Can we reduce the amount of empty newlines on action output?

[ssbarnea]

The current console output of the action contains a huge amount of empty lines, which only makes it harder to read/debug.

  C:\Windows\system32\wsl.exe --set-default-version 2
  For information on key differences with WSL 2 please visit https://aka.ms/wsl2
  
  
  The operation completed successfully.
  
  
  ]C:\Windows\system32\wsl.exe --update
  Downloading: Windows Subsystem for Linux
  
  
  Installing: Windows Subsystem for Linux
  
  
  Windows Subsystem for Linux has been installed.
  
  

Can we make some changes to avoid these?

When I run the same commands from within the powershell console on the same machine, I do not get any unexpected newlines, so these must be originating from another place.

[Vampire]

Well, it should not be coming from anything I do.

I could at most capture all output and process it, then forward it, but I'd like to avoid that, as it would for example then also not output stuff while a command is running but first capture all output, then post-process it, then output it completely which for veeeery long stuff could also kill the memory and either way is bad as no progress is shown.

What I do is calling exec from @actions/exec, for example in your case first with commandLine set to wsl and args set to --set-default-version and 2, and second with commandLine set to wsl and args set to --update.

Whatever happens then is coming from inside @actions/exec.

[Vampire]

Actually, looking at the actual output like https://github.com/Vampire/setup-wsl/actions/runs/13487602803/job/37680929183 it is not only empty newlines, there are also "spaces between each character" which is not seen in your post above.

This reminded me about what the issue is.
Some versions of the tools output text in UTF-8, some output in UTF-16LE.
For some checks in the action I actually do capture command outputs and check its contents.
In those occasions I indeed capture all output bytes, decode them using UTF-8 and again using UTF-16LE and then check the combined result for what I want to check.

What you see in the link I sent is coming from a tool that outputs UTF-16LE bytes, but the bytes are interpreted as UTF-8 bytes by whatever makes the bytes to text. Probably either something in @actions/exec or in Node.js, I didn't look deeper where it is translated to console output. So probably there would be some encoding detection needed or something like that to properly fix this.