refactor progress

packages/list_utils/src/ListFormattingCache.tsx

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2026 Fluxer Contributors
+ *
+ * This file is part of Fluxer.
+ *
+ * Fluxer is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Fluxer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Fluxer. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type {ResolvedListFormatterConfig} from '@fluxer/list_utils/src/ListFormattingTypes';
+
+const formatterCache = new Map<string, Intl.ListFormat>();
+
+export function getCachedListFormatter(config: ResolvedListFormatterConfig): Intl.ListFormat {
+	const cacheKey = `${config.locale}:${config.style}:${config.type}`;
+	const cachedFormatter = formatterCache.get(cacheKey);
+	if (cachedFormatter != null) {
+		return cachedFormatter;
+	}
+
+	const formatter = new Intl.ListFormat(config.locale, {
+		style: config.style,
+		type: config.type,
+	});
+
+	formatterCache.set(cacheKey, formatter);
+	return formatter;
+}