Struct Environment 

pub struct Environment { /* private fields */ }

A snapshot of the environment a process was started with.

Debug redacts

This holds whatever the process was given, which on a configured host includes LINEAR_API_KEY and GH_PROJECTS_TOKEN. Deriving Debug would put both in any log line, panic message or {:?} that ever touched one, so the implementation below prints the names and never a value.

Implementations

impl Environment

pub fn from_process() -> Self

Capture the environment this process was started with.

Read as OS strings rather than through std::env::vars, which panics on an entry that is not valid Unicode — and a process is handed its environment by whoever spawned it, so that is an input from outside rather than an invariant.

A name that is not Unicode is dropped: no configuration document, no ONETASKGRAPH_ variable and no api_key_env: can spell one, so nothing in this product could ever ask for it. A value that is not Unicode keeps its name in unusable, where the environment layer turns a ONETASKGRAPH_-prefixed one into a refusal naming the variable — because a setting this product cannot read is exactly the thing it may not quietly ignore.

pub fn from_os_pairs( pairs: impl IntoIterator<Item = (OsString, OsString)>, ) -> Self

Build a snapshot from OS strings, sorting out what this product can read.

Separate from from_process so that the sorting is a function of its argument: a hand-built pair is the only way to drive the two not-valid-Unicode cases without one process spawning another.

pub fn from_pairs<K, V>(pairs: impl IntoIterator<Item = (K, V)>) -> Self

where K: Into<String>, V: Into<String>,

Build a snapshot from explicit pairs.

pub fn unusable(&self) -> impl Iterator<Item = &str>

Every name this process was given whose value is not valid Unicode.

pub fn get(&self, name: &str) -> Option<&str>

The value of name, or None when the snapshot does not define it.

pub fn non_empty(&self, name: &str) -> Option<&str>

The value of name when it is set to something other than the empty string.

An exported-but-empty variable is how a shell says “unset this for the child” in practice, and treating XDG_CONFIG_HOME= as a path to the filesystem root would send discovery somewhere nobody asked for.

pub fn iter(&self) -> impl Iterator<Item = (&str, &str)>

Every variable, name and value, in name order.

pub fn names(&self) -> impl Iterator<Item = &str>

Every variable name, in order.

Trait Implementations

impl Clone for Environment

fn clone(&self) -> Environment

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Environment

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Names only. See the type’s own note: a value here may be a live credential.

impl Default for Environment

fn default() -> Environment

Returns the “default value” for a type.

impl Eq for Environment

impl PartialEq for Environment

fn eq(&self, other: &Environment) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Environment