notescraft/crates/vault/tests/sibling.rs

//! `Vault::sibling`: a second handle without the lock, for worker threads of the holder.

mod common;

use std::time::Duration;

use notescraft_vault::{Vault, VaultEvent, WriteOutcome};

/// Compile-time proof that a `Vault` may travel to a worker thread.
#[allow(dead_code)]
fn assert_send<T: Send>() {}
const _: fn() = || assert_send::<Vault>();

#[test]
fn a_sibling_writes_while_the_parent_holds_the_lock() {
    let (_dir, parent) = common::vault("sibling");
    let watcher = parent.watch().expect("watch the vault");

    let sibling = parent.sibling();
    assert!(!sibling.is_read_only());
    assert_eq!(sibling.root(), parent.root());
    assert_eq!(sibling.write("sib.md", b"hello").unwrap(), WriteOutcome::Written);

    // The parent reads what the sibling wrote, and its watcher reports the write.
    assert_eq!(common::read(&parent, "sib.md"), b"hello");
    let event = watcher.receiver().recv_timeout(Duration::from_secs(5)).expect("an event");
    let hit = matches!(&event, VaultEvent::Created(path) | VaultEvent::Modified(path) if path == "sib.md");
    assert!(hit, "the watcher should see the sibling's write: {event:?}");
}

#[test]
fn a_sibling_of_a_read_only_vault_is_read_only() {
    let dir = common::TempDir::new("sibling-ro");
    let parent = Vault::open_read_only(dir.path()).expect("open read-only");
    let sibling = parent.sibling();
    assert!(sibling.is_read_only());
    assert!(sibling.write("x.md", b"y").is_err());
}