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	/*!
	* treeDiffer.js
	*
	* Version 1.1.1
	* https://github.com/Tchanders/treeDiffer.js
	*
	* Released under the MIT license
	*/
	( function ( global ) {

	'use strict';

	/*!
	* treeDiffer Namespace for treeDiffer.js
	*
	* Released under the MIT license
	*/

	// eslint-disable-next-line no-redeclare, no-unused-vars
	const treeDiffer = {};

	/*!
	* treeDiffer.TreeNode
	*
	* Released under the MIT license
	*/

	/**
	* TreeNode
	*
	* Abstract TreeNode class for Trees to be diffed. It should be extended,
	* then a Tree should be built by passing the root node and the name of
	* the new class into the Tree constructor.
	*
	* @class
	* @constructor
	* @param {Object} node Object representing a node to be wrapped
	*/
	treeDiffer.TreeNode = function ( node ) {
	/**
	* @property {Object} node Object representing the wrapped node
	*/
	this.node = node;

	/**
	* @property {treeDiffer.TreeNode[]} children Child nodes
	*/
	this.children = [];

	/**
	* @property {number} index Index in node list ordered by deepest-first then document order
	*/
	this.index = null;

	/**
	* @property {number} leftmost Leftmost of this node; see treeDiffer.Tree
	*/
	this.leftmost = null;
	};

	/**
	* Add a node to the list of this node's children
	*
	* @param {treeDiffer.TreeNode} child
	*/
	treeDiffer.TreeNode.prototype.addChild = function ( child ) {
	this.children.push( child );
	child.parent = this;
	};

	/**
	* @method
	* Check if another TreeNode is equal to this node. Conditions for equality
	* will depend on the use case.
	*
	* @param {treeDiffer.TreeNode} other The other TreeNode
	* @return {boolean} True if equal
	*/
	treeDiffer.TreeNode.prototype.isEqual = null;

	/**
	* Get the children of the node that this tree node wraps. How to
	* find and filter children will depend on the use case.
	*
	* @method
	* @return {Object[]} Children of the wrapped node
	*/
	treeDiffer.TreeNode.prototype.getOriginalNodeChildren = null;

	/*!
	* treeDiffer.Tree
	*
	* Released under the MIT license
	*/

	/**
	* Tree
	*
	* A group of TreeNodes connected by parent-child relationships in a tree
	* structure, along with certain properties that define the exact structure of the
	* tree: the node order, the keyroots, and the leftmost node of each node. (Terms
	* defined in: http://epubs.siam.org/doi/abs/10.1137/0218082?journalCode=smjcat)
	*
	* @class
	* @constructor
	*
	* @param {treeDiffer.TreeNode} node Root node of the tree
	* @param {Function} nodeClass Concrete subclass of treeDiffer.TreeNode
	* @param {Object} config Config options for nodeClass
	*/
	treeDiffer.Tree = function ( node, nodeClass, config ) {

	this.root = null;
	this.nodeClass = nodeClass;
	this.orderedNodes = [];
	this.keyRoots = [];

	this.findKeyRootsAndOrderedNodes( node, config );

	};

	/**
	* Find the post-ordering of the tree nodes, the keyroots and the leftmost of each
	* node.
	*
	* @param {Object} node Root node in original tree
	* @param {Object} config Config options for nodeClass
	*/
	treeDiffer.Tree.prototype.findKeyRootsAndOrderedNodes = function ( node, config ) {
	const leftmostsToKeyRoots = {},
	tree = this;

	/**
	* Find the tree nodes in post-order, find the leftmost of each node, and store
	* the order and leftmost as properties of the nodes.
	*
	* @param {treeDiffer.TreeNode} treeNode Node currently being checked
	* @param {Array} orderedNodes Array to be populated with nodes in order
	*/
	function postOrderNodes( treeNode, orderedNodes ) {
	const children = treeNode.getOriginalNodeChildren();

	for ( let i = 0, ilen = children.length; i < ilen; i++ ) {
	// eslint-disable-next-line new-cap
	const childNode = new tree.nodeClass( children[ i ], config );
	treeNode.addChild( childNode );
	postOrderNodes( childNode, orderedNodes );
	}

	// Record node order
	orderedNodes.push( treeNode );
	treeNode.index = orderedNodes.length - 1;

	// Record index of leftmost node
	// If this node is a leaf, it is its own leftmost
	treeNode.leftmost = treeNode.children.length === 0 ? treeNode.index : treeNode.children[ 0 ].leftmost;

	// Update the key root corresponding to this leftmost
	// A keyroot is the higest indexed node with each leftmost
	leftmostsToKeyRoots[ treeNode.leftmost ] = treeNode.index;
	}

