Function TestCache_EmptyResponseIsNotCached

pkg/runtime/cache_test.go:215–242

TestCache_EmptyResponseIsNotCached documents that the cache_response stop-hook deliberately drops empty (whitespace-only) assistant responses on the floor: replaying nothing on a future turn would leave the user staring at a blank reply with no recourse but to ask again, so the model is called every

(t *testing.T)

// the user staring at a blank reply with no recourse but to ask again,
// so the model is called every time.
func TestCache_EmptyResponseIsNotCached(t *testing.T) {
	t.Parallel()

	c, err := cache.New(cache.Config{Enabled: true})
	require.NoError(t, err)

	// Two empty-response streams; we expect the model to be called both
	// times because the empty answer must never reach the cache.
	stream1 := newStreamBuilder().AddContent("").AddStopWithUsage(5, 0).Build()
	stream2 := newStreamBuilder().AddContent("").AddStopWithUsage(5, 0).Build()
	prov := &messageRecordingProvider{
		id:      "test/mock-model",
		streams: []*mockStream{stream1, stream2},
	}

	sess1 := session.New(session.WithUserMessage("silent treatment"))
	runWithCache(t, c, prov, sess1)
	sess2 := session.New(session.WithUserMessage("silent treatment"))
	runWithCache(t, c, prov, sess2)

	prov.mu.Lock()
	defer prov.mu.Unlock()
	assert.Len(t, prov.recordedMessages, 2,
		"empty responses must not be cached; the model must be called every time")

	_, found := c.Lookup("silent treatment")
	assert.False(t, found, "empty assistant response must not appear in the cache")
}

func hasAgentChoice(events []Event, content string) bool {
	for _, ev := range events {