popper-base.js 31.6 KB
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/**
 * @popperjs/core v2.11.8 - MIT License
 */

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
  typeof define === 'function' && define.amd ? define(['exports'], factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.Popper = {}));
}(this, (function (exports) { 'use strict';

  function getWindow(node) {
    if (node == null) {
      return window;
    }

    if (node.toString() !== '[object Window]') {
      var ownerDocument = node.ownerDocument;
      return ownerDocument ? ownerDocument.defaultView || window : window;
    }

    return node;
  }

  function isElement(node) {
    var OwnElement = getWindow(node).Element;
    return node instanceof OwnElement || node instanceof Element;
  }

  function isHTMLElement(node) {
    var OwnElement = getWindow(node).HTMLElement;
    return node instanceof OwnElement || node instanceof HTMLElement;
  }

  function isShadowRoot(node) {
    // IE 11 has no ShadowRoot
    if (typeof ShadowRoot === 'undefined') {
      return false;
    }

    var OwnElement = getWindow(node).ShadowRoot;
    return node instanceof OwnElement || node instanceof ShadowRoot;
  }

  var max = Math.max;
  var min = Math.min;
  var round = Math.round;

  function getUAString() {
    var uaData = navigator.userAgentData;

    if (uaData != null && uaData.brands && Array.isArray(uaData.brands)) {
      return uaData.brands.map(function (item) {
        return item.brand + "/" + item.version;
      }).join(' ');
    }

    return navigator.userAgent;
  }

  function isLayoutViewport() {
    return !/^((?!chrome|android).)*safari/i.test(getUAString());
  }

  function getBoundingClientRect(element, includeScale, isFixedStrategy) {
    if (includeScale === void 0) {
      includeScale = false;
    }

    if (isFixedStrategy === void 0) {
      isFixedStrategy = false;
    }

    var clientRect = element.getBoundingClientRect();
    var scaleX = 1;
    var scaleY = 1;

    if (includeScale && isHTMLElement(element)) {
      scaleX = element.offsetWidth > 0 ? round(clientRect.width) / element.offsetWidth || 1 : 1;
      scaleY = element.offsetHeight > 0 ? round(clientRect.height) / element.offsetHeight || 1 : 1;
    }

    var _ref = isElement(element) ? getWindow(element) : window,
        visualViewport = _ref.visualViewport;

    var addVisualOffsets = !isLayoutViewport() && isFixedStrategy;
    var x = (clientRect.left + (addVisualOffsets && visualViewport ? visualViewport.offsetLeft : 0)) / scaleX;
    var y = (clientRect.top + (addVisualOffsets && visualViewport ? visualViewport.offsetTop : 0)) / scaleY;
    var width = clientRect.width / scaleX;
    var height = clientRect.height / scaleY;
    return {
      width: width,
      height: height,
      top: y,
      right: x + width,
      bottom: y + height,
      left: x,
      x: x,
      y: y
    };
  }

  function getWindowScroll(node) {
    var win = getWindow(node);
    var scrollLeft = win.pageXOffset;
    var scrollTop = win.pageYOffset;
    return {
      scrollLeft: scrollLeft,
      scrollTop: scrollTop
    };
  }

  function getHTMLElementScroll(element) {
    return {
      scrollLeft: element.scrollLeft,
      scrollTop: element.scrollTop
    };
  }

  function getNodeScroll(node) {
    if (node === getWindow(node) || !isHTMLElement(node)) {
      return getWindowScroll(node);
    } else {
      return getHTMLElementScroll(node);
    }
  }

  function getNodeName(element) {
    return element ? (element.nodeName || '').toLowerCase() : null;
  }

  function getDocumentElement(element) {
    // $FlowFixMe[incompatible-return]: assume body is always available
    return ((isElement(element) ? element.ownerDocument : // $FlowFixMe[prop-missing]
    element.document) || window.document).documentElement;
  }

  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;
  }

  function getComputedStyle(element) {
    return getWindow(element).getComputedStyle(element);
  }

  function isScrollParent(element) {
    // Firefox wants us to check `-x` and `-y` variations as well
    var _getComputedStyle = getComputedStyle(element),
        overflow = _getComputedStyle.overflow,
        overflowX = _getComputedStyle.overflowX,
        overflowY = _getComputedStyle.overflowY;

    return /auto|scroll|overlay|hidden/.test(overflow + overflowY + overflowX);
  }

  function isElementScaled(element) {
    var rect = element.getBoundingClientRect();
    var scaleX = round(rect.width) / element.offsetWidth || 1;
    var scaleY = round(rect.height) / element.offsetHeight || 1;
    return scaleX !== 1 || scaleY !== 1;
  } // Returns the composite rect of an element relative to its offsetParent.
  // Composite means it takes into account transforms as well as layout.


