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rust.missing_select_timeout

Stability Medium

Detects tokio::select! without a timeout branch that can wait indefinitely.

Why It Matters

Select without timeout:

Indefinite waiting — Can block forever if no branch completes
Resource leaks — Held resources never released
Stuck tasks — No recovery from stalled operations

Example

// ❌ Before (no timeout)
tokio::select! {
    result = operation_a() => handle_a(result),
    result = operation_b() => handle_b(result),
}

// ✅ After (with timeout)
tokio::select! {
    result = operation_a() => handle_a(result),
    result = operation_b() => handle_b(result),
    _ = tokio::time::sleep(Duration::from_secs(30)) => {
        tracing::warn!("Operations timed out");
        return Err(Error::Timeout);
    }
}

What Unfault Detects

tokio::select! without sleep or timeout branch
Long-running selects without bounds