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: unified_runner.rs
    path of file: ./repos/mongo-rust-driver/src/test/spec
    
    the code of the file until where you have to start completion: pub(crate) mod entity;
pub(crate) mod matcher;
pub(crate) mod observer;
pub(crate) mod operation;
pub(crate) mod test_event;
pub(crate) mod test_file;
pub(crate) mod test_runner;

use std::future::IntoFuture;

use futures::future::{BoxFuture, FutureExt};
use serde::Deserialize;

use crate::test::{file_level_log, log_uncaptured, spec::deserialize_spec_tests};

pub(crate) use self::{
    entity::{ClientEntity, Entity, SessionEntity, TestCursor},
    matcher::{events_match, results_match},
    operation::Operation,
    test_event::{ExpectedCmapEvent, ExpectedCommandEvent, ExpectedEvent, ObserveEvent},
    test_file::{
        merge_uri_options,
        CollectionData,
      
    
async fn expect_failures(spec: &[&str], skipped_files: Option<&'static [&'static str]>) {
    for (test_file_result, path) in deserialize_spec_tests::<TestFileResult>(spec, skipped_files) {
        log_uncaptured(format!("Expecting failure for {:?}", path));
        // If the test deserialized properly, then expect an error to occur during execution.
        if let TestFileResult::Ok(test_file) = test_file_result {
            std::panic::AssertUnwindSafe(async {
                TestRunner::new()
                    .await
                    .run_test(test_file, path.clone(), None)
                    .await;
            })
            .catch_unwind()
            .await
            .expect_err(&format!("Tests from {:?} should have failed", &path));
        }
    }
}