Is it okay to skip async_drop during a panic?

Yes, the pattern generally treats panics as exceptions where skipping async_drop is acceptable to avoid double-panics during stack unwinding.

Can I use this for shared resources like Arc?

Yes, the skill includes implementation patterns for helper types like AsyncDropArc to handle shared ownership of resources requiring async cleanup.

What happens if I forget to call async_drop()?

The AsyncDropGuard is designed to panic if it is destroyed without its async_drop() method being called, ensuring that resource leaks are caught during development.

Why do I need AsyncDrop in Rust?

Rust's native Drop trait is synchronous, which makes it difficult to perform cleanup tasks that require .await, such as closing network sockets or flushing data to a cloud filesystem.

How does the with_async_drop_2! macro help?

This macro automatically handles the async_drop() call on scope exit, providing a safer and less verbose way to manage resources compared to manual guard management.

Rust AsyncDrop Pattern Guide

Name: Rust AsyncDrop Pattern Guide
Author: cryfs

bycryfs

•

2,192

Learning & Documentation

Implements and manages asynchronous resource cleanup patterns in Rust using specialized guards and traits.

About

The AsyncDrop skill provides a standardized framework for handling asynchronous cleanup in Rust applications, addressing the inherent limitations of Rust's synchronous Drop trait. By leveraging the AsyncDropGuard pattern and the AsyncDrop trait, it ensures that resources requiring asynchronous teardown—such as network connections, file handles, and background tasks—are properly closed before destruction. This skill is essential for developers working on high-reliability Rust systems where silent resource leaks must be prevented through explicit cleanup enforcement and safety macros.

Key Features

Automated cleanup scope management using the with_async_drop_2! macro
Standardized AsyncDrop trait for custom asynchronous cleanup implementations
AsyncDropGuard wrapper to enforce explicit resource teardown via .await calls
Safety enforcement mechanisms that panic if resources are dropped without cleanup
Support for complex resource types including AsyncDropArc and AsyncDropHashMap
2,192 GitHub stars

Use Cases

Ensuring database transactions are flushed and closed asynchronously before scope exit
Managing network connection teardowns that require asynchronous closing handshakes
Implementing safe background task termination where a task must be awaited during shutdown

About

Key Features

Automated cleanup scope management using the with_async_drop_2! macro
Standardized AsyncDrop trait for custom asynchronous cleanup implementations
AsyncDropGuard wrapper to enforce explicit resource teardown via .await calls
Safety enforcement mechanisms that panic if resources are dropped without cleanup
Support for complex resource types including AsyncDropArc and AsyncDropHashMap
2,192 GitHub stars

Use Cases

Ensuring database transactions are flushed and closed asynchronously before scope exit
Managing network connection teardowns that require asynchronous closing handshakes
Implementing safe background task termination where a task must be awaited during shutdown