Writing tests in Rust for a python extension

[Adoni5]

Hi,

Apologies for what may be a reposted question. although I had a cursory look and could not find anything. I am sure that when I was reading the docs.rs, I saw an example of how to write rust tests for your python extension, using something loosely along the lines of

     Python::with_GIL(py || {
         _example test_
    })

However I cannot for the life of me find it again. I was wondering if there was any standard way of writing these tests?

Thanks for the brilliant crate!
Rory

[davidhewitt]

Hi, sorry for the slow reply.

You can indeed write tests from Rust, you should make sure to disable the extension-module feature and instead enable the auto-initialize feature while running tests.

For some examples, see our tests we have internally for string conversions:

pyo3/src/conversions/std/string.rs

Lines 149 to 164 in 23fcdf9

	mod tests {
	use crate::Python;
	use crate::{FromPyObject, IntoPy, PyObject, ToPyObject};
	use std::borrow::Cow;
	#[test]
	fn test_cow_into_py() {
	Python::with_gil(|py| {
	let s = "Hello Python";
	let py_string: PyObject = Cow::Borrowed(s).into_py(py);
	assert_eq!(s, py_string.extract::<&str>(py).unwrap());
	let py_string: PyObject = Cow::<str>::Owned(s.into()).into_py(py);
	assert_eq!(s, py_string.extract::<&str>(py).unwrap());
	})
	}

[Adoni5]

Hi David,

Thanks for the reply and the pointer to some examples! That should do it.