"use strict";
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const DOMException = require("domexception");
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const { filter, FILTER_ACCEPT, FILTER_REJECT, FILTER_SKIP } = require("./helpers");
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const FIRST = false;
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const LAST = true;
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const NEXT = false;
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const PREVIOUS = true;
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exports.implementation = class TreeWalkerImpl {
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constructor(args, privateData) {
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this._active = false;
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this.root = privateData.root;
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this.whatToShow = privateData.whatToShow;
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this.filter = privateData.filter;
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this.currentNode = this.root;
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}
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get currentNode() {
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return this._currentNode;
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}
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set currentNode(node) {
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if (node === null) {
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throw new DOMException("Cannot set currentNode to null", "NotSupportedError");
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}
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this._currentNode = node;
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}
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parentNode() {
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let node = this._currentNode;
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while (node !== null && node !== this.root) {
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node = node.parentNode;
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if (node !== null && filter(this, node) === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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}
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return null;
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}
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firstChild() {
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return this._traverseChildren(FIRST);
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}
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lastChild() {
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return this._traverseChildren(LAST);
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}
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previousSibling() {
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return this._traverseSiblings(PREVIOUS);
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}
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nextSibling() {
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return this._traverseSiblings(NEXT);
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}
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previousNode() {
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let node = this._currentNode;
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while (node !== this.root) {
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let sibling = node.previousSibling;
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while (sibling !== null) {
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node = sibling;
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let result = filter(this, node);
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while (result !== FILTER_REJECT && node.hasChildNodes()) {
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node = node.lastChild;
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result = filter(this, node);
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}
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if (result === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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sibling = node.previousSibling;
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}
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if (node === this.root || node.parentNode === null) {
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return null;
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}
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node = node.parentNode;
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if (filter(this, node) === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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}
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return null;
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}
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nextNode() {
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let node = this._currentNode;
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let result = FILTER_ACCEPT;
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for (;;) {
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while (result !== FILTER_REJECT && node.hasChildNodes()) {
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node = node.firstChild;
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result = filter(this, node);
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if (result === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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}
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do {
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if (node === this.root) {
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return null;
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}
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const sibling = node.nextSibling;
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if (sibling !== null) {
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node = sibling;
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break;
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}
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node = node.parentNode;
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} while (node !== null);
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if (node === null) {
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return null;
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}
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result = filter(this, node);
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if (result === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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}
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}
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_traverseChildren(type) {
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let node = this._currentNode;
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node = type === FIRST ? node.firstChild : node.lastChild;
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if (node === null) {
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return null;
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}
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main: for (;;) {
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const result = filter(this, node);
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if (result === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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if (result === FILTER_SKIP) {
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const child = type === FIRST ? node.firstChild : node.lastChild;
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if (child !== null) {
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node = child;
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continue;
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}
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}
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for (;;) {
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const sibling = type === FIRST ? node.nextSibling : node.previousSibling;
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if (sibling !== null) {
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node = sibling;
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continue main;
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}
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const parent = node.parentNode;
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if (parent === null || parent === this.root || parent === this._currentNode) {
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return null;
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}
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node = parent;
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}
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}
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}
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_traverseSiblings(type) {
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let node = this._currentNode;
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if (node === this.root) {
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return null;
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}
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for (;;) {
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let sibling = type === NEXT ? node.nextSibling : node.previousSibling;
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while (sibling !== null) {
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node = sibling;
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const result = filter(this, node);
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if (result === FILTER_ACCEPT) {
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return (this._currentNode = node);
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}
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sibling = type === NEXT ? node.firstChild : node.lastChild;
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if (result === FILTER_REJECT || sibling === null) {
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sibling = type === NEXT ? node.nextSibling : node.previousSibling;
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}
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}
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node = node.parentNode;
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if (node === null || node === this.root) {
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return null;
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}
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if (filter(this, node) === FILTER_ACCEPT) {
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return null;
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}
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}
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}
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};
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