rsynko-process 0.1.0

//! The process interpreter, run against a stated program rather than a transfer.
//!
//! What a transfer means is checked by the specification's own laws. What is checked here is only
//! what this crate decides: that a line ends at a newline or a carriage return, that every line
//! reaches whoever is watching, and that a program refusing its work is stated as a refusal.

use rsynko_manager::{ChangeKind, PlannedChangeAlg};
use rsynko_memory::{SyncCommand, SyncObservation};
use rsynko_process::{ProcessSyncEnv, ProcessSyncError};
use rsynko_rsync::SyncProgramExt;
use std::sync::mpsc::channel;

/// States one program the interpreter runs in place of a transfer.
fn stated(script: &str) -> SyncCommand {
    SyncCommand {
        program: "/bin/sh".to_owned(),
        arguments: vec!["-c".to_owned(), script.to_owned()],
    }
}

#[test]
fn progress_and_changes_arrive_however_the_program_ends_its_lines() {
    let (sender, watched) = channel();
    let environment = ProcessSyncEnv::new(sender);
    // Progress is written over itself with carriage returns; itemized paths end with newlines.
    let command = stated(
        r"printf '>f+++++++++|4|new.txt\n    19,084,083  28%%   2.02MB/s\r*deleting  |0|gone.txt\n'",
    );

    let changes = environment.run_sync(&command).expect("stated program runs");

    let named = changes
        .iter()
        .map(|change| {
            (
                change.change_path(),
                change.change_kind(),
                change.change_size(),
            )
        })
        .collect::<Vec<_>>();
    assert_eq!(
        named,
        vec![
            ("new.txt", ChangeKind::Create, Some(4)),
            // A removal states no size: the transfer never looked at what it holds.
            ("gone.txt", ChangeKind::Delete, None),
        ]
    );
    let observed = watched.try_iter().collect::<Vec<_>>();
    assert!(observed.iter().any(|observation| matches!(
        observation,
        SyncObservation::Progress {
            transferred: 19_084_083,
            percent: 28
        }
    )));
    assert_eq!(observed.len(), 3);
}

#[test]
fn a_program_that_refuses_states_why() {
    let (sender, _watched) = channel();
    let environment = ProcessSyncEnv::new(sender);
    let command = stated("echo 'rsync: connection unexpectedly closed' >&2; exit 12");

    let refusal = environment
        .run_sync(&command)
        .expect_err("the stated program refuses");

    match refusal {
        ProcessSyncError::Refused(reason) => {
            assert_eq!(reason, "rsync: connection unexpectedly closed");
        }
        other => panic!("a refusing program states {other}"),
    }
}

#[test]
fn a_program_that_does_not_exist_is_not_a_refusal() {
    let (sender, _watched) = channel();
    let environment = ProcessSyncEnv::new(sender);
    let command = SyncCommand {
        program: "rsynko-no-such-program".to_owned(),
        arguments: Vec::new(),
    };

    let refusal = environment
        .run_sync(&command)
        .expect_err("an absent program cannot run");

    assert!(matches!(refusal, ProcessSyncError::Unstartable(_)));
}