diff --git a/src/hooks/useDrawerUrlState.test.ts b/src/hooks/useDrawerUrlState.test.ts
index 9819bb7..3185534 100644
--- a/src/hooks/useDrawerUrlState.test.ts
+++ b/src/hooks/useDrawerUrlState.test.ts
@@ -58,11 +58,13 @@ function setLocation(url: string): void {
 describe("useDrawerUrlState", () => {
   // `vi.fn()` with no args in vitest 4 is typed `Mock<Procedure |
   // Constructable>`, which carries a constructor signature and won't
-  // assign to `() => void`. Constraining the generic to `vi.fn<() => void>()`
-  // gives a plain function-typed mock that flows directly into `pushState`
-  // / `replaceState` slots.
-  let pushStateMock: ReturnType<typeof vi.fn<() => void>>;
-  let replaceStateMock: ReturnType<typeof vi.fn<() => void>>;
+  // assign to a real `pushState` slot. Constrain the generic to the
+  // `History.pushState` signature so the mock flows into `vi.stubGlobal`
+  // without complaint AND `mock.calls[0]` is typed as a 3-tuple, letting
+  // us read `calls[0][2]` (the URL) without an `as unknown` cast.
+  type PushState = (state: unknown, unused: string, url?: string | URL | null) => void;
+  let pushStateMock: ReturnType<typeof vi.fn<PushState>>;
+  let replaceStateMock: ReturnType<typeof vi.fn<PushState>>;
 
   beforeEach(() => {
     pushStateMock = vi.fn();