55 lines
1.2 KiB
JavaScript
55 lines
1.2 KiB
JavaScript
// @ts-check
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/**
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* A node path is an array of indices that can traverse a Node tree.
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*
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* For example, given the following tree:
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*
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* ```javascript
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* {
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* name: "top",
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* children: [
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* { name: "first" },
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* { name: "second", children: [{ name: "grandchild" }] },
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* ],
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* }
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* ```
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*
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* `[]` is "top", `[0]` is "first", `[1]` is "second", and `[1, 0]` is "grandchild".
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*
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* @typedef {number[]} NodePath
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*/
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/**
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* @param {unknown} value
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* @returns {null | NodePath} The parsed node path, or null if invalid.
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*/
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export const parse = (value) => {
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if (typeof value !== "string") return null;
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if (!value) return [];
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return value.split(",").map((str) => {
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const result = parseInt(str, 10);
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if (Number.isFinite(result)) return result;
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throw new Error(`Invalid node path: ${value}`);
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});
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};
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/**
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* @param {NodePath} a
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* @param {NodePath} b
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* @returns {boolean}
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*/
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export const isEqualTo = (a, b) => a.length === b.length && isSupersetOf(a, b);
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/**
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* @param {NodePath} smaller
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* @param {NodePath} bigger
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* @returns {boolean}
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*/
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export const isSupersetOf = (smaller, bigger) => {
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for (let i = 0; i < smaller.length; i++) {
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if (smaller[i] !== bigger[i]) return false;
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}
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return true;
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};
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