youknowdot 7d15b50cd4 Align weak-reference collection with Python 3.15 finalization (#9168)
* Align weak-reference collection with Python 3.15 finalization

Trace and retain owned callback edges independently of weak referent links.
Clear callback-bearing weakrefs before finalizers, suppress callbacks from
unreachable weakrefs, and close remaining weakref ingress after resurrection
checks while the world is stopped. Publish and unlink intrusive nodes safely.

Refresh weakref and canonical weakref/GC/finalization tests through update_lib
from pinned CPython 3.15.0. Retire four obsolete guards only after fresh body
passes, retaining applicable RustPython limitations.

Assisted-by: OpenAI Codex:model version unavailable

* Refresh canonical IO tests for weakref finalization

Migrate the complete CPython 3.15.0 test_io package at d220409 with the
fail-closed legacy-map updater, preserving all ten existing guards. Retire
the seven consolidated standalone suites and update io/file dependency
paths with mapping regression tests.

The canonical GC tests ignore ResourceWarning without retaining its
source, so callback-free weakrefs correctly reflect surviving owners.
This closes the stale test dependency exposed by the lifecycle change.

Assisted-by: OpenAI Codex:model version unavailable

* Protect weakref callbacks with the original referent stripe

Follow CPython's free-threading weakref locking model instead of keeping
an independent callback RwLock. Retain the original referent stripe key
so callback access stays synchronized after GC clears the referent.
Unlink and steal callbacks under that stripe, then release ownership
outside the lock. Preserve synchronization for running-world GC paths
and gc.get_referents while keeping ordinary weakref upgrades unchanged.

Assisted-by: OpenAI Codex:model version unavailable

* Defer weakref GC tracking until referent publication

Keep freshly allocated weakrefs out of GC's object lists until they are
linked and their referent is published. Release the referent stripe before
tracking, since tracking can collect and invoke finalizers. Generic reuse
losers remain untracked.

Exercise the allocator boundary directly for reference, proxy, callable
proxy and subclass payloads, and ensure completed constructors track their
objects. This prevents observers from retaining a half-built dead weakref
that later becomes live.

Assisted-by: OpenAI Codex:model version unavailable

* Retain the original weakref stripe lock like CPython

Store a safe handle to the selected static weakref stripe instead of
retaining and rehashing the referent address. Keep the same lock after
referent clearing, matching CPython free-threaded weakrefs_lock. The
nonthreaded handle is zero-sized and introduces no locking.

Preserve lock selection, acquire/release ordering, fork reset, deferred
GC publication, and callback-owner release outside the stripe. No new
locks or unsafe code are needed.

Assisted-by: OpenAI Codex:model version unavailable
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RustPython

A Python-3 (CPython >= 3.15.0) Interpreter written in Rust 🐍 😱 🤘.

Build Status codecov CodSpeed License: MIT Contributors Discord Shield docs.rs Crates.io dependency status Open in Gitpod

Usage

Check out our online demo running on WebAssembly.

RustPython requires Rust latest stable version (e.g 1.67.1 at February 7th 2023). If you don't currently have Rust installed on your system you can do so by following the instructions at rustup.rs.

To check the version of Rust you're currently running, use rustc --version. If you wish to update, rustup update stable will update your Rust installation to the most recent stable release.

To build RustPython locally, first, clone the source code:

git clone https://github.com/RustPython/RustPython

RustPython uses symlinks to manage python libraries in Lib/. If on windows, running the following helps:

git config core.symlinks true

Then you can change into the RustPython directory and run the demo (Note: --release is needed to prevent stack overflow on Windows):

$ cd RustPython
$ cargo run --release -- -c 'print("Hello, RustPython!")'
Hello, RustPython!

Or use the interactive shell:

$ cargo run --release
Welcome to rustpython
>>>>> 2+2
4

NOTE: For windows users, please set RUSTPYTHONPATH environment variable as Lib path in project directory. (e.g. When RustPython directory is C:\RustPython, set RUSTPYTHONPATH as C:\RustPython\Lib)

You can also install and run RustPython with the following:

$ cargo install --git https://github.com/RustPython/RustPython rustpython
$ rustpython
Welcome to the magnificent Rust Python interpreter
>>>>>

venv

Because RustPython currently doesn't provide a well-packaged installation, using venv helps to use pip easier.