	// Store the nodes in order
	// eslint-disable-next-line new-cap
	this.root = new tree.nodeClass( node, config );
	this.orderedNodes = [];
	postOrderNodes( this.root, this.orderedNodes );

	// Store the key roots in order of node index
	for ( const leftmost in leftmostsToKeyRoots ) {
	this.keyRoots.push( leftmostsToKeyRoots[ leftmost ] );
	}
	this.keyRoots.sort( ( a, b ) => a - b );

	};

	/**
	* Get all the descendants of a node
	*
	* @param {treeDiffer.TreeNode} node Node whose descendants to find
	* @return {Array} Descendants of the node
	*/
	treeDiffer.Tree.prototype.getNodeDescendants = function ( node ) {
	const descendants = [];

	function addDescendants( parentNode ) {
	for ( let i = 0, ilen = parentNode.children.length; i < ilen; i++ ) {
	const childNode = parentNode.children[ i ];
	descendants.push( childNode );
	addDescendants( childNode );
	}
	}

	addDescendants( node );

	return descendants;
	};

	/*!
	* treeDiffer.Differ
	*
	* Released under the MIT license
	*/

	/* eslint-disable dot-notation */
	// We use [ 'null' ] as an index, but for consistencty with
	// variable indicies [ i ][ j ] we prefer not to use dot notation

	const fastSliceAndPush = ( arr, item ) => {
	const len = arr.length;
	const result = new Array( len + 1 );
	for ( let i = 0; i < len; i++ ) {
	result[ i ] = arr[ i ];
	}
	result[ len ] = item;
	return result;
	};

	const fastConcat = ( arr1, arr2 ) => {
	const len1 = arr1.length;
	const len2 = arr2.length;
	const result = new Array( len1 + len2 );
	for ( let i = 0; i < len1; i++ ) {
	result[ i ] = arr1[ i ];
	}
	for ( let j = 0; j < len2; j++ ) {
	result[ len1 + j ] = arr2[ j ];
	}
	return result;
	};

	/**
	* Differ
	*
	* Find the minimum transactions to get from the first tree to the second tree. Each
	* transaction is of the form [nodeToRemove, nodeToInsert], where nodeToRemove or
	* nodeToInsert (but not both) can be null. The tree diffing algorithm is presented in:
	* http://epubs.siam.org/doi/abs/10.1137/0218082?journalCode=smjcat
	*
	* @class
	* @constructor
	* @param {treeDiffer.Tree} tree1 First tree
	* @param {treeDiffer.Tree} tree2 Second tree
	* @param {number} [timeout=1000] Timeout after which to stop diffing
	*/
	treeDiffer.Differ = function ( tree1, tree2, timeout ) {

	this.endTime = Date.now() + ( timeout \|\| 1000 );

	this.tree1 = tree1;
	this.tree2 = tree2;

	this.insertCost = 1;
	this.removeCost = 1;
	this.changeCost = 1;

	// Temporary, changing store of transactions
	const transactions = {
	null: {
	null: []
	}
	};

	// Permanent store of transactions such that transactions[x][y] is the minimum
	// transactions to get from the sub-tree rooted at node x (in tree1) to the sub-tree
	// rooted at node y (in tree2).
	this.transactions = {
	null: {}
	};

	// All possible transactions
	this.indexToTransaction = [];
	this.indexToTransaction.push( [ null, null ] );

	let transactionIndex = 0;
	// Indices for each transaction, to avoid high performance cost of creating the
	// transactions multiple times
	this.transactionToIndex = {
	null: {
	null: 0
	}
	};
	transactionIndex += 1;

	// Populate transaction stores
	for ( let i = 0, ilen = this.tree1.orderedNodes.length; i < ilen; i++ ) {

	transactions[ i ] = {
	null: []
	};
	this.transactionToIndex[ i ] = {
	null: transactionIndex
	};
	transactionIndex += 1;
	this.indexToTransaction.push( [ i, null ] );

	for ( let j = 0, jlen = this.tree2.orderedNodes.length; j < jlen; j++ ) {
	transactions[ null ][ j ] = [];
	transactions[ i ][ j ] = [];

	this.transactionToIndex[ null ][ j ] = transactionIndex;
	transactionIndex += 1;
	this.indexToTransaction.push( [ null, j ] );

	this.transactionToIndex[ i ][ j ] = transactionIndex;
	transactionIndex += 1;
	this.indexToTransaction.push( [ i, j ] );
	}

	this.transactions[ i ] = {};

	}

	this.populateTransactions( transactions );
	};

