Define prompt execution contract

internal/promptexec/copy.go

@@ -0,0 +1,80 @@
+package promptexec
+
+import (
+	"strings"
+	"unicode/utf8"
+)
+
+func copyPreparation(value Preparation) Preparation {
+	value.InputHashes = copyStringMap(value.InputHashes)
+	return value
+}
+
+func copyPreparationDebug(value *PreparationDebug) *PreparationDebug {
+	if value == nil {
+		return nil
+	}
+	copy := *value
+	copy.RenderedMessages = append([]RenderedMessage(nil), value.RenderedMessages...)
+	copy.StructuredSchema = append([]byte(nil), value.StructuredSchema...)
+	copy.ParametersJSON = append([]byte(nil), value.ParametersJSON...)
+	return &copy
+}
+
+func copyExecution(value Execution) Execution {
+	value.InputHashes = copyStringMap(value.InputHashes)
+	value.Validation.Diagnostics = boundDiagnostics(value.Validation.Diagnostics)
+	value.RawOutput = append([]byte(nil), value.RawOutput...)
+	value.Debug = copyExecutionDebug(value.Debug)
+	return value
+}
+
+func copyExecutionDebug(value *ExecutionDebug) *ExecutionDebug {
+	if value == nil {
+		return nil
+	}
+	copy := *value
+	copy.RawOutput = append([]byte(nil), value.RawOutput...)
+	copy.ValidationDiagnostics = boundDiagnostics(value.ValidationDiagnostics)
+	return &copy
+}
+
+func copyStringMap(value map[string]string) map[string]string {
+	if value == nil {
+		return nil
+	}
+	copy := make(map[string]string, len(value))
+	for key, item := range value {
+		copy[key] = item
+	}
+	return copy
+}
+
+func boundDiagnostics(values []string) []string {
+	if len(values) == 0 {
+		return nil
+	}
+	if len(values) > maxValidationDiagnostics {
+		values = values[:maxValidationDiagnostics]
+	}
+	bounded := make([]string, len(values))
+	for index, value := range values {
+		bounded[index] = boundText(value, maxDiagnosticBytes)
+	}
+	return bounded
+}
+
+func boundText(value string, limit int) string {
+	if limit <= 0 || value == "" {
+		return ""
+	}
+	value = strings.ToValidUTF8(value, "<22>")
+	if len(value) <= limit {
+		return value
+	}
+	value = value[:limit]
+	for len(value) > 0 && !utf8.ValidString(value) {
+		value = value[:len(value)-1]
+	}
+	return value
+}