When using an environment variable to define the prefix for a custom tool home, such as ${LOCALAPPDATA}, the default home location is still appended to the tool home when it shouldn't be.

For example, I have a custom tool called 'mytool' with a trivial batch script installer:

@echo off
echo Installed mytool

and a custom tool home location of ${PROGRAMDATA}

I created a simple pipeline which is:

node('win') {
bat " echo ${tool 'mytool'} "
}

The expected relevant output should be C:\ProgramData, but is C:\Jenkins\tools\com.cloudbees.jenkins.plugins.customtools.CustomTool\mytool\C:\ProgramData

If I manually resolve C:\ProgramData as the tool home (that is, I made the tool home location literally "C:\ProgramData"), then the tool home is configured correctly and outputs only "C:\ProgramData". For some installers, this is acceptable, however I need to use the LocalAppData directory, which contains the username of the build agent. I haven't been able to find a workaround that tricks the tool home into thinking it's rooted path.

I was able to reproduce this issue using the same methodology on both the host build agent, Ubuntu, and on a remote build agent, Windows. Let me know if there's anything I can do to help out.