[JENKINS-50869] Calling `empty` on Groovy list leads to a list being returned, not correct check

Steps to reproduce:

1. Create a freestyle job


2. Add "Execute system Groovy script" build step


3. Add content (see below)


4. Run build with "Use Groovy Sandbox" enabled.


5. Run without "Use Groovy Sandbox" enabled

 

def someArrayList = []


println someArrayList.empty

This works when the sandbox is disabled, but when sandbox is enabled it returns

[]

Instead of

true

like it should.

After downgrading back from Script Security 1.44 to 1.43 the problem is fixed.

I suspect https://issues.jenkins-ci.org/browse/JENKINS-50470 is the problem

---
Originally reported by kylec_32, imported from: Calling `empty` on Groovy list leads to a list being returned, not correct check

• status: Open
  
• priority: Minor
  
• component(s): script-security-plugin
  
• resolution: Unresolved
  
• votes: 1
  
• watchers: 3
  
• imported: 2025-12-09
  

Raw content of original issue

Steps to reproduce:



	
Create a freestyle job

	
Add "Execute system Groovy script" build step

	
Add content (see below)

	
Run build with "Use Groovy Sandbox" enabled.

	
Run without "Use Groovy Sandbox" enabled



 



def someArrayList = []


println someArrayList.empty





This works when the sandbox is disabled, but when sandbox is enabled it returns



[]





Instead of



true





like it should.


After downgrading back from Script Security 1.44 to 1.43 the problem is fixed. 

 I suspect https://issues.jenkins-ci.org/browse/JENKINS-50470 is the problem

environment

```
Jenkins 2.117

Script Security 1.44
```