Complete __dict__ support

CHANGELOG.md

@@ -47,6 +47,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Fixed
 
  * A soudness hole where every instances of a `#[pyclass]` struct was considered to be part of a python object, even though you can create instances that are not part of the python heap. This was fixed through `PyRef` and `PyRefMut`. 
+ * Fix kwargs support in [#328].
+ * Add full support for `__dict__` in [#403].
 
 ## [0.5.3] - 2019-01-04
 

guide/src/class.md

@@ -104,8 +104,7 @@ python object that can be collected, the `PyGCProtocol` trait has to be implemen
 * `weakref` - adds support for python weak references
 * `extends=BaseType` - use a custom base class. The base BaseType must implement `PyTypeInfo`.
 * `subclass` - Allows Python classes to inherit from this class
-* `dict` - adds `__dict__` support, the instances of this type have a dictionary containing instance variables. (Incomplete, see [#123](https://github.com/PyO3/pyo3/issues/123))
-
+* `dict` - adds `__dict__` support, the instances of this type have a dictionary containing instance variables.
 
 ## Constructor
 

src/ffi2/descrobject.rs

@@ -27,6 +27,8 @@ pub const PyGetSetDef_INIT: PyGetSetDef = PyGetSetDef {
     closure: ptr::null_mut(),
 };
 
+pub const PyGetSetDef_DICT: PyGetSetDef = PyGetSetDef_INIT;
+
 impl Clone for PyGetSetDef {
     #[inline]
     fn clone(&self) -> PyGetSetDef {

src/ffi3/descrobject.rs

@@ -1,5 +1,7 @@
 use crate::ffi3::methodobject::PyMethodDef;
-use crate::ffi3::object::{PyObject, PyTypeObject};
+use crate::ffi3::object::{
+    PyObject, PyObject_GenericGetDict, PyObject_GenericSetDict, PyTypeObject,
+};
 use crate::ffi3::structmember::PyMemberDef;
 use std::os::raw::{c_char, c_int, c_void};
 use std::ptr;
@@ -27,6 +29,14 @@ pub const PyGetSetDef_INIT: PyGetSetDef = PyGetSetDef {
     closure: ptr::null_mut(),
 };
 
+pub const PyGetSetDef_DICT: PyGetSetDef = PyGetSetDef {
+    name: "__dict__\0".as_ptr() as *mut c_char,
+    get: Some(PyObject_GenericGetDict),
+    set: Some(PyObject_GenericSetDict),
+    doc: ptr::null_mut(),
+    closure: ptr::null_mut(),
+};
+
 #[cfg_attr(windows, link(name = "pythonXY"))]
 extern "C" {
     pub static mut PyClassMethodDescr_Type: PyTypeObject;

src/ffi3/object.rs

@@ -702,6 +702,7 @@ extern "C" {
         arg2: *mut PyObject,
         arg3: *mut PyObject,
     ) -> c_int;
+    pub fn PyObject_GenericGetDict(arg1: *mut PyObject, arg2: *mut c_void) -> *mut PyObject;
     pub fn PyObject_GenericSetDict(
         arg1: *mut PyObject,
         arg2: *mut PyObject,

src/type_object.rs

@@ -321,7 +321,8 @@ where
     }
 
     // __dict__ support
-    if T::FLAGS & PY_TYPE_FLAG_DICT != 0 {
+    let has_dict = T::FLAGS & PY_TYPE_FLAG_DICT != 0;
+    if has_dict {
         offset -= std::mem::size_of::<*const ffi::PyObject>();
         type_object.tp_dictoffset = offset as isize;
     }
@@ -392,6 +393,10 @@ where
 
     // properties
     let mut props = py_class_properties::<T>();
+
+    if cfg!(Py_3) && has_dict {
+        props.push(ffi::PyGetSetDef_DICT);
+    }
     if !props.is_empty() {
         props.push(ffi::PyGetSetDef_INIT);
         type_object.tp_getset = Box::into_raw(props.into_boxed_slice()) as *mut _;

tests/test_dunder.rs

@@ -453,6 +453,22 @@ fn dunder_dict_support() {
     );
 }
 
+#[cfg(Py_3)]
+#[test]
+fn access_dunder_dict() {
+    let gil = Python::acquire_gil();
+    let py = gil.python();
+    let inst = PyRef::new(py, DunderDictSupport {}).unwrap();
+    py_run!(
+        py,
+        inst,
+        r#"
+        inst.a = 1
+        assert inst.__dict__ == {'a': 1}
+    "#
+    );
+}
+
 #[pyclass(weakref, dict)]
 struct WeakRefDunderDictSupport {}