Merge pull request #886 from fusion-engineering-forks/dir

Add dir() to ObjectProtocol.

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
 * `_PyDict_NewPresized`. [#849](https://github.com/PyO3/pyo3/pull/849)
 * `IntoPy<PyObject>` for `HashSet` and `BTreeSet`. [#864](https://github.com/PyO3/pyo3/pull/864)
+* `ObjectProtocol::dir`. [#886](https://github.com/PyO3/pyo3/pull/886)
 
 ### Fixed
 * `__radd__` and other `__r*__` methods now correctly work with operators. [#839](https://github.com/PyO3/pyo3/pull/839)

src/objectprotocol.rs

@@ -3,7 +3,7 @@
 use crate::class::basic::CompareOp;
 use crate::err::{self, PyDowncastError, PyErr, PyResult};
 use crate::exceptions::TypeError;
-use crate::types::{PyAny, PyDict, PyIterator, PyString, PyTuple, PyType};
+use crate::types::{PyAny, PyDict, PyIterator, PyList, PyString, PyTuple, PyType};
 use crate::{
     ffi, AsPyPointer, FromPyObject, IntoPy, IntoPyPointer, Py, PyNativeType, PyObject, PyTryFrom,
     Python, ToBorrowedObject, ToPyObject,
@@ -212,6 +212,9 @@ pub trait ObjectProtocol {
     /// Returns the reference count for the Python object.
     fn get_refcnt(&self) -> isize;
 
+    /// Returns the list of attributes of this object.
+    fn dir(&self) -> &PyList;
+
     /// Gets the Python builtin value `None`.
     #[allow(non_snake_case)] // the Python keyword starts with uppercase
     fn None(&self) -> PyObject;
@@ -485,6 +488,10 @@ where
         unsafe { ffi::Py_REFCNT(self.as_ptr()) }
     }
 
+    fn dir(&self) -> &PyList {
+        unsafe { self.py().from_owned_ptr(ffi::PyObject_Dir(self.as_ptr())) }
+    }
+
     #[allow(non_snake_case)] // the Python keyword starts with uppercase
     fn None(&self) -> PyObject {
         unsafe { PyObject::from_borrowed_ptr(self.py(), ffi::Py_None()) }
@@ -545,4 +552,22 @@ mod test {
         let obj = py.eval("42", None, None).unwrap();
         assert_eq!(unsafe { obj.get_type().as_type_ptr() }, obj.get_type_ptr())
     }
+
+    #[test]
+    fn test_dir() {
+        let gil = Python::acquire_gil();
+        let py = gil.python();
+        let obj = py.eval("42", None, None).unwrap();
+        let dir = py
+            .eval("dir(42)", None, None)
+            .unwrap()
+            .extract::<&PyList>()
+            .unwrap();
+        let a = obj
+            .dir()
+            .into_iter()
+            .map(|x| x.extract::<String>().unwrap());
+        let b = dir.into_iter().map(|x| x.extract::<String>().unwrap());
+        assert!(a.eq(b));
+    }
 }