  function getCompositeRect(elementOrVirtualElement, offsetParent, isFixed) {
    if (isFixed === void 0) {
      isFixed = false;
    }

    var isOffsetParentAnElement = isHTMLElement(offsetParent);
    var offsetParentIsScaled = isHTMLElement(offsetParent) && isElementScaled(offsetParent);
    var documentElement = getDocumentElement(offsetParent);
    var rect = getBoundingClientRect(elementOrVirtualElement, offsetParentIsScaled, isFixed);
    var scroll = {
      scrollLeft: 0,
      scrollTop: 0
    };
    var offsets = {
      x: 0,
      y: 0
    };

    if (isOffsetParentAnElement || !isOffsetParentAnElement && !isFixed) {
      if (getNodeName(offsetParent) !== 'body' || // https://github.com/popperjs/popper-core/issues/1078
      isScrollParent(documentElement)) {
        scroll = getNodeScroll(offsetParent);
      }

      if (isHTMLElement(offsetParent)) {
        offsets = getBoundingClientRect(offsetParent, true);
        offsets.x += offsetParent.clientLeft;
        offsets.y += offsetParent.clientTop;
      } else if (documentElement) {
        offsets.x = getWindowScrollBarX(documentElement);
      }
    }

    return {
      x: rect.left + scroll.scrollLeft - offsets.x,
      y: rect.top + scroll.scrollTop - offsets.y,
      width: rect.width,
      height: rect.height
    };
  }

  // means it doesn't take into account transforms.

  function getLayoutRect(element) {
    var clientRect = getBoundingClientRect(element); // Use the clientRect sizes if it's not been transformed.
    // Fixes https://github.com/popperjs/popper-core/issues/1223

    var width = element.offsetWidth;
    var height = element.offsetHeight;

    if (Math.abs(clientRect.width - width) <= 1) {
      width = clientRect.width;
    }

    if (Math.abs(clientRect.height - height) <= 1) {
      height = clientRect.height;
    }

    return {
      x: element.offsetLeft,
      y: element.offsetTop,
      width: width,
      height: height
    };
  }

  function getParentNode(element) {
    if (getNodeName(element) === 'html') {
      return element;
    }

    return (// this is a quicker (but less type safe) way to save quite some bytes from the bundle
      // $FlowFixMe[incompatible-return]
      // $FlowFixMe[prop-missing]
      element.assignedSlot || // step into the shadow DOM of the parent of a slotted node
      element.parentNode || ( // DOM Element detected
      isShadowRoot(element) ? element.host : null) || // ShadowRoot detected
      // $FlowFixMe[incompatible-call]: HTMLElement is a Node
      getDocumentElement(element) // fallback

    );
  }

  function getScrollParent(node) {
    if (['html', 'body', '#document'].indexOf(getNodeName(node)) >= 0) {
      // $FlowFixMe[incompatible-return]: assume body is always available
      return node.ownerDocument.body;
    }

    if (isHTMLElement(node) && isScrollParent(node)) {
      return node;
    }

    return getScrollParent(getParentNode(node));
  }

  /*
  given a DOM element, return the list of all scroll parents, up the list of ancesors
  until we get to the top window object. This list is what we attach scroll listeners
  to, because if any of these parent elements scroll, we'll need to re-calculate the
  reference element's position.
  */

  function listScrollParents(element, list) {
    var _element$ownerDocumen;

    if (list === void 0) {
      list = [];
    }

    var scrollParent = getScrollParent(element);
    var isBody = scrollParent === ((_element$ownerDocumen = element.ownerDocument) == null ? void 0 : _element$ownerDocumen.body);
    var win = getWindow(scrollParent);
    var target = isBody ? [win].concat(win.visualViewport || [], isScrollParent(scrollParent) ? scrollParent : []) : scrollParent;
    var updatedList = list.concat(target);
    return isBody ? updatedList : // $FlowFixMe[incompatible-call]: isBody tells us target will be an HTMLElement here
    updatedList.concat(listScrollParents(getParentNode(target)));
  }

  function isTableElement(element) {
    return ['table', 'td', 'th'].indexOf(getNodeName(element)) >= 0;
  }

  function getTrueOffsetParent(element) {
    if (!isHTMLElement(element) || // https://github.com/popperjs/popper-core/issues/837
    getComputedStyle(element).position === 'fixed') {
      return null;
    }

