NOTIFICATION_PREDELETE's timing across nodes when deleting a scene tree branch is off

[ershn]

Tested versions

• Reproducible in 4.2.1.stable
• Not reproducible in 4.1.3.stable

System information

Godot v4.2.1.stable.mono - Windows 10.0.19045 - Vulkan (Forward+) - dedicated Radeon RX 580 Series (Advanced Micro Devices, Inc.; 31.0.21905.1001) - AMD Ryzen 7 2700X Eight-Core Processor (16 Threads)

Issue description

Problem

When the root node of a branch is freed, NOTIFICATION_PREDELETE isn't sent in a consistent order to the nodes of the branch.

In a scene that has the following hierarchy:

A--
| AA-
  | AAA
  | AAB
| AB-
  | ABA
  | ABB

If you free A-- in 4.2.1, notifications will be sent in the following order:

A-- NOTIFICATION_PREDELETE
ABB _exit_tree() callback
ABB tree_exiting signal
ABB NOTIFICATION_EXIT_TREE
ABA _exit_tree() callback
ABA tree_exiting signal
ABA NOTIFICATION_EXIT_TREE
AB- _exit_tree() callback
AB- tree_exiting signal
AB- NOTIFICATION_EXIT_TREE
AAB _exit_tree() callback
AAB tree_exiting signal
AAB NOTIFICATION_EXIT_TREE
AAA _exit_tree() callback
AAA tree_exiting signal
AAA NOTIFICATION_EXIT_TREE
AA- _exit_tree() callback
AA- tree_exiting signal
AA- NOTIFICATION_EXIT_TREE
A-- _exit_tree() callback
A-- tree_exiting signal
A-- NOTIFICATION_EXIT_TREE
ABB tree_exited signal
ABA tree_exited signal
AB- tree_exited signal
AAB tree_exited signal
AAA tree_exited signal
AA- tree_exited signal
A-- tree_exited signal
AB- NOTIFICATION_PREDELETE
ABB NOTIFICATION_PREDELETE
ABA NOTIFICATION_PREDELETE
AA- NOTIFICATION_PREDELETE
AAB NOTIFICATION_PREDELETE
AAA NOTIFICATION_PREDELETE

• NOTIFICATION_PREDELETE is sent to A-- before NOTIFICATION_EXIT_TREE
• NOTIFICATION_PREDELETE isn't sent to the children in the same order as the other notifications

Doing the same thing in 4.1.3 results in the following output:

ABB _exit_tree() callback
ABB tree_exiting signal
ABB NOTIFICATION_EXIT_TREE
ABA _exit_tree() callback
ABA tree_exiting signal
ABA NOTIFICATION_EXIT_TREE
AB- _exit_tree() callback
AB- tree_exiting signal
AB- NOTIFICATION_EXIT_TREE
AAB _exit_tree() callback
AAB tree_exiting signal
AAB NOTIFICATION_EXIT_TREE
AAA _exit_tree() callback
AAA tree_exiting signal
AAA NOTIFICATION_EXIT_TREE
AA- _exit_tree() callback
AA- tree_exiting signal
AA- NOTIFICATION_EXIT_TREE
A-- _exit_tree() callback
A-- tree_exiting signal
A-- NOTIFICATION_EXIT_TREE
ABB tree_exited signal
ABA tree_exited signal
AB- tree_exited signal
AAB tree_exited signal
AAA tree_exited signal
AA- tree_exited signal
A-- tree_exited signal
ABB NOTIFICATION_PREDELETE
ABA NOTIFICATION_PREDELETE
AB- NOTIFICATION_PREDELETE
AAB NOTIFICATION_PREDELETE
AAA NOTIFICATION_PREDELETE
AA- NOTIFICATION_PREDELETE
A-- NOTIFICATION_PREDELETE

In this case there is no problem.

Expected behavior

I expect the timing of NOTIFICATION_PREDELETE to be the same as in 4.1.3.

Notes

• This issue was first reported in Document the exact order of all lifetime signals/callbacks/notifications godot-docs#5492 (comment)
• I'm using the scene provided by KoBeWi from the issue above

Steps to reproduce

1. open the MRP and run the current scene
2. the notifications' order will be printed to the output

Minimal reproduction project (MRP)

MRP.zip