feat(FR-2609): Vitest migration for react/ (100% pass, 856/856 tests) (#6874)

Resolves #6812(FR-2609)

## Summary

Migrates `react/`'s test suite from Jest to Vitest. **856/856 tests passing** under Vitest.

(Commit title still reads `96.9% pass rate, 822/848 tests` — that was the baseline before the last-mile fixes landed in-tree via `gt modify`. Current state is 100%; see test-plan counts below.)

### New files
- `react/vitest.config.ts` — reuses `@vitejs/plugin-react` + `babel-plugin-react-compiler` + `babel-plugin-relay` so tests and the running app exercise identical transformed code.
- `react/__test__/vitest.jest-compat.ts` — exposes `vi` as `jest` globally, so existing `jest.fn()` / `jest.spyOn()` calls in test files continue to work without a sweeping rename.

### Vitest 4 pitfalls fixed inline
- **`process.env.NODE_ENV` is non-configurable** in Node 20+. Replaced `Object.defineProperty(process.env, 'NODE_ENV', ...)` with `vi.stubEnv('NODE_ENV', ...)` + `vi.unstubAllEnvs()` in `customThemeConfig.test.ts`.
- **Default-export mock shape**: `vi.mock(path, () => Component)` must return `{ default: Component }` for files imported via `import X from ...`. Fixed in `MyResourceWithinResourceGroup.test.tsx`.
- **Arrow-function `mockImplementation` called with `new`**: `new TabCount()` throws because arrow functions aren't constructors. Swapped all `MockedTabCount.mockImplementation(() => ({...}))` to `function(this: any) {...}` in `useLoginOrchestration.test.ts`.
- **Factory-created vi.fn() mock history** isn't cleared by `vi.restoreAllMocks()` (that only touches `spyOn` spies). Added `vi.clearAllMocks()` in `afterEach` to prevent call-count leakage across tests.

## Test plan

- [x] `pnpm --prefix ./react run vitest` → 856/856 pass
- [x] Same React Compiler / Relay transforms as prod build (`'use memo'` optimisations active in tests)
- [x] `scripts/verify.sh` passes for Lint + Format + Relay checks

## Stack

Builds on FR-2608. The broader Jest → Vitest cutover continues in the next PR (BUI + root `/src`).

Author: nowgnuesLee

pnpm-lock.yaml

@@ -77,9 +77,51 @@ Fix:
 
 (Each of these gets its own sub-issue under FR-2605.)
 
-- Jest → Vitest migration (FR-2609)
 - CI pipeline updates (FR-2611)
 
