Back to all reviewers

Write focused single-purpose tests

tokio-rs/tokio
Based on 8 comments
Rust

Break down large test cases into smaller, focused tests that each verify a single feature or behavior. Each test should have a clear purpose that is evident from its name and structure. This improves test maintainability, readability, and makes failures easier to debug.

Testing Rust

Reviewer Prompt

Break down large test cases into smaller, focused tests that each verify a single feature or behavior. Each test should have a clear purpose that is evident from its name and structure. This improves test maintainability, readability, and makes failures easier to debug.

Instead of combining multiple test cases:

#[test]
fn test_channel_behavior() {
    let (tx, rx) = channel();
    // Test multiple behaviors...
    assert!(rx.is_empty());
    tx.send(1).unwrap();
    assert!(!rx.is_empty());
    drop(tx);
    assert!(rx.is_closed());
}

Break it into focused tests:

#[test]
fn is_empty_returns_true_initially() {
    let (_, rx) = channel();
    assert!(rx.is_empty());
}

#[test]
fn is_empty_returns_false_after_send() {
    let (tx, rx) = channel();
    tx.send(1).unwrap();
    assert!(!rx.is_empty());
}

#[test]
fn is_closed_returns_true_after_sender_drop() {
    let (tx, rx) = channel();
    drop(tx);
    assert!(rx.is_closed());
}

Key benefits:

  • Clear test purpose and failure diagnosis
  • Better coverage tracking
  • Easier maintenance and updates
  • Simpler debugging when tests fail
  • More meaningful test names
8
Comments Analyzed
Rust
Primary Language
Testing
Category

Source Discussions