bugfix: don't JSON.parse empty 200/201 bodies (0.19.1)

$(addMangaToCollection crashed when the backend returned 201/200 with no body — the shared client only short-circuited 204. Now any empty body returns undefined.)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/Cargo.lock

@@ -1033,7 +1033,7 @@ checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
 
 [[package]]
 name = "mangalord"
-version = "0.19.0"
+version = "0.19.1"
 dependencies = [
  "anyhow",
  "argon2",

backend/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mangalord"
-version = "0.19.0"
+version = "0.19.1"
 edition = "2021"
 
 [lib]

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.19.0",
+  "version": "0.19.1",
   "private": true,
   "type": "module",
   "scripts": {

frontend/src/lib/api/client.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect, vi, beforeEach, afterEach, type MockInstance } from 'vitest';
-import { ApiError } from './client';
+import { ApiError, request } from './client';
 import { getManga } from './mangas';
 
 describe('request error envelope parsing', () => {
@@ -48,6 +48,20 @@ describe('request error envelope parsing', () => {
         expect(err.code).toBe('http_error');
     });
 
+    it('treats empty 200/201 bodies as undefined (no JSON.parse crash)', async () => {
+        // Regression: addMangaToCollection is typed `void` and the
+        // backend returns 201 (created) / 200 (already there) with
+        // no body. Without the empty-body short-circuit, `res.json()`
+        // would throw `JSON.parse: unexpected end of data`.
+        fetchSpy.mockResolvedValueOnce(new Response(null, { status: 201 }));
+        const created = await request<void>('/v1/whatever', { method: 'POST' });
+        expect(created).toBeUndefined();
+
+        fetchSpy.mockResolvedValueOnce(new Response(null, { status: 200 }));
+        const ok200 = await request<void>('/v1/whatever', { method: 'POST' });
+        expect(ok200).toBeUndefined();
+    });
+
     it('falls back to http_error code when JSON has no error envelope', async () => {
         fetchSpy.mockResolvedValueOnce(
             new Response(JSON.stringify({ message: 'oops' }), {

frontend/src/lib/api/client.ts

@@ -56,10 +56,18 @@ export async function request<T>(path: string, init?: RequestInit): Promise<T> {
         }
         throw new ApiError(res.status, code, message);
     }
+    // Any empty body (not just 204) returns undefined — the manga-add
+    // endpoint, for instance, signals create-vs-already-present via
+    // 201/200 with no body, and callers typed `request<void>` would
+    // otherwise blow up on `res.json()` parsing an empty string.
     if (res.status === 204) {
         return undefined as T;
     }
-    return (await res.json()) as T;
+    const text = await res.text();
+    if (!text) {
+        return undefined as T;
+    }
+    return JSON.parse(text) as T;
 }
 
 export type Manga = {