/// <summary>
        /// Flag indicating whether the node's PathItems dictionary has operations
        /// under a given label.
        /// </summary>
        /// <param name="label">The name of the key for the target operations
        /// in the node's PathItems dictionary.</param>
        /// <returns>true or false.</returns>
        public bool HasOperations(string label)
        {
            Utils.CheckArgumentNullOrEmpty(label, nameof(label));

            if (!(PathItems?.ContainsKey(label) ?? false))
            {
                return(false);
            }

            return(PathItems[label].Operations?.Any() ?? false);
        }
        /// <summary>
        /// Assembles the constituent properties of an <see cref="OpenApiUrlTreeNode"/> node.
        /// </summary>
        /// <param name="segments">IEnumerable subdirectories of a relative path.</param>
        /// <param name="pathItem">Path Item object that describes the operations available on an OpenAPI path.</param>
        /// <param name="label">A name tag for labelling the <see cref="OpenApiUrlTreeNode"/> node.</param>
        /// <param name="currentPath">The relative path of a node.</param>
        /// <returns>An <see cref="OpenApiUrlTreeNode"/> node with all constituent properties assembled.</returns>
        private OpenApiUrlTreeNode Attach(IEnumerable <string> segments,
                                          OpenApiPathItem pathItem,
                                          string label,
                                          string currentPath)
        {
            var segment = segments.FirstOrDefault();

            if (string.IsNullOrEmpty(segment))
            {
                if (PathItems.ContainsKey(label))
                {
                    throw new ArgumentException("A duplicate label already exists for this node.", nameof(label));
                }

                Path = currentPath;
                PathItems.Add(label, pathItem);
                return(this);
            }

            // If the child segment has already been defined, then insert into it
            if (Children.ContainsKey(segment))
            {
                var newPath = currentPath + PathSeparator + segment;

                return(Children[segment].Attach(segments: segments.Skip(1),
                                                pathItem: pathItem,
                                                label: label,
                                                currentPath: newPath));
            }
            else
            {
                var newPath = currentPath + PathSeparator + segment;

                var node = new OpenApiUrlTreeNode(segment)
                {
                    Path = newPath
                };

                Children[segment] = node;

                return(node.Attach(segments: segments.Skip(1),
                                   pathItem: pathItem,
                                   label: label,
                                   currentPath: newPath));
            }
        }