[Bug]: Hop Gui lets users create loops in workflows

[bamaer]

Apache Hop version?

SNAPSHOT-20240910

Java version?

openjdk version "17.0.11" 2024-04-16 LTS

Operating system

macOS

What happened?

Error.mp4

When Apache Hop users try to create a hop in the opposite direction of an existing hop, there's an Ok/Cancel popup that warns about the loop, but the hop is created anyway.

This is caused by the check for loops here, which causes hopCandidate to disappear and become null in workflowMeta.removeWorkflowHop(hopCandidate);

a quick fix/workaround could be to keep hopCandidate in a second variable to make sure it doesn't get lost.
However, hopCandidate shouldn't get lost, and there could be similar issues in the pipeline hops.

Issue Priority

Priority: 3

Issue Component

Component: Hop Gui

[bamaer]

.take-issue

[bamaer]

the easiest fix to prevent this in the workflow editor is to remove the ok/cancel options in this dialog, and only use an ok button. There shouldn't be any choices for an option that is not allowed: click 'ok' and the incorrect is never created or removed right away.