promptkit/nested_error_contract_test.go

package promptkit_test

import (
	"context"
	"errors"
	"strings"
	"testing"

	"go.maximumdirect.net/promptkit"
)

func TestNestedErrorsRetainEachCauseWithoutDuplicatingDiagnostics(t *testing.T) {
	cause := errors.New("independent-leaf-diagnostic")
	for range 10 {
		parent := newSimpleEngine(t, "parent", promptkit.WithLLMClient(&fakeLLMClient{err: cause}))
		_, err := parent.Run(context.Background(), promptkit.RunRequest{PromptID: "prompt"})
		if !errors.Is(err, cause) || !errors.Is(err, promptkit.ErrLLMGenerate) {
			t.Fatalf("lost owner or cause: %v", err)
		}
		if strings.Count(err.Error(), "independent-leaf-diagnostic") != 1 {
			t.Fatalf("duplicated leaf: %v", err)
		}
		cause = err
	}
}

type nestedErrorReader struct{ cause error }

func (r nestedErrorReader) Read(context.Context, promptkit.ArtifactRef) (*promptkit.Artifact, error) {
	return nil, r.cause
}

func TestNestedEngineErrorKeepsOwningOperation(t *testing.T) {
	child := newSimpleEngine(t, "child")
	_, childErr := child.Run(context.Background(), promptkit.RunRequest{PromptID: "missing"})
	if !errors.Is(childErr, promptkit.ErrPromptNotFound) {
		t.Fatalf("child error = %v", childErr)
	}
	client := &fakeLLMClient{err: childErr}
	parent := newSimpleEngine(t, "hello", promptkit.WithLLMClient(client))
	_, err := parent.Run(context.Background(), promptkit.RunRequest{PromptID: "prompt"})
	if !errors.Is(err, promptkit.ErrLLMGenerate) || !errors.Is(err, childErr) || !errors.Is(err, promptkit.ErrPromptNotFound) {
		t.Fatalf("generation error = %v", err)
	}

	readerParent := newSimpleEngine(t, "hello", promptkit.WithArtifactReader(nestedErrorReader{cause: childErr}))
	_, err = readerParent.Prepare(context.Background(), promptkit.RunRequest{PromptID: "prompt", Inputs: map[string]promptkit.ArtifactRef{"extra": promptkit.Inline("data")}})
	if !errors.Is(err, promptkit.ErrArtifactLoad) || !errors.Is(err, childErr) || !errors.Is(err, promptkit.ErrPromptNotFound) {
		t.Fatalf("artifact error = %v", err)
	}
}

func TestObservedNestedErrorsKeepTheParentOperation(t *testing.T) {
	child := newSimpleEngine(t, "child")
	_, childErr := child.Run(context.Background(), promptkit.RunRequest{PromptID: "missing"})
	for _, mode := range []string{"run", "prepared", "repair", "artifact"} {
		t.Run(mode, func(t *testing.T) {
			var events []promptkit.ExecutionEvent
			req := promptkit.RunRequest{PromptID: "prompt", Observer: func(e promptkit.ExecutionEvent) { events = append(events, e) }}
			engine := newSimpleEngine(t, "parent", promptkit.WithLLMClient(&fakeLLMClient{err: childErr}))
			want, owner := promptkit.ExecutionFailureGeneration, promptkit.ErrLLMGenerate
			if mode == "artifact" {
				engine = newSimpleEngine(t, "parent", promptkit.WithArtifactReader(nestedErrorReader{cause: childErr}))
				req.Inputs = map[string]promptkit.ArtifactRef{"extra": promptkit.Inline("data")}
				want, owner = promptkit.ExecutionFailureArtifactLoad, promptkit.ErrArtifactLoad
			}
			if mode == "repair" {
				calls := 0
				engine = newSimpleEngine(t, "parent", promptkit.WithLLMClient(observationClientFunc(func(context.Context, promptkit.GenerateRequest) (*promptkit.GenerateResponse, error) {
					calls++
					if calls == 1 {
						return &promptkit.GenerateResponse{Content: "invalid JSON"}, nil
					}
					return nil, childErr
				})))
				req.Validation = &promptkit.OutputContract{Format: promptkit.FormatJSON, ValidationMode: promptkit.ValidationJSON, RepairAttempts: 1}
			}
			var err error
			if mode == "prepared" {
				handle, prepErr := engine.PrepareExecution(context.Background(), req)
				if prepErr != nil {
					t.Fatal(prepErr)
				}
				_, err = engine.RunPrepared(context.Background(), handle)
			} else {
				_, err = engine.Run(context.Background(), req)
			}
			if !errors.Is(err, owner) || !errors.Is(err, childErr) {
				t.Fatalf("lost owner/cause: %v", err)
			}
			if len(events) == 0 || events[len(events)-1].Failure != want {
				t.Fatalf("terminal classification: %+v", events)
			}
			if mode != "artifact" && events[len(events)-2].Failure != want {
				t.Fatalf("attempt classification: %+v", events)
			}
		})
	}
}