    return element.offsetParent;
  } // `.offsetParent` reports `null` for fixed elements, while absolute elements
  // return the containing block


  function getContainingBlock(element) {
    var isFirefox = /firefox/i.test(getUAString());
    var isIE = /Trident/i.test(getUAString());

    if (isIE && isHTMLElement(element)) {
      // In IE 9, 10 and 11 fixed elements containing block is always established by the viewport
      var elementCss = getComputedStyle(element);

      if (elementCss.position === 'fixed') {
        return null;
      }
    }

    var currentNode = getParentNode(element);

    if (isShadowRoot(currentNode)) {
      currentNode = currentNode.host;
    }

    while (isHTMLElement(currentNode) && ['html', 'body'].indexOf(getNodeName(currentNode)) < 0) {
      var css = getComputedStyle(currentNode); // This is non-exhaustive but covers the most common CSS properties that
      // create a containing block.
      // https://developer.mozilla.org/en-US/docs/Web/CSS/Containing_block#identifying_the_containing_block

      if (css.transform !== 'none' || css.perspective !== 'none' || css.contain === 'paint' || ['transform', 'perspective'].indexOf(css.willChange) !== -1 || isFirefox && css.willChange === 'filter' || isFirefox && css.filter && css.filter !== 'none') {
        return currentNode;
      } else {
        currentNode = currentNode.parentNode;
      }
    }

    return null;
  } // Gets the closest ancestor positioned element. Handles some edge cases,
  // such as table ancestors and cross browser bugs.


  function getOffsetParent(element) {
    var window = getWindow(element);
    var offsetParent = getTrueOffsetParent(element);

    while (offsetParent && isTableElement(offsetParent) && getComputedStyle(offsetParent).position === 'static') {
      offsetParent = getTrueOffsetParent(offsetParent);
    }

    if (offsetParent && (getNodeName(offsetParent) === 'html' || getNodeName(offsetParent) === 'body' && getComputedStyle(offsetParent).position === 'static')) {
      return window;
    }

    return offsetParent || getContainingBlock(element) || window;
  }

  var top = 'top';
  var bottom = 'bottom';
  var right = 'right';
  var left = 'left';
  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 beforeRead = 'beforeRead';
  var read = 'read';
  var afterRead = 'afterRead'; // pure-logic modifiers

  var beforeMain = 'beforeMain';
  var main = 'main';
  var afterMain = 'afterMain'; // modifier with the purpose to write to the DOM (or write into a framework state)

  var beforeWrite = 'beforeWrite';
  var write = 'write';
  var afterWrite = 'afterWrite';
  var modifierPhases = [beforeRead, read, afterRead, beforeMain, main, afterMain, beforeWrite, write, afterWrite];

  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

    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);

          if (depModifier) {
            sort(depModifier);
          }
        }
      });
      result.push(modifier);
    }

    modifiers.forEach(function (modifier) {
      if (!visited.has(modifier.name)) {
        // check for visited object
        sort(modifier);
      }
    });
    return result;
  }

  function orderModifiers(modifiers) {
    // order based on dependencies
    var orderedModifiers = order(modifiers); // order based on phase

    return modifierPhases.reduce(function (acc, phase) {
      return acc.concat(orderedModifiers.filter(function (modifier) {
        return modifier.phase === phase;
      }));
    }, []);
  }

  function debounce(fn) {
    var pending;
    return function () {
      if (!pending) {
        pending = new Promise(function (resolve) {
          Promise.resolve().then(function () {
            pending = undefined;
            resolve(fn());
          });
        });
      }

      return pending;
    };
  }

  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

    return Object.keys(merged).map(function (key) {
      return merged[key];
    });
  }

  function getViewportRect(element, strategy) {
    var win = getWindow(element);
    var html = getDocumentElement(element);
    var visualViewport = win.visualViewport;
    var width = html.clientWidth;
    var height = html.clientHeight;
    var x = 0;
    var y = 0;

    if (visualViewport) {
      width = visualViewport.width;
      height = visualViewport.height;
      var layoutViewport = isLayoutViewport();

      if (layoutViewport || !layoutViewport && strategy === 'fixed') {
        x = visualViewport.offsetLeft;
        y = visualViewport.offsetTop;
      }
    }

    return {
      width: width,
      height: height,
      x: x + getWindowScrollBarX(element),
      y: y
    };
  }

