Module env 

The process environment, read once.

Everything the game needs to know about the process it runs in is gathered here, in main, and passed down: the home directory, the user name, the working directory, where the state lives, whether the binary runs inside the game shell, and a few knobs that tests and developers use. No game logic reads std::env or the process working directory after this, so every rule below this layer is a plain function of its inputs and tests never chdir or set_var.

variable	field	meaning
HOME	Env::home	the logical home directory
USER	Env::user	the player’s name (player when unset)
SHELLGAME_STATE_DIR, XDG_CONFIG_HOME	Env::state_dir	where state.json lives
SHELLGAME_WORKSPACE	Env::workspace_override	workspace of a new game
SHELLGAME_WRAPPER	Env::wrapped	the binary runs inside the game shell
TMPDIR	Env::tmpdir	a second place remove may delete from
SHELL	Env::shell	the player’s login shell, for shell detection
SHELLGAME_FORCE_SHELL	Env::force_shell	bash or fish: which game shell to start
SHELLGAME_UPDATE_URL	Env::update_url	where shellgame update downloads from

An empty value counts as unset for every variable, as it does in the Python version, where "" is falsy. NO_COLOR and friends are not read here: anstream handles them when output is written.

Structs

Env

What the game knows about the process it runs in. Built once by Env::from_process and passed down by reference; tests build one with Env::new or a struct literal.