Summary

A module-level __dir__ function (PEP 562) is ignored: dir(module) returns the raw __dict__ keys instead of calling the module's __dir__.

# mod.py
import sys

def __dir__():
    return ['gamma', 'alpha', 'beta']

print(dir(sys.modules[__name__]))

• CPython 3.14.2: ['alpha', 'beta', 'gamma'] (calls the function, dir() sorts the result)
• RustPython: ['__builtins__', '__cached__', '__dir__', ..., 'sys']

Verified on main @ 7044fdc. PEP 562's other half, module-level __getattr__, works — only __dir__ is missing.

Cause

PyModule.__dir__ (crates/vm/src/builtins/module.rs:300) unconditionally returns the module dict's keys:

fn __dir__(zelf: &Py<Self>, vm: &VirtualMachine) -> PyResult<Vec<PyObjectRef>> {
    let dict_attr = zelf.as_object().get_attr(identifier!(vm, __dict__), vm)?;
    ...
    Ok(dict.into_iter().map(|(k, _v)| k).collect())
}

CPython's module___dir___impl (Objects/moduleobject.c) first looks up __dir__ in the module's __dict__ and, if present, calls it and returns its result; only otherwise does it fall back to list(__dict__).

Found while running synthetic benchmark/compat suites; researched and reported by Claude on behalf of @youknowone.