Use Set to mark icons as missing

components/svg-framework/src/scanner/index.ts

@@ -70,7 +70,7 @@ export function scanDOM(rootNode?: ObservedNode, addTempNode = false): void {
 			};
 		}
 
-		if (storage.missing[name]) {
+		if (storage.missing.has(name)) {
 			return {
 				status: 'missing',
 			};

packages/core/src/api/callbacks.ts

@@ -109,7 +109,7 @@ export function updateCallbacks(provider: string, prefix: string): void {
 							prefix,
 							name,
 						});
-					} else if (storage.missing[name] !== void 0) {
+					} else if (storage.missing.has(name)) {
 						// Missing
 						icons.missing.push({
 							provider,

packages/core/src/api/icons.ts

@@ -186,9 +186,8 @@ function loadNewIcons(provider: string, prefix: string, icons: string[]): void {
 						}
 
 						// Not found: mark as missing
-						const t = Date.now();
 						item.icons.forEach((name) => {
-							storage.missing[name] = t;
+							storage.missing.add(name);
 						});
 					} else {
 						// Add icons to storage

packages/core/src/icon/sort.ts

@@ -72,7 +72,7 @@ export function sortIcons(icons: IconifyIconName[]): SortedIcons {
 		let list;
 		if (localStorage.icons[name] !== void 0) {
 			list = result.loaded;
-		} else if (prefix === '' || localStorage.missing[name] !== void 0) {
+		} else if (prefix === '' || localStorage.missing.has(name)) {
 			// Mark icons without prefix as missing because they cannot be loaded from API
 			list = result.missing;
 		} else {

packages/core/src/storage/functions.ts

@@ -69,7 +69,8 @@ export function getIconData(
 	const storage = getStorage(icon.provider, icon.prefix);
 	const iconName = icon.name;
 	return (
-		storage.icons[iconName] || (storage.missing[iconName] ? null : void 0)
+		storage.icons[iconName] ||
+		(storage.missing.has(iconName) ? null : void 0)
 	);
 }
 

packages/core/src/storage/storage.ts

@@ -7,16 +7,21 @@ import { quicklyValidateIconSet } from '@iconify/utils/lib/icon-set/validate-bas
 /**
  * List of icons
  */
-type IconRecords = Record<string, FullIconifyIcon | null>;
+type IconRecords = Record<string, FullIconifyIcon>;
 
 /**
  * Storage type
  */
 export interface IconStorage {
+	// Provider and prefix
 	provider: string;
 	prefix: string;
+
+	// List of available icons
 	icons: IconRecords;
-	missing: Record<string, number>;
+
+	// List of missing icons
+	missing: Set<string>;
 }
 
 /**
@@ -35,7 +40,7 @@ export function newStorage(provider: string, prefix: string): IconStorage {
 		provider,
 		prefix,
 		icons: Object.create(null) as IconStorage['icons'],
-		missing: Object.create(null) as IconStorage['missing'],
+		missing: new Set(),
 	};
 }
 
@@ -63,12 +68,11 @@ export function addIconSet(storage: IconStorage, data: IconifyJSON): string[] {
 		return [];
 	}
 
-	const t = Date.now();
 	return parseIconSet(data, (name, icon: FullIconifyIcon | null) => {
 		if (icon) {
 			storage.icons[name] = icon;
 		} else {
-			storage.missing[name] = t;
+			storage.missing.add(name);
 		}
 	});
 }
@@ -100,7 +104,7 @@ export function addIconToStorage(
  * Check if icon exists
  */
 export function iconExists(storage: IconStorage, name: string): boolean {
-	return storage.icons[name] !== void 0;
+	return !!storage.icons[name];
 }
 
 /**

packages/core/tests/storage/storage-test.ts

@@ -37,7 +37,7 @@ describe('Testing storage', () => {
 		});
 
 		// Mark 'not-really-missing' as missing
-		storage.missing['not-really-missing'] = Date.now();
+		storage.missing.add('not-really-missing');
 
 		// Add invalid icon
 		addIconToStorage(storage, 'invalid', {} as unknown as IconifyIcon);