Prepare for pyo3 0.26

[kylebarron]

It looks like a release of pyo3 0.26 is imminent.

• Replace Python::with_gil with Python::attach.
• Replace pyo3::prepare_freethreaded_python(); with Python::initialize();
• Replace PyObject with Py<PyAny>
• Bump MSRV to 1.74

This uses the git tag for pyo3 0.26 at the moment and will switch to the official crates.io version when 0.26 is published.

cc @davidhewitt

[davidhewitt]

Thanks, yep just waiting to fix some issues with trusted publishing and then hopefully the crates.io release will be live shortly!

Once I have it working, I'll send a PR here to configure trusted publishing too.

Just spotted a few things in this code where we can apply some TLC as we upgrade...

[davidhewitt]

I think these should probably be updated to use the new PyOnceLock (and PyOnceLock::import, potentially).

[kylebarron]

60b735d (#54)

There are still some uses of OnceCell:

pyo3-async-runtimes/src/tokio.rs

Line 69 in 74cd232

static TOKIO_RUNTIME: OnceCell<Pyo3Runtime> = OnceCell::new();

We could change them but then we'd also have to change the signatures of these public functions init_with_runtime, get_runtime, etc, to have a py: Python argument.

pyo3-async-runtimes/src/tokio.rs

Lines 182 to 186 in 74cd232

	pub fn init_with_runtime(runtime: &'static Runtime) -> Result<(), ()> {
	TOKIO_RUNTIME
	.set(Pyo3Runtime::Borrowed(runtime))
	.map_err(|_| ())
	}

[davidhewitt]

Ah yes, these ones which don't need Python can probably now be replaced with std::sync::OnceLock, which is available after we bump MSRV.

[kylebarron]

I was able to remove almost all uses of once_cell, except for

pyo3-async-runtimes/src/tokio.rs

Line 68 in 5e6c5b7

static TOKIO_BUILDER: Lazy<Mutex<Builder>> = Lazy::new(|| Mutex::new(multi_thread()));

since it looks like LazyLock wasn't added to the stdlib until an MSRV of 1.80.

[kylebarron]

Can you shed some light on whether the CI failure is real?

Run cargo add tokio@=1.38.1
    Updating crates.io index
      Adding tokio =1.38.1 to optional dependencies.
             Features:
             + num_cpus
             + rt
             + rt-multi-thread
             + time
             - bytes
             - fs
             - full
             - io-std
             - io-util
             - libc
             - macros
             - mio
             - net
             - parking_lot
             - process
             - signal
             - signal-hook-registry
             - socket2
             - sync
             - test-util
             - tokio-macros
             - tracing
             - windows-sys
    Updating crates.io index
error: failed to select a version for the requirement `once_cell = "^1.21"`
candidate versions found which didn't match: 1.20.3
location searched: crates.io index
required by package `pyo3 v0.26.0`
    ... which satisfies dependency `pyo3 = "^0.26"` (locked to 0.26.0) of package `pyo3-async-runtimes v0.26.0 (/home/runner/work/pyo3-async-runtimes/pyo3-async-runtimes)`

It looks like the MSRV of pyo3 is now 1.74, while the MSRV of pyo3-async-runtimes is 1.63. Should we bump the MSRV here to match 1.74?

[davidhewitt]

Ah yes, let's bump MSRV to 1.74 to match 👍

[alex]

Let me know if there's anything I can do to help get this merged!

[davidhewitt]

Trusted publishing and 3.14 support is now done in #55

[kylebarron]

It looks like this is ready for merge! @davidhewitt

[davidhewitt]

Great! I think I spotted one simplification, will push a commit and merge

[davidhewitt]

Released, thanks all!