Mise adds a root environment variable

[jdx]

Discussed in #3882

^{Originally posted by orf December 30, 2024}
When using a mise task, there seems to be a mysterious root environment variable that is added:

[tasks.test]
shell = "bash -c" # same with all other shells
run = "env | grep root"

❯ env | rg root | wc -l
       0
❯ mise run test
[test] $ env | rg root
root=/Users/tomforbes/PycharmProjects/project/path/here/

This unfortunately causes a third-party library in a tool we use to explode. Because... of course it would 😭 😭

This isn't documented anywhere, and I can't see anywhere in the code that it is added. It doesn't seem to be my shell config/profile. It also happens with file-based tasks, and with this the environment variable is not set.

Mise versions:

version: 2024.12.22 macos-arm64 (2024-12-30)
activated: yes
shims_on_path: no

build_info:
  Target: aarch64-apple-darwin
  Features: DEFAULT, NATIVE_TLS
  Built: Mon, 30 Dec 2024 00:20:47 +0000
  Rust Version: rustc 1.83.0 (90b35a623 2024-11-26) (Homebrew)
  Profile: release

shell:
  /opt/homebrew/bin/fish
  fish, version 3.7.1

dirs:
  cache: ~/Library/Caches/mise
  config: ~/.config/mise
  data: ~/.local/share/mise
  shims: ~/.local/share/mise/shims
  state: ~/.local/state/mise

env_vars:
  MISE_SHELL=fish

settings:
  cache_prune_age       "7d"    ~/.config/mise/config.toml
  jobs                  1       ~/.config/mise/config.toml
  pipx.uvx              true    ~/.config/mise/config.toml
  status.missing_tools  "never" ~/.config/mise/config.toml
  status.show_tools     false   ~/.config/mise/config.toml
```</div>

[jdx]

I think this was supposed to just be in templates but for some reason it got snuck in as an env var too