow',
  enabled: true,
  phase: 'main',
  fn: arrow,
  effect: effect$2,
  requires: ['popperOffsets'],
  requiresIfExists: ['preventOverflow']
};
1661
function getSideOffsets(overflow, rect, preventedOffsets) {
  if (preventedOffsets === void 0) {
    preventedOffsets = {
      x: 0,
      y: 0
    };
  }
1669
  return {
    top: overflow.top - rect.height - preventedOffsets.y,
    right: overflow.right - rect.width + preventedOffsets.x,
    bottom: overflow.bottom - rect.height + preventedOffsets.y,
    left: overflow.left - rect.width - preventedOffsets.x
  };
}
1677
function isAnySideFullyClipped(overflow) {
  return [top, right, bottom, left].some(function (side) {
    return overflow[side] >= 0;
  });
}
1683
function hide(_ref) {
  var state = _ref.state,
      name = _ref.name;
  var referenceRect = state.rects.reference;
  var popperRect = state.rects.popper;
  var preventedOffsets = state.modifiersData.preventOverflow;
  var referenceOverflow = detectOverflow(state, {
    elementContext: 'reference'
  });
  var popperAltOverflow = detectOverflow(state, {
    altBoundary: true
  });
  var referenceClippingOffsets = getSideOffsets(referenceOverflow, referenceRect);
  var popperEscapeOffsets = getSideOffsets(popperAltOverflow, popperRect, preventedOffsets);
  var isReferenceHidden = isAnySideFullyClipped(referenceClippingOffsets);
  var hasPopperEscaped = isAnySideFullyClipped(popperEscapeOffsets);
  state.modifiersData[name] = {
    referenceClippingOffsets: referenceClippingOffsets,
    popperEscapeOffsets: popperEscapeOffsets,
    isReferenceHidden: isReferenceHidden,
    hasPopperEscaped: hasPopperEscaped
  };
  state.attributes.popper = Object.assign({}, state.attributes.popper, {
    'data-popper-reference-hidden': isReferenceHidden,
    'data-popper-escaped': hasPopperEscaped
  });
}
1711
var hide$1 = {
  name: 'hide',
  enabled: true,
  phase: 'main',
  requiresIfExists: ['preventOverflow'],
  fn: hide
};
1719
var defaultModifiers = [eventListeners, popperOffsets$1, computeStyles$1, applyStyles$1, offset$1, flip$1, preventOverflow$1, arrow$1, hide$1];
var createPopper =
/*#__PURE__*/
popperGenerator({
  defaultModifiers: defaultModifiers
}); // eslint-disable-next-line import/no-unused-modules
1726
exports.createPopper = createPopper;
exports.defaultModifiers = defaultModifiers;
exports.popperGenerator = popperGenerator;
1730
Object.defineProperty(exports, '__esModule', { value: true });
1732
1733})));
1734//# sourceMappingURL=popper.js.map
1	`/**`
2	`* @popperjs/core v2.0.6 - MIT License`
3	`*/`
4
5	`(function (global, factory) {`
6	`typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :`
7	`typeof define === 'function' && define.amd ? define(['exports'], factory) :`
8	`(global = global \|\| self, factory(global.Popper = {}));`
9	`}(this, (function (exports) { 'use strict';`
10
11	`function getBoundingClientRect(element) {`
12	`var rect = element.getBoundingClientRect();`
13	`return {`
14	`width: rect.width,`
15	`height: rect.height,`
16	`top: rect.top,`
17	`right: rect.right,`
18	`bottom: rect.bottom,`
19	`left: rect.left,`
20	`x: rect.left,`
21	`y: rect.top`
22	`};`
23	`}`
24
25	`/:: import type { Window } from '../types'; /`
26
27	`/:: declare function getWindow(node: Node \| Window): Window; /`
28	`function getWindow(node) {`
29	`if (node.toString() !== '[object Window]') {`
30	`var ownerDocument = node.ownerDocument;`
31	`return ownerDocument ? ownerDocument.defaultView : window;`
32	`}`
33
34	`return node;`
35	`}`
36
37	`function getWindowScroll(node) {`
38	`var win = getWindow(node);`
39	`var scrollLeft = win.pageXOffset;`
40	`var scrollTop = win.pageYOffset;`