[BUG] Merge node doesn't wait for both inputs

[Nathan_Freire]

Describe the problem/error/question

Hi there! Firstly, thanks for n8n! It’s awesome!

I believe I’ve found a bug in the Merge node. In the workflow bellow I’d expect that the “NO OP 2” node would never get executed since:

1. There was no data going into the Input 2 of the Merge node
2. The mode of the Merge node is set to Choose Branch
3. The Output Type is set to Wait for both inputs to arrive.

Here is an execution of the workflow:

Here is the problematic workflow:

Interestingly enough, if you change the Output option of the Merge node to Input 2 and then swap the incoming connections between the inputs, it works as expected, that is, the “NO OP 2” node never gets executed:

Could you guys clarify if this behavior is expected or if there is indeed a bug?

Thanks!

Information on your n8n setup

• n8n version: 0.230.3
• Database: Postgres
• n8n EXECUTIONS_PROCESS setting (default: own, main): main
• Running n8n via (Docker, npm, n8n cloud, desktop app): Docker self-hosted with Queue Mode (3 workers, 1 main instance, no webhook instances)
• Operating system: Alpine (official n8n image)

[Jon]

Hey @Nathan_Freire,

Welcome to the community

This is something we have been aware of a while and I believe it will be fixed in v1.0 which will be release soon.