  // of the `<html>` and `<body>` rect bounds if horizontally scrollable

  function getDocumentRect(element) {
    var _element$ownerDocumen;

    var html = getDocumentElement(element);
    var winScroll = getWindowScroll(element);
    var body = (_element$ownerDocumen = element.ownerDocument) == null ? void 0 : _element$ownerDocumen.body;
    var width = max(html.scrollWidth, html.clientWidth, body ? body.scrollWidth : 0, body ? body.clientWidth : 0);
    var height = max(html.scrollHeight, html.clientHeight, body ? body.scrollHeight : 0, body ? body.clientHeight : 0);
    var x = -winScroll.scrollLeft + getWindowScrollBarX(element);
    var y = -winScroll.scrollTop;

    if (getComputedStyle(body || html).direction === 'rtl') {
      x += max(html.clientWidth, body ? body.clientWidth : 0) - width;
    }

    return {
      width: width,
      height: height,
      x: x,
      y: y
    };
  }

  function contains(parent, child) {
    var rootNode = child.getRootNode && child.getRootNode(); // First, attempt with faster native method

    if (parent.contains(child)) {
      return true;
    } // then fallback to custom implementation with Shadow DOM support
    else if (rootNode && isShadowRoot(rootNode)) {
        var next = child;

        do {
          if (next && parent.isSameNode(next)) {
            return true;
          } // $FlowFixMe[prop-missing]: need a better way to handle this...


          next = next.parentNode || next.host;
        } while (next);
      } // Give up, the result is false


    return false;
  }

  function rectToClientRect(rect) {
    return Object.assign({}, rect, {
      left: rect.x,
      top: rect.y,
      right: rect.x + rect.width,
      bottom: rect.y + rect.height
    });
  }

  function getInnerBoundingClientRect(element, strategy) {
    var rect = getBoundingClientRect(element, false, strategy === 'fixed');
    rect.top = rect.top + element.clientTop;
    rect.left = rect.left + element.clientLeft;
    rect.bottom = rect.top + element.clientHeight;
    rect.right = rect.left + element.clientWidth;
    rect.width = element.clientWidth;
    rect.height = element.clientHeight;
    rect.x = rect.left;
    rect.y = rect.top;
    return rect;
  }

  function getClientRectFromMixedType(element, clippingParent, strategy) {
    return clippingParent === viewport ? rectToClientRect(getViewportRect(element, strategy)) : isElement(clippingParent) ? getInnerBoundingClientRect(clippingParent, strategy) : 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`


  function getClippingParents(element) {
    var clippingParents = listScrollParents(getParentNode(element));
    var canEscapeClipping = ['absolute', 'fixed'].indexOf(getComputedStyle(element).position) >= 0;
    var clipperElement = canEscapeClipping && isHTMLElement(element) ? getOffsetParent(element) : element;

    if (!isElement(clipperElement)) {
      return [];
    } // $FlowFixMe[incompatible-return]: https://github.com/facebook/flow/issues/1414


    return clippingParents.filter(function (clippingParent) {
      return isElement(clippingParent) && contains(clippingParent, clipperElement) && getNodeName(clippingParent) !== 'body';
    });
  } // Gets the maximum area that the element is visible in due to any number of
  // clipping parents


  function getClippingRect(element, boundary, rootBoundary, strategy) {
    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, strategy);
      accRect.top = max(rect.top, accRect.top);
      accRect.right = min(rect.right, accRect.right);
      accRect.bottom = min(rect.bottom, accRect.bottom);
      accRect.left = max(rect.left, accRect.left);
      return accRect;
    }, getClientRectFromMixedType(element, firstClippingParent, strategy));
    clippingRect.width = clippingRect.right - clippingRect.left;
    clippingRect.height = clippingRect.bottom - clippingRect.top;
    clippingRect.x = clippingRect.left;
    clippingRect.y = clippingRect.top;
    return clippingRect;
  }

  function getBasePlacement(placement) {
    return placement.split('-')[0];
  }

  function getVariation(placement) {
    return placement.split('-')[1];
  }

  function getMainAxisFromPlacement(placement) {
    return ['top', 'bottom'].indexOf(placement) >= 0 ? 'x' : 'y';
  }

