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1/**
2 * A specialized Map class that provides consistent data storage by performing deep cloning of values.
3 *
4 * @template K, V
5 * @extends Map<K, V>
6 */
7export class StructuredCloneMap extends Map {
8 /**
9 * Constructs a new StructuredCloneMap.
10 * @param {object} options - Options for the map
11 * @param {boolean} options.cloneOnGet - Whether to clone the value when getting it from the map
12 * @param {boolean} options.cloneOnSet - Whether to clone the value when setting it in the map
13 */
14 constructor({ cloneOnGet, cloneOnSet } = { cloneOnGet: true, cloneOnSet: true }) {
15 super();
16 this.cloneOnGet = cloneOnGet;
17 this.cloneOnSet = cloneOnSet;
18 }
19
20 /**
21 * Adds a new element with a specified key and value to the Map. If an element with the same key already exists, the element will be updated.
22 *
23 * The set value will always be a deep clone of the provided value to provide consistent data storage.
24 *
25 * @param {K} key - The key to set
26 * @param {V} value - The value to set
27 * @returns {this} The updated map
28 */
29 set(key, value) {
30 if (!this.cloneOnSet) {
31 return super.set(key, value);
32 }
33
34 const clonedValue = structuredClone(value);
35 super.set(key, clonedValue);
36 return this;
37 }
38
39 /**
40 * Returns a specified element from the Map object.
41 * If the value that is associated to the provided key is an object, then you will get a reference to that object and any change made to that object will effectively modify it inside the Map.
42 *
43 * The returned value will always be a deep clone of the cached value.
44 *
45 * @param {K} key - The key to get the value for
46 * @returns {V | undefined} Returns the element associated with the specified key. If no element is associated with the specified key, undefined is returned.
47 */
48 get(key) {
49 if (!this.cloneOnGet) {
50 return super.get(key);
51 }
52
53 const value = super.get(key);
54 return structuredClone(value);
55 }
56}