[BUG] `--` parameters like `--ts_out` no longer work with npx in npm 11 compared to npm 10 when using pwsh script-shell in Ubuntu and produce `Unexpected token in expression or statement` errors

[ceisele-r]

Is there an existing issue for this?

• I have searched the existing issues

This issue exists in the latest npm version

• I am using the latest npm

Current Behavior

Having a .npmrc that sets script-shell to pwsh:

script-shell=pwsh

...and executing a command like npx protoc --ts_out ./gen that contains a parameter with -- produces the error

ParserError: 
Line |
   1 |  "protoc" --ts_out ./gen
     |             ~~~~~~
     | Unexpected token 'ts_out' in expression or statement.

in npm 11 where the same command is working in npm 10.

Expected Behavior

Executing a command like npx protoc --ts_out ./gen that contains a parameter with -- still works in npm 11 when using pwsh as script-shell (set via .npmrc).

Steps To Reproduce

1. Use Ubuntu with node v24.12.0 and npm 11.6.2 (alternatively: use Github Actions runner with ubuntu-24.04 runner)
2. Create .npmrc file in a directory

script-shell=pwsh

4. Open a bash in this directory
5. Execute npx protoc --ts_out ./gen
6. (Agree to install protoc)
7. See the error

ParserError: 
Line |
   1 |  "protoc" --ts_out ./gen
     |             ~~~~~~
     | Unexpected token 'ts_out' in expression or statement.

Now, switch back to npm 10:
8. npm i -g npm@10
9. Execute npx protoc --ts_out ./gen
10. The command is executed successfully without the Unexpected token error

Environment

• npm: 11.6.2
• Node.js: 24.12.0
• OS Name: Ubuntu
• System Model Name: Github Actions / VM
• npm config:

; "user" config from /home/user/.npmrc

; script-shell = null ; overridden by project

; "project" config from /home/user/Desktop/testc/.npmrc

script-shell = "pwsh"

; node bin location = /home/user/.nvm/versions/node/v24.12.0/bin/node
; node version = v24.12.0
; npm local prefix = /home/user/Desktop/testc
; npm version = 11.6.2
; cwd = /home/user/Desktop/testc
; HOME = /home/user
; Run `npm config ls -l` to show all defaults.