fix(web): localStorage safety, default fetch timeout, visibility-aware polling

web/test/api-client.test.ts

@@ -58,4 +58,79 @@ describe('api client', () => {
       expect(ex.body.code).toBe('invalid_input')
     }
   })
+
+  it('schedules a default 30s timeout and forwards abort to fetch', async () => {
+    // Replace setTimeout with a stub that captures the scheduled callback,
+    // so we can assert the default-timeout scheduling and trigger it manually
+    // without waiting wall-clock 30 seconds.
+    const captured: Array<{ cb: () => void; ms: number }> = []
+    const realSetTimeout = globalThis.setTimeout
+    vi.stubGlobal('setTimeout', ((cb: () => void, ms?: number, ...args: unknown[]) => {
+      if (ms === 30_000) {
+        captured.push({ cb, ms })
+        return 0 as unknown as ReturnType<typeof setTimeout>
+      }
+      return realSetTimeout(cb, ms, ...args)
+    }) as typeof setTimeout)
+
+    try {
+      const fetchMock = vi.spyOn(globalThis, 'fetch').mockImplementation(
+        (_input, init) =>
+          new Promise((_resolve, reject) => {
+            const sig = init?.signal as AbortSignal | undefined
+            sig?.addEventListener('abort', () => {
+              const err = new Error('aborted')
+              err.name = 'AbortError'
+              reject(err)
+            })
+          }),
+      )
+
+      let rejected: unknown = null
+      const promise = request('/api/test').catch((e) => {
+        rejected = e
+      })
+
+      // Allow the request to register its setTimeout + start the fetch.
+      await Promise.resolve()
+
+      expect(captured.length).toBe(1)
+      expect(captured[0].ms).toBe(30_000)
+
+      // Fire the captured timeout callback to simulate elapsed 30s.
+      captured[0].cb()
+      await promise
+
+      expect(rejected).not.toBeNull()
+      const init = fetchMock.mock.calls[0][1] as RequestInit
+      expect((init.signal as AbortSignal).aborted).toBe(true)
+    } finally {
+      vi.unstubAllGlobals()
+    }
+  })
+
+  it('forwards a caller-supplied signal abort to the fetch', async () => {
+    const fetchMock = vi.spyOn(globalThis, 'fetch').mockImplementation(
+      (_input, init) =>
+        new Promise((_resolve, reject) => {
+          const sig = init?.signal as AbortSignal | undefined
+          if (sig) {
+            sig.addEventListener('abort', () => {
+              const err = new Error('aborted')
+              err.name = 'AbortError'
+              reject(err)
+            })
+          }
+        }),
+    )
+
+    const ctl = new AbortController()
+    const promise = request('/api/test', { signal: ctl.signal })
+    const settled = expect(promise).rejects.toThrow()
+    ctl.abort()
+    await settled
+
+    const init = fetchMock.mock.calls[0][1] as RequestInit
+    expect((init.signal as AbortSignal).aborted).toBe(true)
+  })
 })