Making a CLI REPL

[OriDevTeam]

I attempted to essentially just re-emulate the normal python interpreter behavior that happens when doing the simple python but in a binary with Pyo3, the reasoning for is that i can use it to test functions that the binary has by having the same REPL behavior, lets say the binary has a foo module with a bar function and all i want to do is import foo then foo.bar() and do all the eval typical things, issue is that probably this is not the best approach:

pub fn create_interpreter() -> PyResult<()> {
    let interp = Python::with_gil(|py| {
        let sys = py.import("sys")?;
        let version: String = sys.getattr("version")?.extract()?;

        let locals = [("os", py.import("os")?)].into_py_dict(py);
        let code = "os.getenv('USER') or os.getenv('USERNAME') or 'Unknown'";
        let user: String = py.eval(code, None, Some(&locals))?.extract()?;

        println!("Hello {}, I'm Python {}", user, version);

        loop {
            print!(">>> ");
            
            let mut input = String::new();
            match io::stdin().read_line(&mut input) {
                Ok(_) => {
                    let r = py.run(&input, None, None);
                    if r.is_err() { println!("{}", r.err().unwrap()); }
                }
                Err(e) => { println!("{e}")}
            };
        }
    });

    interp
}

And this is how it behaves ( yes i also failed to emulate the >>> behavior properly and more )

What would be the proper approach to this?

[OriDevTeam]

After asking for some help to some rust folks, they found out that Python's module which essentially is most of the REPL behavior.

Here follows the solution code:

pub fn create_interpreter() -> PyResult<()> {
    let interp = Python::with_gil(|py| {
        let sys = py.import("sys")?;
        let version: String = sys.getattr("version")?.extract()?;

        let locals = [("os", py.import("os")?)].into_py_dict(py);
        let code = "os.getenv('USER') or os.getenv('USERNAME') or 'Unknown'";
        let user: String = py.eval(code, None, Some(&locals))?.extract()?;

        println!("Hello {}, I'm Python {}", user, version);

        py.run("import code; code.interact('')", None, None)
    });

    interp
}

Resulting in the intended

Now for some takes on the matter,
I did not sure confirmation but i presume the behavior of is to either call this code or do something similar.

I think it would be good that this could be addressed to implementation on Pyo3, and possibly addressed in the docs, as i took some time to find a solution for it and personally its a case i come across often enough to be face-value documented

There is also entry-points which can also be beneficial to have which some of them are here https://docs.python.org/3/c-api/veryhigh.html