	/**
	* Populate this.transactions with minimum transactions between all possible trees
	*
	* @param {Object} transactions Temporary store of transactions between trees
	*/
	treeDiffer.Differ.prototype.populateTransactions = function ( transactions ) {
	const differ = this;

	function getTransactionFromIndex( index ) {
	return differ.indexToTransaction[ index ];
	}

	for ( let i = 0, ilen = this.tree1.keyRoots.length; i < ilen; i++ ) {

	// Make transactions for tree -> null
	const keyRoot1 = this.tree1.orderedNodes[ this.tree1.keyRoots[ i ] ];
	const iNulls = [];
	for ( let ii = keyRoot1.leftmost; ii < keyRoot1.index + 1; ii++ ) {
	iNulls.push( this.transactionToIndex[ ii ][ null ] );
	transactions[ ii ][ null ] = iNulls.slice();
	}

	for ( let j = 0, jlen = this.tree2.keyRoots.length; j < jlen; j++ ) {

	// Make transactions of null -> tree
	const keyRoot2 = this.tree2.orderedNodes[ this.tree2.keyRoots[ j ] ];
	const jNulls = [];
	for ( let jj = keyRoot2.leftmost; jj < keyRoot2.index + 1; jj++ ) {
	jNulls.push( this.transactionToIndex[ null ][ jj ] );
	transactions[ null ][ jj ] = jNulls.slice();
	}

	// Get the diff
	this.findMinimumTransactions( keyRoot1, keyRoot2, transactions );

	if ( Date.now() > this.endTime ) {
	this.transactions = null;
	return;
	}
	}
	}

	for ( let i = 0, ilen = this.tree1.orderedNodes.length; i < ilen; i++ ) {
	for ( let j = 0, jlen = this.tree2.orderedNodes.length; j < jlen; j++ ) {
	if ( this.transactions[ i ][ j ] && this.transactions[ i ][ j ].length > 0 ) {
	this.transactions[ i ][ j ] = this.transactions[ i ][ j ].map( getTransactionFromIndex );
	}
	}
	}

	};

	/**
	* Get the cost of removing a node from the first tree, inserting a node into the second
	* tree, or relabelling a node from the first tree to a node from the second tree.
	*
	* @param {treeDiffer.TreeNode} node1 Node from the first tree
	* @param {treeDiffer.TreeNode} node2 Node from the second tree]
	* @return {number} Cost of the transaction
	*/
	treeDiffer.Differ.prototype.getNodeDistance = function ( node1, node2 ) {
	if ( node1 === null && node2 === null ) {
	return 0;
	}
	if ( node1 === null ) {
	return this.insertCost;
	}
	if ( node2 === null ) {
	return this.removeCost;
	}
	if ( node1.isEqual( node2 ) ) {
	return 0;
	}
	return this.changeCost;
	};

	const getLowestCost = ( removeCost, insertCost, changeCost ) => {
	// This used to be written as:
	// transaction = costs.indexOf( Math.min.apply( null, costs ) )
	// but expanding into two simple comparisons makes it much faster.
	let minCost = removeCost,
	index = 0;
	if ( insertCost < minCost ) {
	index = 1;
	minCost = insertCost;
	}
	if ( changeCost < minCost ) {
	index = 2;
	}
	return index;
	};

	/**
	* Find the minimum transactions to get from the first tree to the second tree. This
	* method is the heart of the tree differ.
	*
	* @param {treeDiffer.TreeNode} keyRoot1 A keyroot from the first tree
	* @param {treeDiffer.TreeNode} keyRoot2 A keyroot from the second tree
	* @param {Object} transactions Temporary store of transactions between trees
	*/
	treeDiffer.Differ.prototype.findMinimumTransactions = function ( keyRoot1, keyRoot2, transactions ) {

	for ( let i = keyRoot1.leftmost; i < keyRoot1.index + 1; i++ ) {
	const iMinus1 = i === keyRoot1.leftmost ? null : i - 1;
	const orderedNode1 = this.tree1.orderedNodes[ i ];

	for ( let j = keyRoot2.leftmost; j < keyRoot2.index + 1; j++ ) {
	const jMinus1 = j === keyRoot2.leftmost ? null : j - 1;
	const orderedNode2 = this.tree2.orderedNodes[ j ];

	if ( orderedNode1.leftmost === keyRoot1.leftmost && orderedNode2.leftmost === keyRoot2.leftmost ) {

	// Previous transactions, leading up to a remove, insert or change
	const remove = transactions[ iMinus1 ][ j ];
	const insert = transactions[ i ][ jMinus1 ];
	const change = transactions[ iMinus1 ][ jMinus1 ];

	const nodeDistance = this.getNodeDistance( orderedNode1, orderedNode2 );

