Implement Number protocol for PyNone (#3880)

hy-kiera · web-flow · commit 10327b553d6a · 2022-07-16T16:08:54.000+09:00
diff --git a/vm/src/builtins/singletons.rs b/vm/src/builtins/singletons.rs
@@ -1,7 +1,10 @@
 use super::{PyType, PyTypeRef};
 use crate::{
-    class::PyClassImpl, convert::ToPyObject, types::Constructor, Context, Py, PyObjectRef,
-    PyPayload, PyResult, VirtualMachine,
+    class::PyClassImpl,
+    convert::ToPyObject,
+    protocol::PyNumberMethods,
+    types::{AsNumber, Constructor},
+    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "NoneType")]
@@ -39,7 +42,7 @@ impl Constructor for PyNone {
     }
 }
 
-#[pyimpl(with(Constructor))]
+#[pyimpl(with(Constructor, AsNumber))]
 impl PyNone {
     #[pymethod(magic)]
     fn repr(&self) -> String {
@@ -52,6 +55,13 @@ impl PyNone {
     }
 }
 
+impl AsNumber for PyNone {
+    const AS_NUMBER: PyNumberMethods = PyNumberMethods {
+        boolean: Some(|_number, _vm| Ok(false)),
+        ..PyNumberMethods::NOT_IMPLEMENTED
+    };
+}
+
 #[pyclass(module = false, name = "NotImplementedType")]
 #[derive(Debug)]
 pub struct PyNotImplemented;
