refactor(frontend): scripts -> utility

packages/frontend/src/utility/clone.ts

@@ -0,0 +1,25 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+// structredCloneが遅いため
+// SEE: http://var.blog.jp/archives/86038606.html
+// あと、Vue RefをIndexedDBに保存しようとしてstructredCloneを使ったらエラーになった
+// https://github.com/misskey-dev/misskey/pull/8098#issuecomment-1114144045
+
+export type Cloneable = string | number | boolean | null | undefined | { [key: string]: Cloneable } | { [key: number]: Cloneable } | { [key: symbol]: Cloneable } | Cloneable[];
+
+export function deepClone<T extends Cloneable>(x: T): T {
+	if (typeof x === 'object') {
+		if (x === null) return x;
+		if (Array.isArray(x)) return x.map(deepClone) as T;
+		const obj = {} as Record<string | number | symbol, Cloneable>;
+		for (const [k, v] of Object.entries(x)) {
+			obj[k] = v === undefined ? undefined : deepClone(v);
+		}
+		return obj as T;
+	} else {
+		return x;
+	}
+}