From 0f22f3be92db71b6cb37382bc77c86fcd1b9e8de Mon Sep 17 00:00:00 2001
From: Csaba Tuncsik <csaba@n8n.io>
Date: Tue, 2 Sep 2025 15:16:42 +0200
Subject: [PATCH] fix(core): Ensure getNodeOutputs always returns an array
 (#19069)

---
 packages/workflow/src/node-helpers.ts |  7 +++++--
 packages/workflow/src/workflow.ts     | 13 ++++---------
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/packages/workflow/src/node-helpers.ts b/packages/workflow/src/node-helpers.ts
index 4d0d8fcf64..c12329d7f9 100644
--- a/packages/workflow/src/node-helpers.ts
+++ b/packages/workflow/src/node-helpers.ts
@@ -1047,12 +1047,15 @@ export function getNodeOutputs(
 	} else {
 		// Calculate the outputs dynamically
 		try {
-			outputs = (workflow.expression.getSimpleParameterValue(
+			const result = workflow.expression.getSimpleParameterValue(
 				node,
 				nodeTypeData.outputs,
 				'internal',
 				{},
-			) || []) as NodeConnectionType[];
+			);
+			outputs = Array.isArray(result)
+				? (result as Array<NodeConnectionType | INodeOutputConfiguration>)
+				: [];
 		} catch (e) {
 			console.warn('Could not calculate outputs dynamically for node: ', node.name);
 		}
diff --git a/packages/workflow/src/workflow.ts b/packages/workflow/src/workflow.ts
index 49d23070c9..c79cb612cc 100644
--- a/packages/workflow/src/workflow.ts
+++ b/packages/workflow/src/workflow.ts
@@ -697,15 +697,10 @@ export class Workflow {
 			const outputs = NodeHelpers.getNodeOutputs(this, node, nodeType.description);
 			const nonMainConnectionTypes: NodeConnectionType[] = [];
 
-			// Defensive check: NodeHelpers.getNodeOutputs should always return an array,
-			// but in some edge cases (particularly during testing with incomplete node setup),
-			// it may return undefined or null
-			if (Array.isArray(outputs)) {
-				for (const output of outputs) {
-					const type = typeof output === 'string' ? output : output.type;
-					if (type !== NodeConnectionTypes.Main) {
-						nonMainConnectionTypes.push(type);
-					}
+			for (const output of outputs) {
+				const type = typeof output === 'string' ? output : output.type;
+				if (type !== NodeConnectionTypes.Main) {
+					nonMainConnectionTypes.push(type);
 				}
 			}