+## Vitest migration (react/ only) — complete (FR-2609)
+
+`pnpm --prefix ./react run vitest` now passes **856/856 tests** across the migrated suite. The Vitest-semantic differences from Jest noted below have been resolved as part of this PR, so this note no longer implies outstanding failures.
+
+### What was added
+
+- `react/vitest.config.ts` — dedicated Vitest config, separate from `vite.config.ts`. Shares the transform pipeline (`@vitejs/plugin-react` + babel-plugin-relay with per-directory `artifactDirectory` + babel-plugin-react-compiler) so tests exercise the same transforms as dev/prod.
+- `react/__test__/vitest.jest-compat.ts` — a setup file that aliases `globalThis.jest = vi` so legacy `jest.fn()` / `jest.clearAllMocks()` call sites continue to work. Migration aid only; new tests should use `vi.*` directly.
+- `vitest` / `vitest:watch` scripts in `react/package.json`.
+
+### Bulk migrations applied
+
+Mechanical `jest.` → `vi.` rewrites across 39 test files (perl one-liner in the commit message):
+
+- `jest.mock|fn|spyOn|clearAllMocks|resetAllMocks|restoreAllMocks|useFakeTimers|useRealTimers|advanceTimersByTime|runOnlyPendingTimers|runAllTimers|doMock` → `vi.*`
+- `jest.Mock` (type cast) → `Mock`, with `import type { Mock } from 'vitest'` added
+- Removed `@jest/globals` import lines (Vitest's `globals: true` provides them)
+
+Without this, Vitest's `vi.mock` hoisting does NOT apply to `jest.mock(...)` calls (Vitest only recognises literal `vi.mock` for hoisting). The rewrites restore mock correctness across 14+ files.
+
+### Module resolution
+
+- `src/` baseUrl via regex alias `{ find: /^src\//, replacement: reactSrc + '/' }`.
+- `backend.ai-ui/*`, `backend.ai-client-esm` mapped to same mocks Jest used.
+- `.svg` plain imports → `__test__/svg.mock.js`; `.svg?react` → `vite-plugin-svgr`.
+- `.css` / `.css?raw` → `__test__/rawCss.mock.js` (regex anchored with `^.+` so the entire specifier is replaced; array-form aliases replace the matched portion).
+
+### Vitest-semantic differences from Jest (resolved in this PR)
+
+- `react/src/helper/customThemeConfig.test.ts` — was using `Object.defineProperty(process.env, 'NODE_ENV', ...)` to toggle dev/prod; Vitest's `process.env.NODE_ENV` has an immutable descriptor. Migrated to `vi.stubEnv('NODE_ENV', ...)` + `vi.unstubAllEnvs()` in `afterEach`, plus `vi.restoreAllMocks()` between nested describes to avoid event-dispatcher accumulation.
+- `react/src/components/MyResourceWithinResourceGroup.test.tsx` and `react/src/hooks/useResourceLimitAndRemaining.test.ts` — bare `vi.mock(path)` without a factory does not produce a `default` export for ESM under Vitest. Fixed by passing an explicit `() => ({ default: vi.fn() })` factory.
+
+### Performance
+
+- Vitest run: ~20s wall clock for 848 tests (transform 71s, tests 6s — tests themselves are very fast; the time is transform + import cost, paid only once per file).
+- Jest equivalent on the same tree has not been measured in this session; prior expectation was 60-120s. Confidence level: "materially faster" but exact multiplier needs a controlled benchmark.
+
+### Still open
+
+- BUI (`packages/backend.ai-ui`) Jest → Vitest migration
+- Root `/src` Jest → Vitest migration
+- `transformIgnorePatterns` regex in existing `react/jest.config.cjs` can be deleted once the Jest pipeline is fully retired.
+
 ## Production `vite build` + Workbox PWA — landed (FR-2608)
 
 `pnpm --prefix ./react run vite:build` now produces a working web build with a generated service worker. Output goes to `react/build/`, same directory the craco pipeline uses.

react/VITE_POC_NOTES.md

@@ -0,0 +1,27 @@
+// Vitest ↔ Jest compatibility shim for the FR-2609 migration.
+//
+// Instead of renaming every `jest.fn()`, `jest.mock()`, `jest.spyOn()` etc.
+// call across ~39 test files in react/src, we expose `vi` under the name
+// `jest` so existing tests run as-is. Newly authored tests should use `vi.*`
+// directly — this shim is a migration aid, not a long-term convention.
+//
+// Vitest's `vi` object is mostly a drop-in for Jest:
+//   - `jest.fn` → `vi.fn`
+//   - `jest.mock` → `vi.mock` (behaviour is equivalent; hoisting rules differ
+//     in corner cases around using captured variables in the factory)
+//   - `jest.spyOn` → `vi.spyOn`
+//   - `jest.useFakeTimers` / `jest.useRealTimers` → `vi.useFakeTimers` /
+//     `vi.useRealTimers` (defaults differ slightly; see vitest docs)
+//   - `jest.resetAllMocks` / `jest.clearAllMocks` / `jest.restoreAllMocks` →
+//     `vi.resetAllMocks` / `vi.clearAllMocks` / `vi.restoreAllMocks`
+//
+// For APIs without a direct `vi` equivalent (e.g. `jest.requireActual`),
+// the offending call will throw at test time and we fix it inline there.
+import { vi } from 'vitest';
+
+// `globals: true` in vitest.config.ts already exposes `vi` as a global.
+// The line below ALSO exposes it as `jest` so prior Jest-style calls still
+// resolve. Both globals co-exist; no name collision since `jest` is not
+// otherwise defined under Vitest.
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+(globalThis as any).jest = vi;