  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;

    switch (basePlacement) {
      case top:
        offsets = {
          x: commonX,
          y: reference.y - element.height
        };
        break;

      case bottom:
        offsets = {
          x: commonX,
          y: reference.y + reference.height
        };
        break;

      case right:
        offsets = {
          x: reference.x + reference.width,
          y: commonY
        };
        break;

      case left:
        offsets = {
          x: reference.x - element.width,
          y: commonY
        };
        break;

      default:
        offsets = {
          x: reference.x,
          y: reference.y
        };
    }

    var mainAxis = basePlacement ? getMainAxisFromPlacement(basePlacement) : null;

    if (mainAxis != null) {
      var len = mainAxis === 'y' ? 'height' : 'width';

      switch (variation) {
        case start:
          offsets[mainAxis] = offsets[mainAxis] - (reference[len] / 2 - element[len] / 2);
          break;

        case end:
          offsets[mainAxis] = offsets[mainAxis] + (reference[len] / 2 - element[len] / 2);
          break;
      }
    }

    return offsets;
  }

  function getFreshSideObject() {
    return {
      top: 0,
      right: 0,
      bottom: 0,
      left: 0
    };
  }

  function mergePaddingObject(paddingObject) {
    return Object.assign({}, getFreshSideObject(), paddingObject);
  }

  function expandToHashMap(value, keys) {
    return keys.reduce(function (hashMap, key) {
      hashMap[key] = value;
      return hashMap;
    }, {});
  }

  function detectOverflow(state, options) {
    if (options === void 0) {
      options = {};
    }

    var _options = options,
        _options$placement = _options.placement,
        placement = _options$placement === void 0 ? state.placement : _options$placement,
        _options$strategy = _options.strategy,
        strategy = _options$strategy === void 0 ? state.strategy : _options$strategy,
        _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 popperRect = state.rects.popper;
    var element = state.elements[altBoundary ? altContext : elementContext];
    var clippingClientRect = getClippingRect(isElement(element) ? element : element.contextElement || getDocumentElement(state.elements.popper), boundary, rootBoundary, strategy);
    var referenceClientRect = getBoundingClientRect(state.elements.reference);
    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

    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

    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;
      });
    }

    return overflowOffsets;
  }

  var DEFAULT_OPTIONS = {
    placement: 'bottom',
    modifiers: [],
    strategy: 'absolute'
  };

  function areValidElements() {
    for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
      args[_key] = arguments[_key];
    }

    return !args.some(function (element) {
      return !(element && typeof element.getBoundingClientRect === 'function');
    });
  }

  function popperGenerator(generatorOptions) {
    if (generatorOptions === void 0) {
      generatorOptions = {};
    }

    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;
      }

      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(setOptionsAction) {
          var options = typeof setOptionsAction === 'function' ? setOptionsAction(state.options) : setOptionsAction;
          cleanupModifierEffects();
          state.options = Object.assign({}, defaultOptions, state.options, options);
          state.scrollParents = {
            reference: isElement(reference) ? listScrollParents(reference) : reference.contextElement ? listScrollParents(reference.contextElement) : [],
            popper: listScrollParents(popper)
          }; // Orders the modifiers based on their dependencies and `phase`
          // properties

          var orderedModifiers = orderModifiers(mergeByName([].concat(defaultModifiers, state.options.modifiers))); // Strip out disabled modifiers

          state.orderedModifiers = orderedModifiers.filter(function (m) {
            return m.enabled;
          });
          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;
          }

          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

          if (!areValidElements(reference, popper)) {
            return;
          } // Store the reference and popper rects to be read by modifiers


          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

          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`

          state.orderedModifiers.forEach(function (modifier) {
            return state.modifiersData[modifier.name] = Object.assign({}, modifier.data);
          });

          for (var index = 0; index < state.orderedModifiers.length; index++) {
            if (state.reset === true) {
              state.reset = false;
              index = -1;
              continue;
            }

            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;

            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;
        }
      };

      if (!areValidElements(reference, popper)) {
        return instance;
      }

      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.

      function runModifierEffects() {
        state.orderedModifiers.forEach(function (_ref) {
          var name = _ref.name,
              _ref$options = _ref.options,
              options = _ref$options === void 0 ? {} : _ref$options,
              effect = _ref.effect;

          if (typeof effect === 'function') {
            var cleanupFn = effect({
              state: state,
              name: name,
              instance: instance,
              options: options
            });

            var noopFn = function noopFn() {};

            effectCleanupFns.push(cleanupFn || noopFn);
          }
        });
      }

      function cleanupModifierEffects() {
        effectCleanupFns.forEach(function (fn) {
          return fn();
        });
        effectCleanupFns = [];
      }

      return instance;
    };
  }
  var createPopper = /*#__PURE__*/popperGenerator(); // eslint-disable-next-line import/no-unused-modules

  exports.createPopper = createPopper;
  exports.detectOverflow = detectOverflow;
  exports.popperGenerator = popperGenerator;

  Object.defineProperty(exports, '__esModule', { value: true });

})));
//# sourceMappingURL=popper-base.js.map