Attribute Macro pymethods

#[pymethods]

pyo3::pymethods with async support.

For each async methods, generate a additional function prefixed by async_, decorated with #[pyo3(name = ...)]. Original async methods are kept in a separate impl, while the original impl is decorated with pyo3::pymethods.

Python async backend can be specified using macro argument (default to asyncio). If allow_threads is passed in arguments, GIL will be released for future polling (see AllowThreads)

Example

#[pyo3::pyclass]
struct Counter(usize);

#[pyo3_async::pymethods(trio)]
impl Counter {
    fn incr_sync(&mut self) -> usize {
        self.0 += 1;
        self.0
    }

    // Arguments needs to implement `Send + 'static`, so `self` must be passed using `Py<Self>`
    async fn incr_async(self_: pyo3::Py<Self>) -> pyo3::PyResult<usize> {
        pyo3::Python::with_gil(|gil| {
            let mut this = self_.borrow_mut(gil);
            this.0 += 1;
            Ok(this.0)
        })
    }
}

generates

#[pyo3::pyclass]
struct Counter(usize);

#[::pyo3::pymethods]
impl Counter {
    fn incr_sync(&mut self) -> usize {
        self.0 += 1;
        self.0
    }

    #[pyo3(name = "incr_async")]
    fn async_incr_async(self_: pyo3::Py<Self>) -> ::pyo3_async::trio::Coroutine {
        ::pyo3_async::trio::Coroutine::from_future(Counter::incr_async(self_))
    }
}
impl Counter {
    async fn incr_async(self_: pyo3::Py<Self>) -> pyo3::PyResult<usize> {
        pyo3::Python::with_gil(|gil| {
            let mut this = self_.borrow_mut(gil);
            this.0 += 1;
            Ok(this.0)
        })
    }
}