Hello and welcome to another issue of This Week in Rust! Rust is a programming language empowering everyone to build reliable and efficient software. This is a weekly summary of its progress and community. Want something mentioned? Tag us at @ThisWeekInRust on Twitter or @ThisWeekinRust on mastodon.social, or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community

Official

• On the RustConf keynote | Rust Blog

Project/Tooling Updates

• rumqttd now supports MQTTv5 features like topic alias and message expiry
• GlueSQL v0.14 - Schemaless data support
• ratatui 0.21.0 is released! (community fork of tui-rs)
• rust-analyzer Changelog #183
• IntelliJ Rust Changelog #195
• rustc_codegen_gcc: Progress Report #23
• Statement on RustConf & Introspection

Observations/Thoughts

• Paired benchmarking. How to measure performance
• Pattern Extensions
• A governance system, if you can keep it
• [video] Why You Shouldn’t Build Your Next App in Rust

Rust Walkthroughs

• How I finally understood async/await in Rust (part 1)
• Serving dynamic social preview images with rust and serverless functions
• Phase Locked State Machines
• ESP32 Embedded Rust at the HAL: Analog Temperature Sensing using the ADC
• [video] Atomics and Locks Book Club - Chapter 1 - Basics of Rust Concurrency
• [video] Atomics and Locks Book Club - Chapter 2 - Atomics
• [video] Deploy Rust with shuttle.rs
• [video] Building WASM web UI with Rust
• [video] A Practical Introduction to Derive Macros with Attributes
• [video] Building an HTTP Server in Rust: Exploring TCP/IP, Socket Programming, and Asynchronous I/O
• [video] Run Fast! Catch Performance Regressions in eBPF with Rust
• [video] Building a Weather Forecast Command-Line App in Rust

Miscellaneous

• I Am No Longer Speaking at RustConf 2023
• Josh Triplett's Statement on RustConf 2023
• Why I left Rust
• How s2n-quic uses Kani to inspire confidence

Crate of the Week

This week's crate is progenitor, an OpenAPI client generator with support for strongly typed mock tests.

Thanks to John Vandenberg for the suggestion!

Please submit your suggestions and votes for next week!

Call for Participation

Always wanted to contribute to open-source projects but did not know where to start? Every week we highlight some tasks from the Rust community for you to pick and get started!

Some of these tasks may also have mentors available, visit the task page for more information.

• Hyperswitch - Define the Mapping between ConnectorError and ApiErrorResponse using the ErrorSwitch trait
• Hyperswitch - Remove redundant call to fetch payment method data
• Hyperswitch - Remove redundant heap allocation (specifically string construction) in the application
• Hyperswitch - Remove redundant heap allocation present in the logging framework
• Ockam - Don't show a secure channel listener if it does not exist 2
• Ockam - ockam secure-channel-listener list --node n1 is inconsistent 2
• Ockam - Do not print that a secure channel listener was successfully deleted when it is not the case 2
• Ockam - tcp-connection show command should iter all the available nodes to find the requested ID
• Ockam - Define json output for ockam node create
• send-file - create WiFi hotspot on Linux Operating system 1
• send-file - read the device default documents directory and return an array of documents files path 1
• velo - Implement Copy and Paste Functionality for bevy_cosmic_edit - Issue #128 - StaffEngineer/velo - GitHub 2
• velo - Fix text height calculation for proper text alignment - Issue #131 - StaffEngineer/velo - GitHub 1

If you are a Rust project owner and are looking for contributors, please submit tasks here.

