Struct LocalCluster 

pub struct LocalCluster { /* private fields */ }

A self-spawning local cluster: re-runs the current executable once per rank as a separate OS process, each pointed at a generated loopback hostfile, capturing one rank’s stdout.

This exercises the real DistConfig::load / connect path over real TCP sockets in separate address spaces — the genuine deployment shape minus the physical wire.

Implementations

impl LocalCluster

pub fn new(world: u32) -> Self

A world-rank cluster over loopback TCP, capturing rank 0’s stdout.

pub fn backend(self, backend: TransportBackend) -> Self

Override the transport backend written into the hostfile.

pub fn arg(self, a: impl Into<String>) -> Self

Forward an extra CLI argument to every spawned worker (e.g. --device mlx). Workers also receive --rank i --hostfile <path>.

pub fn args<I, S>(self, it: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Forward several extra arguments at once.

pub fn capture_rank(self, rank: u32) -> Self

Which rank’s stdout to capture and return from run.

pub fn quiet(self, quiet: bool) -> Self

Suppress the one-line “spawning N ranks” banner on stderr.

pub fn run(self) -> Result<Vec<String>>

Spawn world workers, block until all exit, and return the captured rank’s stdout line by line. Errors if any worker exits non-zero.