Collapsed Nodes corrupts DoOnce Nodes / Intermittent issue

UE4 4.7.6
Win 7

Please note this is an intermittent issue and reproducing it took me a few tries on a clean blank project.
I first discovered this working on an existing project and i had a large section collapsed.
This resulted in having to recreate and rewire a lot of DoOnce nodes.

Not a train smash but worth a mention.
Keep in mind reproducing this is not an exact art. Sometimes i can do it more than 20 times. Sometimes just once.
Here is the error we are going to reproduce.

http://puu.sh/htUk6/bfd86257fe.png

Ok now on to reproducing this issue.
Create a new Character Blueprint.

From Event begin play wire print string.
Collapse it.

http://puu.sh/htUBe/3f4e5358e3.png

Add a DoOnce and plug in the input.
Create another input and plug it into the reset.
Also add an output pin and plug in the print string to it.

http://puu.sh/htUEZ/cdb1b1f154.png

Click compile.
All is good.

Now rename the input nodes. I named mine 3 and 2.
I renamed the second one to two and clicked compile. All was ok.
After renaming the first input to 3 and selecting compile, i received the error.

http://puu.sh/htUMH/842a469bb1.png

Please note again. This is intermittent. It does not always occur. But it does occur.
The log message displays this, in this specific instance

*> LogSavePackage: Moving

‘…/…/…/…/…/…/Unreal
Projects/BugReport/Saved/CharacterBPA7EAA92F492947F4DA20EB9D894E5246.tmp’
to ‘…/…/…/…/…/…/Unreal
Projects/BugReport/Content/CharacterBP.uasset’
BlueprintLog: New page: Compile
CharacterBP LogBlueprint:Warning:
[compiler] Warning Warning: Pin
‘execute’ on boundary node
‘K2Node_MacroInstance_216’ could not
be found in the composite node
‘EdGraphSchema_K2_153’
LogBlueprint:Error: [compiler] Error
Failed to collapse tunnel DoOnce
LogBlueprint:Error: [compiler] Error
Unexpected node type
K2Node_MacroInstance encountered at
DoOnce LogBlueprint:Error: [compiler]
Error Unexpected node type
K2Node_MacroInstance encountered at
DoOnce LogBlueprint:Warning:
[compiler] Warning [0862.41] Compile
of CharacterBP failed. 3 Fatal
Issue(s) 1 Warning(s) [in 93 ms]
BlueprintEditorCompileResults:Warning:
Warning Warning: Pin ‘execute’ on
boundary node
‘K2Node_MacroInstance_216’ could not
be found in the composite node
‘EdGraphSchema_K2_153’
BlueprintEditorCompileResults:Error:
Error Failed to collapse tunnel
DoOnce
BlueprintEditorCompileResults:Error:
Error Unexpected node type
K2Node_MacroInstance encountered at
DoOnce
BlueprintEditorCompileResults:Error:
Error Unexpected node type
K2Node_MacroInstance encountered at
DoOnce
BlueprintEditorCompileResults:Warning:
Warning [0862.41] Compile of
CharacterBP failed. 3 Fatal Issue(s) 1
Warning(s) [in 93 ms]*

Hey ,

I have replicated your example a few times throughout the day today. Unfortunately, I have not been able to reproduce the issue that you’re explaining. I know that you stated that it seems to have a low repro however, I haven’t gotten it to happen once.

Would you please write out exactly how you’re getting this error to happen, or zip a blank project with the issue already occurring within a blueprint so I can try to reproduce on our end? If you choose to send a project that has this issue, you can either provide the link here, or through a PM on the forums.

Either way, I’d greatly appreciate more information to be able to reproduce this issue so I can submit the bug to our developers.

Thank you, looking forward to hearing back from you. :slight_smile:

Hi.

https://www…com/s/ffnz8lk24wjw1tr/BugReport.zip?dl=0

There is the file saved after getting the issue to reproduce. It seems to happen easier if something is already plugged in and compiled and then renaming it.

Hope this helps.
Dont stress about the link being public. Its black project with nothing inside of it except for the bug.

Hey ,

Thank you so much for providing me that project. I was able to get it to have an error the second time attempting it. This issue has been reported. If for any reason you need to reference this report, please feel free to refer to: UE-11874

Cheers!

greetings from the future! Still running into this issue