Write async tests in Rust by adding the tokio dependency and using the #[tokio::test] attribute on your async functions.
Use the #[tokio::test] attribute to run async functions as tests, requiring the tokio crate with the test-util feature. Add tokio = { version = "1", features = ["full"] } to your Cargo.toml and mark your async test function with the attribute.
#[tokio::test]
async fn async_test_example() {
let result = 2 + 2;
assert_eq!(result, 4);
}
Async tests let you verify code that waits for things like network requests or file reads without freezing your computer. You use a special marker to tell the test runner to handle the waiting logic automatically. Think of it like a supervisor who knows how to pause and resume tasks so they finish correctly.