musefs-db 1.2.0

use musefs_db::Db;

#[test]
fn open_in_memory_runs_migration_to_latest() {
    let db = Db::open_in_memory().expect("open");
    assert_eq!(db.user_version().expect("user_version"), 2);
}

#[test]
fn migration_is_idempotent_across_reopen() {
    let dir = tempfile::tempdir().unwrap();
    let path = dir.path().join("musefs.db");

    let db = Db::open(&path).unwrap();
    assert_eq!(db.user_version().unwrap(), 2);
    drop(db);

    // Reopening must not error and must not advance the version.
    let db2 = Db::open(&path).unwrap();
    assert_eq!(db2.user_version().unwrap(), 2);
}

#[test]
fn opening_a_store_newer_than_the_binary_fails_loudly() {
    let dir = tempfile::tempdir().unwrap();
    let path = dir.path().join("musefs.db");

    // Create a normal store, then simulate a future/third-party tool bumping the
    // schema past what this binary knows about.
    Db::open(&path).unwrap();
    {
        let conn = rusqlite::Connection::open(&path).unwrap();
        conn.pragma_update(None, "user_version", 3).unwrap();
    }

    // Reopening must refuse the store instead of silently treating it as
    // already-migrated and risking a misread of the external-writer contract.
    let err = Db::open(&path).unwrap_err();
    assert!(
        matches!(
            err,
            musefs_db::DbError::StoreTooNew {
                found: 3,
                supported: 2
            }
        ),
        "expected StoreTooNew {{ found: 3, supported: 2 }}, got {err:?}"
    );
}

#[cfg(feature = "mutants")]
#[test]
fn default_db_is_unmigrated_version_zero() {
    // Kills `Db::user_version -> Ok(1)`: Default opens an UNMIGRATED in-memory
    // connection, so user_version is 0, distinct from the always-migrated 2.
    let db = Db::default();
    assert_eq!(db.user_version().unwrap(), 0);
}