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node_modules/symbol-tree/lib/SymbolTreeNode.js

@@ -0,0 +1,54 @@
+'use strict';
+
+module.exports = class SymbolTreeNode {
+        constructor() {
+                this.parent = null;
+                this.previousSibling = null;
+                this.nextSibling = null;
+
+                this.firstChild = null;
+                this.lastChild = null;
+
+                /** This value is incremented anytime a children is added or removed */
+                this.childrenVersion = 0;
+                /** The last child object which has a cached index */
+                this.childIndexCachedUpTo = null;
+
+                /** This value represents the cached node index, as long as
+                 * cachedIndexVersion matches with the childrenVersion of the parent */
+                this.cachedIndex = -1;
+                this.cachedIndexVersion = NaN; // NaN is never equal to anything
+        }
+
+        get isAttached() {
+                return Boolean(this.parent || this.previousSibling || this.nextSibling);
+        }
+
+        get hasChildren() {
+                return Boolean(this.firstChild);
+        }
+
+        childrenChanged() {
+                /* jshint -W016 */
+                // integer wrap around
+                this.childrenVersion = (this.childrenVersion + 1) & 0xFFFFFFFF;
+                this.childIndexCachedUpTo = null;
+        }
+
+        getCachedIndex(parentNode) {
+                // (assumes parentNode is actually the parent)
+                if (this.cachedIndexVersion !== parentNode.childrenVersion) {
+                        this.cachedIndexVersion = NaN;
+                        // cachedIndex is no longer valid
+                        return -1;
+                }
+
+                return this.cachedIndex; // -1 if not cached
+        }
+
+        setCachedIndex(parentNode, index) {
+                // (assumes parentNode is actually the parent)
+                this.cachedIndexVersion = parentNode.childrenVersion;
+                this.cachedIndex = index;
+        }
+};

node_modules/symbol-tree/lib/TreeIterator.js

@@ -0,0 +1,69 @@
+'use strict';
+
+const TREE = Symbol();
+const ROOT = Symbol();
+const NEXT = Symbol();
+const ITERATE_FUNC = Symbol();
+
+class TreeIterator {
+        constructor(tree, root, firstResult, iterateFunction) {
+                this[TREE] = tree;
+                this[ROOT] = root;
+                this[NEXT] = firstResult;
+                this[ITERATE_FUNC] = iterateFunction;
+        }
+
+        next() {
+                const tree = this[TREE];
+                const iterateFunc = this[ITERATE_FUNC];
+                const root = this[ROOT];
+
+                if (!this[NEXT]) {
+                        return {
+                                done: true,
+                                value: root,
+                        };
+                }
+
+                const value = this[NEXT];
+
+                if (iterateFunc === 1) {
+                        this[NEXT] = tree._node(value).previousSibling;
+                }
+                else if (iterateFunc === 2) {
+                        this[NEXT] = tree._node(value).nextSibling;
+                }
+                else if (iterateFunc === 3) {
+                        this[NEXT] = tree._node(value).parent;
+                }
+                else if (iterateFunc === 4) {
+                        this[NEXT] = tree.preceding(value, {root: root});
+                }
+                else /* if (iterateFunc === 5)*/ {
+                        this[NEXT] = tree.following(value, {root: root});
+                }
+
+                return {
+                        done: false,
+                        value: value,
+                };
+        }
+}
+
+Object.defineProperty(TreeIterator.prototype, Symbol.iterator, {
+        value: function() {
+                return this;
+        },
+        writable: false,
+});
+
+TreeIterator.PREV = 1;
+TreeIterator.NEXT = 2;
+TreeIterator.PARENT = 3;
+TreeIterator.PRECEDING = 4;
+TreeIterator.FOLLOWING = 5;
+
+Object.freeze(TreeIterator);
+Object.freeze(TreeIterator.prototype);
+
+module.exports = TreeIterator;

node_modules/symbol-tree/lib/TreePosition.js

@@ -0,0 +1,11 @@
+'use strict';
+
+/* eslint-disable sort-keys */
+module.exports = Object.freeze({
+        // same as DOM DOCUMENT_POSITION_
+        DISCONNECTED: 1,
+        PRECEDING: 2,
+        FOLLOWING: 4,
+        CONTAINS: 8,
+        CONTAINED_BY: 16,
+});