Updates from the Rust Project

325 pull requests were merged in the last week

• promote loongarch64-unknown-linux-gnu to Tier 2 with host tools
• enable sanitizers and profiler for aarch64-unknown-linux-musl
• add support for LLVM SafeStack
• Expand more expressions (RFC #2011)
• parse: return unpected when current token is EOF
• resolve: not defined extern crate shadow_name
• rustc_privacy: Cleanups and perf improvements to EmbargoVisitor
• add warn-by-default lint when local binding shadows exported glob re-export item
• always require closure parameters to be Sized
• check opaques for mismatch during writeback
• consider lint check attributes on match arms
• deal with unnormalized projections when structurally resolving types with new solver
• do not prefer substs relate during coherence
• don't ICE if method receiver fails to unify with arbitrary_self_types
• don't ICE on return-type notation when promoting trait preds to associated type bounds
• don't ICE when computing PointerLike trait when region vars are in param-env
• don't check for misaligned raw pointer derefs inside Rvalue::AddressOf
• don't skip mir typeck if body has errors
• enable MatchBranchSimplification
• expose more information in get_body_with_borrowck_facts
• fix for Self not respecting tuple Ctor privacy
• fix re-export of doc hidden macro not showing up
• fix some issues with folded AArch64 features
• fix symbol conflict diagnostic mistakenly being shown instead of missing crate diagnostic
• handle opaques in the new solver
• improve error message for calling a method on a raw pointer with an unknown pointee
• inline derived hash
• leverage the interval property to precompute borrow kill points
• libtest: improve error when missing -Zunstable-options
• perform MIR type ops locally in new solver
• preprocess and cache dominator tree
• pretty-print inherent projections correctly
• prevent crash when a path is not resolved in intra-doc link
• rework handling of recursive panics
• split out opaque collection from from type_of
• stop confusing specification levels when computing expectations
• use ErrorGuaranteed more in MIR type ops
• MIR: opt-in normalization of BasicBlock and Local numbering
• support #[global_allocator] without the allocator shim
• stabilize BuildHasher::hash_one
• use an unbounded lifetime in String::leak
• add Median of Medians fallback to introselect
• add #[inline] to array TryFrom impls
• add slice::{split_, }{first, last}_chunk{, _mut}
• stdarch: stabilize AArch64 AES/SHA1/SHA2 intrinsics
• regex: fix complete literal optimization issue
• cargo: add: Reduce the chance we re-format the user's [features] table
• cargo: lints: Switch to -Zlints so stable projects can experiment
• cargo: add a description of Cargo.lock conflicts in the Cargo FAQ
• cargo: automatically inherit workspace fields when running cargo new/init
• cargo: automatically inherit workspace lints when running cargo new/init
• cargo: consider rust-version when selecting packages for cargo add
• cargo: deps: remove unused features from windows-sys
• cargo: warn when an edition 2021 crate is in a virtual workspace with default resolver
• rustdoc: get unnormalized link destination for suggestions
• rustdoc-json: Use exclusively externally tagged enums in the JSON representation
• new tool rustdoc-gui-test
• clippy: default_constructed_unit_structs: do not lint on type alias paths
• clippy: large_stack_arrays: check array initializer expressions
• clippy: add needless_else lint to check for empty else clauses
• clippy: unused_async: do not consider await in nested async blocks as used
• clippy: add new lint ptr_cast_constness
• clippy: display the needless_return suggestion
• clippy: fix redundant_pattern_match on matches! macro
• clippy: fix missing block for unsafe code
• clippy: fixing invalid_regex with invalid UTF8. Also, adding more test cases
• clippy: ignore #[cfg]'d out code in needless_else
• clippy: improve pattern printing for manual_let_else
• rust-analyzer: editors/code: add markdown syntax highlighting to doc comments
• rust-analyzer: allow users to override the .scip output file path
• rust-analyzer: add diagnostic for incorrect _ expressions (typed holes)
• rust-analyzer: assist to replace generic with impl trait
• rust-analyzer: using doc aliases to search workspace symbols
• rust-analyzer: fix need-mut false positive in closure capture of match scrutinee
• rust-analyzer: add a toggle to disable the dependency explorer
• rust-analyzer: assists no longer break indentation
• rust-analyzer: change how #![cfg(FALSE)] behaves on crate root
• rust-analyzer: don't try determining type of token inside macro calls
• rust-analyzer: evaluate UnevaluatedConst in unify
• rust-analyzer: evaluate UnevaluatedConst before trait solving
• rust-analyzer: filter out unused cargo features from config
• rust-analyzer: insert type vars in function arguments
• rust-analyzer: use ::core instead of $crate in option_env!
• rust-analyzer: implement ${count()} metavariable expression

Rust Compiler Performance Triage

A good week overall, with a broad set of improvements to many primary benchmarks. The main single source of primary regressions is from rollup PR #111869; we are in the process of narrowing that down to see if there is a root cause.

Triage done by @pnkfelix. Revision range: cda5becc..1221e43b

3 Regressions, 3 Improvements, 3 Mixed; 4 of them in rollups 26 artifact comparisons made in total

Full report here

Approved RFCs

Changes to Rust follow the Rust RFC (request for comments) process. These are the RFCs that were approved for implementation this week:

• The #[diagnostic] attribute namespace

Final Comment Period

Every week, the team announces the 'final comment period' for RFCs and key PRs which are reaching a decision. Express your opinions now.