react/__test__/vitest.jest-compat.ts

@@ -90,6 +90,8 @@
     "start": "NODE_OPTIONS='--max-old-space-size=4096' craco start",
     "vite:dev": "vite",
     "vite:build": "vite build",
+    "vitest": "vitest run",
+    "vitest:watch": "vitest",
     "build": "pnpm run build:only && cp -r ./build/* ../build/web/",
     "build:only": "NODE_OPTIONS='--max-old-space-size=4096' pnpm run relay && NODE_OPTIONS='--max-old-space-size=4096' craco build",
     "test": "NODE_OPTIONS='$NODE_OPTIONS --no-deprecation --experimental-vm-modules' jest",
@@ -155,6 +157,7 @@
     "jest": "catalog:",
     "jest-canvas-mock": "^2.5.2",
     "jest-environment-jsdom": "catalog:",
+    "jsdom": "^29.0.2",
     "nodemon": "^3.1.14",
     "prop-types": "^15.8.1",
     "react-dev-utils": "^12.0.1",
@@ -169,6 +172,7 @@
     "vite-plugin-node-polyfills": "^0.24.0",
     "vite-plugin-pwa": "^1.2.0",
     "vite-plugin-svgr": "^4.5.0",
+    "vitest": "^4.1.4",
     "webpack": "catalog:",
     "workbox-webpack-plugin": "^7.4.0"
   }

react/package.json

@@ -11,13 +11,13 @@ import { render, screen } from '@testing-library/react';
 import React from 'react';
 
 // Mock all the required hooks and dependencies
-jest.mock('react-i18next', () => ({
+vi.mock('react-i18next', () => ({
   useTranslation: () => ({
     t: (key: string) => key,
   }),
 }));
 
-jest.mock('antd', () => ({
+vi.mock('antd', () => ({
   Segmented: ({ children }: any) => (
     <div data-testid="segmented">{children}</div>
   ),
@@ -30,11 +30,11 @@ jest.mock('antd', () => ({
   },
 }));
 
-jest.mock('ahooks', () => ({
-  useControllableValue: () => ['free', jest.fn()],
+vi.mock('ahooks', () => ({
+  useControllableValue: () => ['free', vi.fn()],
 }));
 
-jest.mock('../hooks/useCurrentProject', () => ({
+vi.mock('../hooks/useCurrentProject', () => ({
   useCurrentProjectValue: () => ({ name: 'test-project' }),
   useCurrentResourceGroupValue: () => 'default',
 }));
@@ -117,8 +117,8 @@ const mockDataScenarios = {
   },
 };
 
-jest.mock('../hooks/useResourceLimitAndRemaining', () => ({
-  useResourceLimitAndRemaining: jest.fn(() => [
+vi.mock('../hooks/useResourceLimitAndRemaining', () => ({
+  useResourceLimitAndRemaining: vi.fn(() => [
     {
       resourceGroupResourceSize: { cpu: 0, mem: '0 GiB', accelerators: {} },
       resourceLimits: { accelerators: {} },
@@ -130,12 +130,12 @@ jest.mock('../hooks/useResourceLimitAndRemaining', () => ({
       checkPresetInfo: mockDataScenarios.normal as any,
     },
     {
-      refetch: jest.fn(),
+      refetch: vi.fn(),
     },
   ]),
 }));
 
-jest.mock('backend.ai-ui', () => {
+vi.mock('backend.ai-ui', () => {
   const isoDate = new Date().toISOString();
   return {
     useResourceSlotsDetails: () => ({
@@ -149,7 +149,7 @@ jest.mock('backend.ai-ui', () => {
         },
       },
     }),
-    useFetchKey: () => [isoDate, jest.fn(), isoDate],
+    useFetchKey: () => [isoDate, vi.fn(), isoDate],
     convertToNumber: (value: any) => parseFloat(value) || 0,
     processMemoryValue: (value: any) => {
       if (!value || value === 'Infinity' || value === Infinity) return value;
@@ -190,12 +190,14 @@ jest.mock('backend.ai-ui', () => {
   };
 });
 
-jest.mock('./SharedResourceGroupSelectForCurrentProject', () => {
+vi.mock('./SharedResourceGroupSelectForCurrentProject', () => {
   const MockedComponent = () => (
     <div data-testid="resource-group-select">Select</div>
   );
   MockedComponent.displayName = 'SharedResourceGroupSelectForCurrentProject';
-  return MockedComponent;
+  // Source uses `import X from ...`, so the factory must return a module
+  // namespace with a `default` export, not the component directly.
+  return { default: MockedComponent };
 });
 
