Calling cmd.Parent().PreRunE(cmd, args) in Third lavel of child is making it infinite loop

[tiwarisanjay]

Hi,
In the example .
I am trying to print the PreRunE of add function starting from child.
Command to run :

• go run main.go add addchild addchildchild

Where output supposed to be :

inside init
inside main
inside initConfig
Add Prerun E : addChildChild Function
Add Prerun E  : addChild Function
Add Prerun E : add Function

But Ouptut I am getting is :

inside init
inside main
inside initConfig
Add Prerun E : addChildChild Function
Add Prerun E  : addChild Function
Add Prerun E  : addChild Function
Add Prerun E  : addChild Function
Add Prerun E  : addChild Function
.
.
.

Not sure if I am missing something for the concept. I debug the code and parent for addChild is showing add but something is throwing it in infinite and addChild is calling itself again for parent.

[github-actions]

This issue is being marked as stale due to a long period of inactivity

[johnSchnake]

Interesting bug, thanks for the submission!

I'm looking into it but I ran the debugger and it seems like when it calls its parent PreRunE, the cmd value isn't updated.

This means when it prints its message and calls the parent, it calls the same method again; it doesn't actually traverse up the tree, it just goes up a branch and gets stuck.

Solution tbd; I'm not sure if there is some reason it was implemented that way; eg the 'cmd' is always the cmd that was invoked. It could be useful to always see it through that lens. However, in this particular case it is clearly at odds with what you're trying to do.

[marckhouzam]

I've hit this before somewhere, so let me share my interpretation.

I'm looking into it but I ran the debugger and it seems like when it calls its parent PreRunE, the cmd value isn't updated.
This means when it prints its message and calls the parent, it calls the same method again; it doesn't actually traverse up the tree, it just goes up a branch and gets stuck.

Cobra only calls PreRun/PreRunE for the current command (unlike PersistentPreRun) as can be seen here:

cobra/command.go

Lines 844 to 850 in a599632

	if c.PreRunE != nil {
	if err := c.PreRunE(c, argWoFlags); err != nil {
	return err
	}
	} else if c.PreRun != nil {
	c.PreRun(c, argWoFlags)
	}

Going up the chain of PreRunE in the example of this PR is not done by Cobra, but is done by the code using Cobra. So the issue seems to be here:
https://github.com/tiwarisanjay/godemo/blob/3ed63322a2ab4e4cab8ba0c04b2695612eba0d5e/cmd/addChildChild.go#L50
where the line

return cmd.Parent().PreRunE(cmd, args)

should be

return cmd.Parent().PreRunE(cmd.Parent(), args)

At least that is my impression.