You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: deny_single_threaded_sqlite_config.rs
    path of file: ./repos/rusqlite/tests
    
    the code of the file until where you have to start completion: //! Ensure we reject connections when SQLite is in single-threaded mode, as it
//! would violate safety if multiple Rust threads tried to use connections.

#[cfg(not(feature = "loadable_extension"))]
#[test]
fn test_error_when_singlethread_mode() {
    use rusqlite::ffi;
    use rusqlite::Connection;
    // put SQLite into single-threaded mode
    unsafe {
        // Note: macOS s
    
fn test_error_when_singlethread_mode() {
    use rusqlite::ffi;
    use rusqlite::Connection;
    // put SQLite into single-threaded mode
    unsafe {
        // Note: macOS system SQLite seems to return an error if you attempt to
        // reconfigure to single-threaded mode.
        if ffi::sqlite3_config(ffi::SQLITE_CONFIG_SINGLETHREAD) != ffi::SQLITE_OK {
            return;
        }
        assert_eq!(ffi::sqlite3_initialize(), ffi::SQLITE_OK);
    }
    let res = Connection::open_in_memory();
    res.unwrap_err();
}