types: Add (passing) regression test for #5396

test/integration/bun-types/fixture/5396.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it, jest, mock, spyOn } from "bun:test";
+
+class AnyDTO {
+  anyField: string = "any_value";
+}
+
+class AnyClass {
+  async anyMethod(): Promise<AnyDTO> {
+    return new AnyDTO();
+  }
+}
+
+const anyObject: AnyClass = {
+  anyMethod: jest.fn(),
+};
+
+describe("Any describe", () => {
+  it("should return any value", async () => {
+    spyOn(anyObject, "anyMethod").mockResolvedValue({ anyField: "any_value" });
+    const anyValue = await anyObject.anyMethod();
+
+    expect(anyValue).toEqual({ anyField: "any_value" });
+  });
+});
+
+const mockSomething = mock((): string => "hi");
+mockSomething.mockImplementation(() => "hello");
+mockSomething.mockReturnValue("hello");