Harden public ownership and diagnostic contracts

llm_adapter_internal_test.go

@@ -0,0 +1,96 @@
+package promptkit
+
+import (
+	"context"
+	"reflect"
+	"strconv"
+	"sync"
+	"testing"
+
+	"gitea.maximumdirect.net/eric/promptkit/internal/domain"
+)
+
+func TestPublicLLMClientAdapterGivesClientOwnedNestedValues(t *testing.T) {
+	source := adapterOwnershipRequest()
+	want := adapterOwnershipRequest()
+	client := &retainingMutatingLLMClient{}
+	adapter := publicLLMClientAdapter{client: client}
+
+	if _, err := adapter.Generate(context.Background(), source); err != nil {
+		t.Fatalf("generate: %v", err)
+	}
+	if !reflect.DeepEqual(source, want) {
+		t.Fatalf("client mutation changed prepared source:\ngot  %#v\nwant %#v", source, want)
+	}
+
+	var mutations sync.WaitGroup
+	mutations.Add(1)
+	go func() {
+		defer mutations.Done()
+		for i := 0; i < 10_000; i++ {
+			mutateGenerateRequest(&client.retained, strconv.Itoa(i))
+		}
+	}()
+	for i := 0; i < 10_000; i++ {
+		laterRequest := fromDomainGenerateRequest(source)
+		if laterRequest.Prompt.Messages[0].Content != "source-message" ||
+			laterRequest.Prompt.Messages[0].CacheControl.TTL != "source-ttl" ||
+			laterRequest.Target.ExtraParams["nested"].([]any)[0] != "source-extra" ||
+			laterRequest.StructuredOutput.JSONSchema.Schema.(map[string]any)["enum"].([]any)[0] != "source-schema" {
+			t.Fatal("retained client mutation reached a later execution request")
+		}
+	}
+	mutations.Wait()
+
+	if !reflect.DeepEqual(source, want) {
+		t.Fatalf("retained client mutation changed prepared source:\ngot  %#v\nwant %#v", source, want)
+	}
+}
+
+type retainingMutatingLLMClient struct {
+	retained GenerateRequest
+}
+
+func (c *retainingMutatingLLMClient) Generate(_ context.Context, request GenerateRequest) (*GenerateResponse, error) {
+	c.retained = request
+	mutateGenerateRequest(&c.retained, "client-mutation")
+	return &GenerateResponse{Content: "generated"}, nil
+}
+
+func adapterOwnershipRequest() domain.GenerateRequest {
+	return domain.GenerateRequest{
+		Prompt: domain.RenderedPrompt{
+			SessionID: "source-session",
+			Messages: []domain.RenderedMessage{{
+				Role:    "user",
+				Content: "source-message",
+				CacheControl: &domain.CacheControl{
+					Type: domain.CacheControlEphemeral,
+					TTL:  "source-ttl",
+				},
+			}},
+		},
+		Target: domain.ExecutionTarget{
+			Model:  "source-model",
+			APIKey: "source-api-key",
+			ExtraParams: map[string]any{
+				"nested": []any{"source-extra"},
+			},
+		},
+		StructuredOutput: &domain.StructuredOutputSpec{
+			Type: domain.StructuredOutputJSONSchema,
+			JSONSchema: &domain.StructuredOutputJSONSpec{
+				Name:   "source-schema-name",
+				Strict: true,
+				Schema: map[string]any{"enum": []any{"source-schema"}},
+			},
+		},
+	}
+}
+
+func mutateGenerateRequest(request *GenerateRequest, value string) {
+	request.Prompt.Messages[0].Content = value
+	request.Prompt.Messages[0].CacheControl.TTL = value
+	request.Target.ExtraParams["nested"].([]any)[0] = value
+	request.StructuredOutput.JSONSchema.Schema.(map[string]any)["enum"].([]any)[0] = value
+}