$ rustpython -m venv <your_env_name>
$ . <your_env_name>/bin/activate
$ python # now `python` is the alias of the RustPython for the new env

PIP

If you'd like to make https requests, you can enable the ssl feature, which also lets you install the pip package manager. Note that on Windows, you may need to install OpenSSL, or you can enable the ssl-openssl-vendor feature instead, which compiles OpenSSL for you but requires a C compiler, perl, and make. OpenSSL version 3 is expected and tested in CI. Older versions may not work.

Once you've installed rustpython with SSL support, you can install pip by running:

cargo install --git https://github.com/RustPython/RustPython
rustpython --install-pip

You can also install RustPython through the conda package manager, though this isn't officially supported and may be out of date:

conda install rustpython -c conda-forge
rustpython

SSL provider

For HTTPS requests, ssl-rustls-aws-lc is enabled by default for the RustPython binary. Embedders can use rustpython-stdlib's provider-agnostic ssl-rustls feature and install their own rustls crypto provider, or replace rustls with ssl-openssl if their environment requires OpenSSL. Note that to use OpenSSL on Windows, you may need to install OpenSSL, or you can enable the ssl-openssl-vendor feature instead, which compiles OpenSSL for you but requires a C compiler, perl, and make. OpenSSL version 3 is expected and tested in CI. Older versions may not work.

WASI

You can compile RustPython to a standalone WebAssembly WASI module so it can run anywhere.

Build

cargo build --target wasm32-wasip1 --no-default-features --features freeze-stdlib,stdlib --release

Run by wasmer

wasmer run --volume `pwd` -- target/wasm32-wasip1/release/rustpython.wasm `pwd`/extra_tests/snippets/stdlib_random.py

Run by wapm

$ wapm install rustpython
$ wapm run rustpython
>>>>> 2+2
4

Building the WASI file

You can build the WebAssembly WASI file with:

cargo build --release --target wasm32-wasip1 --features="freeze-stdlib"

Note: we use the freeze-stdlib to include the standard library inside the binary. You also have to run once rustup target add wasm32-wasip1.

JIT (Just in time) compiler

RustPython has a very experimental JIT compiler that compile python functions into native code.

Building

By default the JIT compiler isn't enabled, it's enabled with the jit cargo feature.

cargo run --features jit

This requires autoconf, automake, libtool, and clang to be installed.

Using

To compile a function, call __jit__() on it.

def foo():
    a = 5
    return 10 + a


foo.__jit__()  # this will compile foo to native code and subsequent calls will execute that native code
assert foo() == 15

Embedding RustPython into your Rust Applications

Interested in exposing Python scripting in an application written in Rust, perhaps to allow quickly tweaking logic where Rust's compile times would be inhibitive? Then examples/hello_embed.rs and examples/mini_repl.rs may be of some assistance.

Disclaimer

RustPython is in development, and while the interpreter certainly can be used in interesting use cases like running Python in WASM and embedding into a Rust project, do note that RustPython is not totally production-ready.

Contribution is more than welcome! See our contribution section for more information on this.

Conference videos

Checkout those talks on conferences:

Use cases

Although RustPython is a fairly young project, a few people have used it to make cool projects:

  • GreptimeDB: an open-source, cloud-native, distributed time-series database. Using RustPython for embedded scripting.
  • pyckitup: a game engine written in rust.
  • Robot Rumble: an arena-based AI competition platform
  • Ruff: an extremely fast Python linter, written in Rust

Goals

  • Full Python-3 environment entirely in Rust (not CPython bindings)
  • A clean implementation without compatibility hacks

Documentation

Currently along with other areas of the project, documentation is still in an early phase.

You can read the online documentation for the latest release, or the user guide.

You can also generate documentation locally by running:

cargo doc # Including documentation for all dependencies
cargo doc --no-deps --all # Excluding all dependencies

Documentation HTML files can then be found in the target/doc directory or you can append --open to the previous commands to have the documentation open automatically on your default browser.

For a high level overview of the components, see the architecture document.

Contributing

Contributions are welcome and highly appreciated. To get started, check out the contributing guidelines.

You can also join us on Discord.

Compiling to WebAssembly

See this doc

Community

Discord Banner

Chat with us on Discord.

Code of conduct

Our code of conduct can be found here.

Credit

The initial work was based on windelbouwman/rspython and shinglyu/RustPython

These are some useful links to related projects:

License

This project is licensed under the MIT license. Please see the LICENSE file for more details.

The project logo is licensed under the CC-BY-4.0 license. Please see the LICENSE-logo file for more details.

Languages
Rust 87.1%
Python 12.4%
JavaScript 0.2%
NSIS 0.2%