PNPM_HOME does not expand on Windows

[maxichrome]

pnpm version:

7.17.0

Code to reproduce the issue:

n/a

Expected behavior:

%PNPM_HOME% expands when inserted into other environment variables such as Path.

Example

If Path is set to %PNPM_HOME%;%USERPROFILE%\.bin, when opening a shell it becomes C:\Users\user\AppData\Local\pnpm;C:\Users\user\.bin

Actual behavior:

Example

If Path is set to %PNPM_HOME%;%USERPROFILE%\.bin, when opening a shell it becomes %PNPM_HOME%;C:\Users\user\.bin

Additional information:

• node -v prints: v19.1.0
• Windows, macOS, or Linux?: Windows

Suspected cause

This has been reproduced by myself and @maplefins in further testing:

During pnpm setup, pnpm sets an environment variable called PNPM_HOME. On Windows, it does this by directly calling reg.exe instead of using a native system API (see path-extender-windows.ts; also see Workaround below).

Reproduced on

• Windows Server 2022 [20348.1311]
• Windows 11 [22621.898]

Workaround

Update the PNPM_HOME variable via a native API (in a shell or the Environment Variables editor UI).

In PowerShell:

$pnpmHome = [System.Environment]::GetEnvironmentVariable("PNPM_HOME", [System.EnvironmentVariableTarget]::User)
[System.Environment]::SetEnvironmentVariable("PNPM_HOME", $pnpmHome, [System.EnvironmentVariableTarget]::User)

[zkochan]

How can we run then native API? Should we generate a powershell file and run it? As far as I remember Windows doesn't allow to run unsigned ps1 files.

[maxichrome]

I'm unsure what this looks like practically in terms of security-related permissions but you should be able to run the PowerShell executable with the necessary function as an argument

[maxichrome]

Based on the fact this works:

powershell -command "[System.Environment]::SetEnvironmentVariable('PNPM_HOME', '$pnpmHome', [System.EnvironmentVariableTarget]::User)"

path-extender-windows.ts could be modified in a way similar to this:

I know this looks silly, but it's probably the best solution here unless you want to embed a native binary or FFI that somehow calls the API

await execa('powershell', ['-command', '"[System.Environment]::SetEnvironmentVariable(\'${envVarName}\', \'${envVarValue}\', [System.EnvironmentVariableTarget]::User)"'], EXEC_OPTS)

You may want to split this up somehow to avoid the long single string, but that's all for however you want to style your own code :P

[zkochan]

By the way, for this issue there was this suggestion: #4658 (comment)

that I released in v7.17.1

That didn't help?

[zkochan]

Looks like it is solved but only if PNPM_HOME wasn't configured by pnpm older than v7.17

#4658 (comment)

[maxichrome]

yes the findings in that comment make sense with my previous findings! maybe a separate change needs to be made to retrieve, unset, and reset PNPM_HOME to the same value using the current method

(or would unsetting be necessary at all?)