fix(event): remove all any casts — typed authenticate, user.id, and Prisma error narrowing

apps/backend/src/__tests__/event.test.ts

@@ -1,8 +1,10 @@
+import { type PrismaClient, Prisma } from '@prisma/client';
+import Fastify, { type FastifyInstance } from 'fastify';
 import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
-import Fastify, { FastifyInstance } from 'fastify';
-import { PrismaClient } from '@prisma/client';
+
 import { eventRoutes } from '../routes/event';
 
+
 // ─── Shared mock data ────────────────────────────────────────────────────────
 
 const MOCK_USER_ID = 'user-uuid-001';
@@ -64,7 +66,7 @@
 //
 // This mirrors the real app setup without touching a real DB or real JWT keys.
 
-let mockJwtVerify = vi.fn();
+const mockJwtVerify = vi.fn();
 
 async function buildApp(): Promise<FastifyInstance> {
   const app = Fastify({ logger: false });
@@ -97,7 +99,7 @@
   app: FastifyInstance,
   body: Record<string, unknown>,
   authenticated = true,
-) {
+): Promise<Awaited<ReturnType<FastifyInstance['inject']>>> {
   return app.inject({
     method: 'POST',
     url: '/api/events',
@@ -140,7 +142,7 @@
 
       const res = await createEvent(app, validBody);
 
       expect(res.statusCode).toBe(201);
       const body = res.json();
       expect(body.slug).toBe('devcard-conf-2025');
       expect(body.organizerId).toBe(MOCK_USER_ID);
@@ -159,40 +161,40 @@
 
       const res = await createEvent(app, validBody, false);
 
       expect(res.statusCode).toBe(401);
       expect(res.json()).toMatchObject({ error: 'Unauthorized' });
     });
 
     it('400 — rejects missing required fields (no dates, no location)', async () => {
       const res = await createEvent(app, { name: 'Hello World' }); // missing dates + location
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects missing location', async () => {
       const { location: _omit, ...bodyWithoutLocation } = validBody;
       const res = await createEvent(app, bodyWithoutLocation);
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects location shorter than 2 characters', async () => {
       const res = await createEvent(app, { ...validBody, location: 'A' });
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects location longer than 100 characters', async () => {
       const res = await createEvent(app, { ...validBody, location: 'A'.repeat(101) });
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects event name shorter than 3 characters', async () => {
       const res = await createEvent(app, { ...validBody, name: 'Hi' });
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects event name longer than 100 characters', async () => {
       const longName = 'A'.repeat(101);
       const res = await createEvent(app, { ...validBody, name: longName });
       expect(res.statusCode).toBe(400);
     });
 
     it('400 — rejects invalid date format', async () => {
@@ -200,7 +202,7 @@
         ...validBody,
         startDate: 'not-a-date',
       });
       expect(res.statusCode).toBe(400);
     });
 
     it('201 — generates a unique slug when the first candidate is taken', async () => {
@@ -216,7 +218,7 @@
 
       const res = await createEvent(app, validBody);
 
       expect(res.statusCode).toBe(201);
       // create was eventually called with a slug different from the base one
       const createdSlug: string = prismaMock.event.create.mock.calls[0][0].data.slug;
       expect(createdSlug).toMatch(/^devcard-conf-2025-[a-z0-9]+$/);
@@ -355,9 +357,10 @@
     it('409 — returns 409 when user already joined the event', async () => {
       prismaMock.event.findUnique.mockResolvedValue(MOCK_EVENT);
       // Prisma unique constraint error
-      const uniqueError = Object.assign(new Error('Unique constraint'), {
-        code: 'P2002',
-      });
+      const uniqueError = new Prisma.PrismaClientKnownRequestError(
+          'Unique constraint failed',
+          { code: 'P2002', clientVersion: '6.0.0' },
+      );
       prismaMock.eventAttendee.create.mockRejectedValue(uniqueError);
 
       const res = await app.inject({
@@ -440,9 +443,10 @@
     it('404 — returns 404 when user was never an attendee (P2025)', async () => {
       prismaMock.event.findUnique.mockResolvedValue(MOCK_EVENT);
       // Prisma record-not-found error
-      const notFoundError = Object.assign(new Error('Record not found'), {
-        code: 'P2025',
-      });
+      const notFoundError = new Prisma.PrismaClientKnownRequestError(
+          'Record not found',
+          { code: 'P2025', clientVersion: '6.0.0' },
+      );
       prismaMock.eventAttendee.delete.mockRejectedValue(notFoundError);
 
       const res = await app.inject({
@@ -476,7 +480,13 @@
     /** Builds a raw EventAttendee row as Prisma returns it (with nested user) */
     function makeAttendeeRow(
       profile: typeof MOCK_USER_PROFILE | typeof MOCK_OTHER_USER_PROFILE,
-    ) {
+    ): {
+      id: string;
+      userId: string;
+      eventId: string;
+      joinedAt: Date;
+      user: typeof profile;
+    } {
       return {
         id: `attendee-${profile.id}`,
         userId: profile.id,