	// Cost of each transaction
	const transaction = getLowestCost(
	remove.length + this.removeCost,
	insert.length + this.insertCost,
	change.length + nodeDistance
	);

	if ( transaction === 0 ) {
	// Record a remove
	transactions[ i ][ j ] = fastSliceAndPush( remove, this.transactionToIndex[ i ][ null ] );
	} else if ( transaction === 1 ) {
	// Record an insert
	transactions[ i ][ j ] = fastSliceAndPush( insert, this.transactionToIndex[ null ][ j ] );
	} else if ( nodeDistance === 1 ) {
	// If nodes i and j are different, record a change,
	// otherwise there is no transaction
	transactions[ i ][ j ] = fastSliceAndPush( change, this.transactionToIndex[ i ][ j ] );
	} else {
	transactions[ i ][ j ] = change.slice();
	}

	// No need to do a shallow copy here as transactions[ i ][ j ] and
	// this.transactions[ i ][ j ] will never be changed again after this line.
	this.transactions[ i ][ j ] = transactions[ i ][ j ];
	} else {

	// Previous transactions, leading up to a remove, insert or change
	const remove = transactions[ iMinus1 ][ j ];
	const insert = transactions[ i ][ jMinus1 ];
	const change = transactions[
	orderedNode1.leftmost - 1 < keyRoot1.leftmost ? null : orderedNode1.leftmost - 1
	][
	orderedNode2.leftmost - 1 < keyRoot2.leftmost ? null : orderedNode2.leftmost - 1
	];

	const transaction = getLowestCost(
	remove.length + this.removeCost,
	insert.length + this.insertCost,
	change.length + this.transactions[ i ][ j ].length
	);
	if ( transaction === 0 ) {
	// Record a remove
	transactions[ i ][ j ] = fastSliceAndPush( remove, this.transactionToIndex[ i ][ null ] );
	} else if ( transaction === 1 ) {
	// Record an insert
	transactions[ i ][ j ] = fastSliceAndPush( insert, this.transactionToIndex[ null ][ j ] );
	} else {
	// Record a change
	transactions[ i ][ j ] = fastConcat( change, this.transactions[ i ][ j ] );
	}

	}

	}

	}
	};

	/**
	* Given a set of transactions and the lengths of two trees, find the nodes that
	* correspond.
	*
	* @param {Array} transactions Minimum transactions to get from the first tree to the
	* second tree
	* @param {number} oldTreeLength Number of nodes in the first tree
	* @param {number} newTreeLength Number of nodes in the second tree
	* @return {Object} Corresponding nodes
	*/
	treeDiffer.Differ.prototype.getCorrespondingNodes = function ( transactions, oldTreeLength, newTreeLength ) {
	const oldToNew = {},
	newToOld = {},
	remove = [],
	insert = [],
	change = {},
	ilen = Math.max( oldTreeLength, newTreeLength ),
	jlen = ilen;

	for ( let i = 0; i < transactions.length; i++ ) {
	if ( transactions[ i ][ 0 ] === null ) {
	insert.push( transactions[ i ][ 1 ] );
	} else if ( transactions[ i ][ 1 ] === null ) {
	remove.push( transactions[ i ][ 0 ] );
	} else {
	oldToNew[ transactions[ i ][ 0 ] ] = transactions[ i ][ 1 ];
	newToOld[ transactions[ i ][ 1 ] ] = transactions[ i ][ 0 ];
	change[ transactions[ i ][ 0 ] ] = transactions[ i ][ 1 ];
	}
	}

	const rem = remove.slice();
	const ins = insert.slice();

	remove.sort( ( a, b ) => a - b );
	insert.sort( ( a, b ) => a - b );

	for ( let i = 0, j = 0; i < ilen && j < jlen; i++, j++ ) {
	if ( i === remove[ 0 ] ) {
	// Old node is a remove
	remove.shift();
	j--;
	} else if ( j === insert[ 0 ] ) {
	// New node is an insert
	insert.shift();
	i--;
	} else if ( !( i in oldToNew ) && !( j in newToOld ) ) {
	// Neither is changed, so they must correspond
	// NB Moves don't exist to the tree differ
	oldToNew[ i ] = j;
	newToOld[ j ] = i;
	} else if ( !( i in oldToNew ) ) {
	// Old node is unchanged, new node is changed
	i--;
	} else if ( !( j in newToOld ) ) {
	// New node is unchanged, old node is changed
	j--;
	}
	}

	return {
	oldToNew: oldToNew,
	newToOld: newToOld,
	remove: rem,
	insert: ins,
	change: change
	};
	};

	// eslint-disable-next-line strict
	if ( typeof module !== 'undefined' && module.exports ) {
	module.exports = treeDiffer;
	} else {
	global.treeDiffer = treeDiffer;
	}

	}( this ) );

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