bug: Dataflow throws error

[wasnertobias]

Describe the bug

"There was an error displaying the flow. Please report the error.Cannot read properties of undefined (reading 'targetPosition')"

To reproduce

https://app.windmill.dev/flows/get/f/examples/crm_enrichment

1. Click on Flow "Input"
2. Enable dataflow

Expected behavior

Screenshots

No response

Browser information

Chrome 126.0.6478.127

Application version

EE v1.357.0

Additional Context

Might be related to #4012

[rubenfiszel]

I can't reproduce on latest, can you consistently?

[wasnertobias]

"There was an error displaying the flow. Please report the error.undefined"
on EE v1.361.1

Not fixed, but no longer exists with the link and steps described above. Will try to isolate and send you a minimal reproductional example.

[fatonramadani]

"There was an error displaying the flow. Please report the error.undefined" on EE v1.361.1

Not fixed, but no longer exists with the link and steps described above. Will try to isolate and send you a minimal reproductional example.

An issue was that we were using the wrong Id to target the "failure" module when at least one of its input was connected to the flow_input in the dataflow mode.

In the flows that are still not working, do you have a failure module ? if yes, what are its inputs ?

[wasnertobias]

I tried to reproduce on EE v1.362.0 consistently (have it failing consistently, with an example which I don't know how to share):
Have a flow which calls a sub-flow but fails in a step beforehand.
Run the flow, enable the dataflow feature. Now click on the sub-flow. => Error

Still not able to come up with a minimum example... But I got this exception, which might help?

util.DVQacUoi.js:23 there should be two anchors per edge, have: 4

[wasnertobias]

To reproduce 1:1

1. Go to: https://app.windmill.dev/flows/get/u/tobseb/exceptional_flow
2. Now click on step b
3. In the inner flow click on step p
4. Now enable dataflow in the inner flow
   => "There was an error displaying the flow. Please report the error.undefined"

[wasnertobias]

Another 1:1 example:

1. Go to: https://app.windmill.dev/flows/get/f/examples/crm_enrichment
2. Click on flow input
3. Enable dataflow
4. Click on step ae