Nushell: detect Python and Node environments

config.nu

# just a partial config, only look at env_change
{
  hooks: {
    env_change: {
      PWD: [
        {
          # if you enter a python project
          condition: {|before, after| ["pyproject.toml" "requirements.txt"] | any {|f| $f | path exists } }
          # drop any prior virtualenv, then use a new one if it exists
          code: "
            if ('.venv/bin/python' | path exists) {
              let-env PATH = ($env.PATH | split row (char esep) | filter {|p| not $p =~ '.venv' } | prepend $\"($env.PWD)/.venv/bin\")
            } else {
              let-env PATH = ($env.PATH | split row (char esep) | filter {|p| not $p =~ '.venv' })
            }
          "
        },
        {
          # if you enter a node project with nvm
          condition: {|before, after| ".nvmrc" | path exists }
          # drop any prior nvm context, and use a node version from fnm if one exists
          code: "(
            if ($\"($env.HOME)/.fnm/node-versions/v(cat .nvmrc)/installation/bin\" | path exists) {
                let-env PATH = ($env.PATH | split row (char esep) | filter {|p| not p =~ '.fnm'} | prepend $\"($env.HOME)/.fnm/node-versions/v(cat .nvmrc)/installation/bin\")
            } else {
              print $\"Node v(cat .nvmrc) is not installed\";
              print $\"Please run: fnm install (cat .nvmrc)\"
                let-env PATH = ($env.PATH | split row (char esep) | filter {|p| not p =~ '.fnm'})
            }
          )"
        }
      ]
    }
  }
}