refactor(core): preserve original error as cause on DuplicateExecutionError

packages/cli/src/errors/duplicate-execution.error.ts

@@ -1,7 +1,12 @@
 import { OperationalError } from 'n8n-workflow';
 
 export class DuplicateExecutionError extends OperationalError {
-	constructor(readonly deduplicationKey: string) {
-		super(`Execution with deduplication key "${deduplicationKey}" already exists`);
+	constructor(
+		readonly deduplicationKey: string,
+		cause?: Error,
+	) {
+		super(`Execution with deduplication key "${deduplicationKey}" already exists`, {
+			cause,
+		});
 	}
 }

packages/cli/src/executions/__tests__/execution-persistence.test.ts

@@ -185,6 +185,7 @@ describe('ExecutionPersistence', () => {
 				);
 				await expect(executionPersistence.create(payloadWithKey)).rejects.toMatchObject({
 					deduplicationKey: 'wf-1:node-1:1700000000000',
+					cause: uniqueViolation,
 				});
 			});
 

packages/cli/src/executions/execution-persistence.ts

@@ -68,7 +68,7 @@ export class ExecutionPersistence {
 			});
 		} catch (error) {
 			if (executionEntity.deduplicationKey && isUniqueViolationError(error)) {
-				throw new DuplicateExecutionError(executionEntity.deduplicationKey);
+				throw new DuplicateExecutionError(executionEntity.deduplicationKey, error as Error);
 			}
 			throw error;
 		}

packages/cli/src/executions/is-unique-violation-error.ts

@@ -8,6 +8,6 @@ const UNIQUE_VIOLATION_CODES = new Set([
 
 export function isUniqueViolationError(error: unknown): boolean {
 	if (!(error instanceof QueryFailedError)) return false;
-	const driverError = (error as unknown as { driverError?: { code?: string } }).driverError;
-	return typeof driverError?.code === 'string' && UNIQUE_VIOLATION_CODES.has(driverError.code);
+	const code = (error.driverError as { code?: unknown })?.code;
+	return typeof code === 'string' && UNIQUE_VIOLATION_CODES.has(code);
 }