RFCs

• [disposition: merge] Return position impl Trait in traits
• [disposition: merge] eRFC: single-file packages ("cargo script") integration

Tracking Issues & PRs

• [disposition: merge] rustdoc: search for slices and arrays by type with
• [disposition: close] dyn Trait comparison should not include the vtable pointer
• [disposition: merge] Uplift clippy::fn_null_check lint
• [disposition: merge] Uplift clippy::cmp_nan lint
• [disposition: merge] rustdoc: Add search result item types after their name

New and Updated RFCs

• [new] Unsafe Extern Blocks
• [new] RFC: Implementable trait aliases
• [new] RFC: #[export] (dynamically linked crates)
• [new] Generic Futures

Call for Testing

An important step for RFC implementation is for people to experiment with the implementation and give feedback, especially before stabilization. The following RFCs would benefit from user testing before moving forward:

• Add a [lints] table to Cargo.toml (Feature: manifest-lint)
  • Tracking Issue
  • Testing steps

If you are a feature implementer and would like your RFC to appear on the above list, add the new call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

Upcoming Events

Rusty Events between 2023-05-31 - 2023-06-28 🦀

Virtual

• 2023-05-31 | Virtual (Chicago, IL, US) | Chicago Healthcare Cloud Technology Community
  • Rust for Mission-Critical AI: A Journey into Healthcare's Safest Language
• 2023-06-06 | Virtual (Austin, TX, US) | WebAssembly and WasmEdge
  • Monthly WasmEdge Community Meeting
• 2023-06-06 | Virtual (Berlin, DE) | OpenTechSchool Berlin
  • Rust Hack and Learn
• 2023-06-06 | Virtual (Buffalo, NY, US) | Buffalo Rust Meetup
  • Buffalo Rust User Group, First Tuesdays
• 2023-06-07 | Virtual (Indianapolis, IN, US) | Indy Rust
  • Indy.rs - with Social Distancing
• 2023-06-07 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2023-06-08 | Virtual (Nürnberg, DE) | Rust Nuremberg
  • Rust Nürnberg online
• 2023-06-13 | Virtual (Dallas, TX, US) | Dallas Rust
  • Second Tuesday
• 2023-06-14 | Virtual (Cardiff, UK) | Rust and C++ Cardiff
  • Building Spin Locks and Channels - Rust Atomics & Locks Bookclub Chapters 4 & 5
• 2023-06-14 | Virtual (Boulder, CO, US) | Boulder Elixir and Rust
  • Monthly Meetup
• 2023-06-15 | Virtual (Stuttgart, DE) | Rust Community Stuttgart
  • Rust-Meetup
• 2023-06-20 | Virtual (Berlin, DE) | Berline.rs / OpenTechSchool Berlin
  • Rust Hack and Learn
• 2023-06-20 | Virtual (Washington, DC, US) | Rust DC
  • Mid-month Rustful
• 2023-06-21 | Virtual (Vancouver, BC, CA) | Vancouver Rust
  • Rust Study/Hack/Hang-out
• 2023-06-25 | Virtual (Auckland, NZ) | ResBaz Aotearoa 2023
  • Research Computing With The Rust Programming Language - Tim McNamara
• 2023-06-27 | Virtual (Dallas, TX, US) | Dallas Rust
  • Last Tuesday

Asia

• 2023-06-10 | Kuala Lumpur, MY | GoLang Malaysia
  • Rust Workshop/Hack and Learn Malaysia June 2023 | Event updates Telegram | Event group chat

Europe

• 2023-06-03 | Plovidv, BG | AeroRust
  • Space Conference - Plovdiv
• 2023-06-04 | Plovidv, BG | AeroRust
  • Space Conference : Nanosatellite embedded workshop
• 2023-06-08 | Aarhus, DK | Rust Aarhus
  • Rust Aarhus meetup #2 sponsored by BRØLSTÆRK
• 2023-06-08 | Paris, FR | Stockly.ai
  • Rust Meetup in Paris - hosted by Stockly
• 2023-06-08 | Zurich, CH | Rust Zurich
  • Unsafe, Miri, SIMD - June Meetup
• 2023-06-16 | Stuttgart, DE | Rust Community Stuttgart
  • OnSite Meeting
• 2023-06-28 | Bratislava, SK | Bratislava Rust Meetup Group
  • Rust Meetup by Sonalake

North America

• 2023-06-01 | Mountain View, CA, US | Mountain View Rust Meetup
  • Rust Meetup at Hacker Dojo
• 2023-06-01 | Pasadena, CA, US | Pasadena Thursday Go / Rust
  • Weekly leetcode group (Go and Rust)
• 2023-06-07 | Austin, TX, US | Rust ATX
  • Rust Lunch
• 2023-06-08 | Lehi, UT, US | Utah Rust
  • Rust 1.70.0, Module System Deep Dive & Pizza

If you are running a Rust event please add it to the calendar to get it mentioned here. Please remember to add a link to the event too. Email the Rust Community Team for access.

Jobs

Please see the latest Who's Hiring thread on r/rust

Quote of the Week

Panics are overgrown ASSERTs, not an underbuilt exception system.

– Stephan Sokolow on hacker news

Thanks to Stephan Sokolow for the self-suggestion!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, andrewpollack, U007D, kolharsam, joelmarcey, mariannegoldin, bennyvasquez.

Email list hosting is sponsored by The Rust Foundation

Discuss on r/rust