throw errors on failure

packages/playground/storage/src/lib/filesystems.ts

@@ -394,29 +394,24 @@ export class OpfsFilesystemBackend implements WritableFilesystemBackend {
 
 	/**
 	 * Create a backend for a specific path in OPFS.
-	 * The path will be created if it doesn't exist.
+	 * The path will be created if `create` is true.
+	 * @throws Error if OPFS is not available or path doesn't exist (when create=false)
 	 */
 	static async fromPath(
 		pathSegments: string[],
 		create = false
-	): Promise<OpfsFilesystemBackend | null> {
+	): Promise<OpfsFilesystemBackend> {
 		if (typeof navigator === 'undefined') {
-			return null;
+			throw new Error('OPFS not available: navigator is undefined');
 		}
 		if (!navigator.storage || !navigator.storage.getDirectory) {
-			return null;
+			throw new Error('OPFS not available: storage API not supported');
 		}
-		try {
-			let handle = await navigator.storage.getDirectory();
-			for (const segment of pathSegments) {
-				handle = await handle.getDirectoryHandle(segment, {
-					create,
-				});
-			}
-			return new OpfsFilesystemBackend(handle);
-		} catch {
-			return null;
+		let handle = await navigator.storage.getDirectory();
+		for (const segment of pathSegments) {
+			handle = await handle.getDirectoryHandle(segment, { create });
 		}
+		return new OpfsFilesystemBackend(handle);
 	}
 
 	async clear(): Promise<void> {

packages/playground/website/src/components/blueprint-editor/writable-opfs-filesystem.ts

@@ -24,13 +24,14 @@ export class OpfsFilesystemBackend extends BaseOpfsFilesystemBackend {
 	 * Check if there's a saved blueprint bundle in the default location.
 	 */
 	static async hasSavedBundle(): Promise<boolean> {
-		const backend =
-			await BaseOpfsFilesystemBackend.fromPath(OPFS_BASE_PATH);
-		if (!backend) {
+		try {
+			const backend =
+				await BaseOpfsFilesystemBackend.fromPath(OPFS_BASE_PATH);
+			const files = await backend.listFiles('/');
+			return files.length > 0;
+		} catch {
 			return false;
 		}
-		const files = await backend.listFiles('/');
-		return files.length > 0;
 	}
 
 	/**
@@ -42,9 +43,6 @@ export class OpfsFilesystemBackend extends BaseOpfsFilesystemBackend {
 			OPFS_BASE_PATH,
 			true
 		);
-		if (!backend) {
-			throw new Error('OPFS not available');
-		}
 		// Cast to the extended type since we know it's compatible
 		return backend as unknown as OpfsFilesystemBackend;
 	}

packages/playground/website/src/lib/state/opfs/opfs-blueprint-bundle-storage.ts

@@ -27,14 +27,15 @@ function getBundlePathSegments(siteSlug: string): string[] {
  * Check if a site has a persisted blueprint bundle.
  */
 export async function hasBlueprintBundle(siteSlug: string): Promise<boolean> {
-	const backend = await OpfsFilesystemBackend.fromPath(
-		getBundlePathSegments(siteSlug)
-	);
-	if (!backend) {
+	try {
+		const backend = await OpfsFilesystemBackend.fromPath(
+			getBundlePathSegments(siteSlug)
+		);
+		const files = await backend.listFiles('/');
+		return files.length > 0;
+	} catch {
 		return false;
 	}
-	const files = await backend.listFiles('/');
-	return files.length > 0;
 }
 
 /**
@@ -48,21 +49,20 @@ export async function persistBlueprintBundle(
 		getBundlePathSegments(siteSlug),
 		true
 	);
-	if (!destination) {
-		throw new Error('OPFS not available');
-	}
 	await copyFilesystem(source, destination);
 }
 
 /**
  * Delete a site's blueprint bundle.
  */
 export async function deleteBlueprintBundle(siteSlug: string): Promise<void> {
-	const backend = await OpfsFilesystemBackend.fromPath(
-		getBundlePathSegments(siteSlug)
-	);
-	if (backend) {
+	try {
+		const backend = await OpfsFilesystemBackend.fromPath(
+			getBundlePathSegments(siteSlug)
+		);
 		await backend.clear();
+	} catch {
+		// Bundle doesn't exist, nothing to delete
 	}
 }
 
@@ -73,11 +73,5 @@ export async function deleteBlueprintBundle(siteSlug: string): Promise<void> {
 export async function loadPersistedBlueprintBundle(
 	siteSlug: string
 ): Promise<OpfsFilesystemBackend> {
-	const backend = await OpfsFilesystemBackend.fromPath(
-		getBundlePathSegments(siteSlug)
-	);
-	if (!backend) {
-		throw new Error(`Blueprint bundle not found for site: ${siteSlug}`);
-	}
-	return backend;
+	return OpfsFilesystemBackend.fromPath(getBundlePathSegments(siteSlug));
 }