 // Helper function to create mock return value
@@ -212,7 +214,7 @@ const createMockReturnValue = (checkPresetInfo: any) =>
       checkPresetInfo,
     },
     {
-      refetch: jest.fn(),
+      refetch: vi.fn(),
     },
   ] as const;
 
@@ -237,7 +239,7 @@ TestWrapper.displayName = 'TestWrapper';
 describe('MyResourceWithinResourceGroup', () => {
   let queryClient: QueryClient;
 
-  const mockHook = jest.spyOn(
+  const mockHook = vi.spyOn(
     useResourceLimitAndRemainingModule,
     'useResourceLimitAndRemaining',
   );
@@ -249,7 +251,7 @@ describe('MyResourceWithinResourceGroup', () => {
   });
 
   afterEach(() => {
-    jest.clearAllMocks();
+    vi.clearAllMocks();
     mockHook.mockReset();
   });
 

react/src/components/MyResourceWithinResourceGroup.test.tsx

@@ -13,7 +13,6 @@ import {
   checkSslMismatch,
   checkUrlFields,
 } from '../configRules';
-import { describe, expect, it } from '@jest/globals';
 
 const validMenuKeys = [
   'start',

react/src/diagnostics/rules/__tests__/configRules.test.ts

@@ -11,7 +11,6 @@ import {
   parseCspConnectSrc,
   parseCspDirective,
 } from '../cspRules';
-import { describe, expect, it } from '@jest/globals';
 
 describe('parseCspConnectSrc', () => {
   it('should return empty array for null/undefined input', () => {

react/src/diagnostics/rules/__tests__/cspRules.test.ts

@@ -3,7 +3,6 @@
  Copyright (c) 2015-2026 Lablup Inc. All rights reserved.
  */
 import { checkEndpointReachability } from '../endpointRules';
-import { describe, expect, it } from '@jest/globals';
 
 describe('checkEndpointReachability', () => {
   it('should return null when endpoint is empty', () => {

react/src/diagnostics/rules/__tests__/endpointRules.test.ts

@@ -4,7 +4,6 @@
  */
 import { checkStorageVolumeHealth } from '../storageProxyRules';
 import type { StorageVolumeInfo } from '../storageProxyRules';
-import { describe, expect, it } from '@jest/globals';
 
 describe('checkStorageVolumeHealth', () => {
   it('should return null when usage data is missing', () => {

react/src/diagnostics/rules/__tests__/storageProxyRules.test.ts

@@ -228,7 +228,7 @@ describe('BackendAIMetadataStore', () => {
 
   it('has a readImageMetadata method that returns a Promise', () => {
     const originalFetch = global.fetch;
-    global.fetch = jest.fn().mockRejectedValue(new Error('offline'));
+    global.fetch = vi.fn().mockRejectedValue(new Error('offline'));
 
     const result = backendaiMetadata.readImageMetadata();
     expect(result).toBeInstanceOf(Promise);
@@ -245,7 +245,7 @@ describe('BackendAIMetadataStore', () => {
       tagReplace: {},
     };
 
-    global.fetch = jest.fn().mockResolvedValue({
+    global.fetch = vi.fn().mockResolvedValue({
       json: () => Promise.resolve(mockPayload),
     } as unknown as Response);
 
@@ -265,7 +265,7 @@ describe('BackendAIMetadataStore', () => {
   });
 
   it('silently handles fetch failure without throwing', async () => {
-    global.fetch = jest.fn().mockRejectedValue(new Error('network error'));
+    global.fetch = vi.fn().mockRejectedValue(new Error('network error'));
 
     await expect(
       backendaiMetadata.readImageMetadata(),
@@ -279,11 +279,11 @@ describe('BackendAIMetadataStore', () => {
 
 describe('BackendAITasker', () => {
   beforeEach(() => {
-    jest.useFakeTimers();
+    vi.useFakeTimers();
   });
 
   afterEach(() => {
-    jest.useRealTimers();
+    vi.useRealTimers();
   });
 
   describe('add()', () => {