test: cover Ollama request timeout errors

- Verify generation requests include an abort signal
- Assert timeout-related abort errors propagate with the expected error name
- Restore the global fetch implementation after the test

src/ollama.test.ts

@@ -62,3 +62,20 @@ it("propagates an error when Ollama is unreachable", async () => {
     globalThis.fetch = originalFetch;
   }
 });
+
+it("propagates an error when an Ollama request times out", async () => {
+  const originalFetch = globalThis.fetch;
+
+  globalThis.fetch = async (_input, init) => {
+    assert.ok(init?.signal);
+    throw new DOMException("The operation was aborted", "AbortError");
+  };
+
+  try {
+    await assert.rejects(generateResponse("Explain a REST API."), {
+      name: "AbortError",
+    });
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});