The Gantt will be crashed after add new predecessor for a task

[benjaminservicemax]

Dear Bryntum Team,

We found the Gantt will get crashed after add the "Summary #2" predecessor for "Task 1". It also can reproduce on the basic example with the following test data:

gntt-basic-crash-reproduce.gif (1.2 MiB) Viewed 542 times

Reproduced on Gantt-pro-6.1.15.
Here is my test data:

tasks.json

(15.92 KiB) Downloaded 38 times

dependencies.json

(1.34 KiB) Downloaded 39 times

[arcady]

The dependency is invalid since it builds a cycle. This should be prevented by the UI but something goes wrong there. I've made a ticket to investigate & fix this: https://app.assembla.com/spaces/bryntum/tickets/9678-cyclic-dependency/details
Thank you for the feedback!