v3: src/ gets one layout rule and keeps to it — each layer holds one kind of module, and every layer is split into the same domains — the previous pass sorted components into folders but left hooks, helpers and a barrel inside them, kept hooks/, utils/ and contexts/ flat, and still grouped most tests by theme. The rule: components/ holds only components (.tsx), contexts/ holds FooContext.ts + FooProvider.tsx pairs, hooks/ every hook, utils/ every non-React module, pages/ one component per route and nothing else. Each of components/, contexts/, hooks/ and utils/ is split into the same domains — auth, category, chat, comment, dump, editor, feed, form, layout, player, playlist, profile, social, theme, ws — plus shared/ for what belongs to no one domain, so the chat is components/chat, contexts/chat, hooks/chat and utils/chat. components/ui becomes components/shared to match. Out of components/: useApiForm goes to hooks/form, chat's message.ts and time.ts to utils/chat (with chatDraft and chatText, now draft.ts and text.ts), the emoji skin tone to utils/editor, the remembered volume to utils/player; player/icons.tsx is PlayerIcons.tsx. components/form/index.ts is gone: everything is imported from its own file, FormProvider straight from react-hook-form, and expectOk sits beside friendlyFetchError in utils/shared/api.ts (apiError.ts), since pages that have no form used it too. Out of pages/: the index's feed views, tab bar and presence row move to components/feed; HotFeed and NewFeed, identical but for the sort, are one DumpFeed with an order prop, which also takes over MainFeedProps from pages/index/types.ts. App is a named export like everything else. Tests mirror the tree one file per module — test/<layer>/<domain>/<Module>.test.tsx — so the themed files (hooks/misc, data, editor, sync; utils/misc, text, storage, remote, journal; contexts/providers; pages/auth and UserSubpages; layout/Fabs) are split by subject, the setup each piece needs kept and the rest dropped; the floating-button test becomes one test per button, 627 tests now. The README states the rule. No behaviour changes; the catalogues only move their source references.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/test/contexts/category/CategoriesProvider.test.tsx

@@ -0,0 +1,39 @@
+import { describe, expect, test } from "vitest";
+import { act, renderHook, waitFor } from "@testing-library/react";
+import type { ReactNode } from "react";
+import { CategoriesProvider } from "../../../contexts/category/CategoriesProvider.tsx";
+import { useCategories } from "../../../hooks/category/useCategories.ts";
+import { fail, route } from "../../fetch.ts";
+import { makeCategory, wire } from "../../fixtures.ts";
+
+describe("CategoriesProvider", () => {
+  const wrapper = ({ children }: { children: ReactNode }) => (
+    <CategoriesProvider>{children}</CategoriesProvider>
+  );
+
+  test("loads and indexes categories", async () => {
+    const music = makeCategory({ id: "c1", slug: "music" });
+    route("GET /api/categories", () => wire([music]));
+    const { result } = renderHook(useCategories, { wrapper });
+    await waitFor(() => expect(result.current.isLoaded).toBe(true));
+    expect(result.current.byId.get("c1")?.slug).toBe("music");
+    expect(result.current.categories[0].createdAt).toBeInstanceOf(Date);
+  });
+
+  test("refresh refetches", async () => {
+    let list = [makeCategory({ id: "a" })];
+    route("GET /api/categories", () => wire(list));
+    const { result } = renderHook(useCategories, { wrapper });
+    await waitFor(() => expect(result.current.categories).toHaveLength(1));
+    list = [...list, makeCategory({ id: "b" })];
+    await act(() => result.current.refresh());
+    expect(result.current.categories).toHaveLength(2);
+  });
+
+  test("a failure still ends loading", async () => {
+    route("GET /api/categories", () => fail("x", 500));
+    const { result } = renderHook(useCategories, { wrapper });
+    await waitFor(() => expect(result.current.isLoaded).toBe(true));
+    expect(result.current.categories).toEqual([]);
+  });
+});