Merge pull request #446 from RustPython/none_str

windelbouwman · web-flow · commit a75eea56ab89 · 2019-02-12T17:00:46.000+01:00
Add __repr__ and __new__ to NoneType.
diff --git a/tests/snippets/none.py b/tests/snippets/none.py
@@ -14,3 +14,7 @@ def none2():
 assert none() is x
 
 assert none() is none2()
+
+assert str(None) == 'None'
+assert repr(None) == 'None'
+assert type(None)() is None
diff --git a/vm/src/obj/mod.rs b/vm/src/obj/mod.rs
@@ -17,6 +17,7 @@ pub mod objiter;
 pub mod objlist;
 pub mod objmap;
 pub mod objmemory;
+pub mod objnone;
 pub mod objobject;
 pub mod objproperty;
 pub mod objrange;
diff --git a/vm/src/obj/objnone.rs b/vm/src/obj/objnone.rs
@@ -0,0 +1,23 @@
+use super::super::pyobject::{PyContext, PyFuncArgs, PyObjectRef, PyResult, TypeProtocol};
+use super::super::vm::VirtualMachine;
+use super::objtype;
+
+pub fn init(context: &PyContext) {
+    let none_type = &context.none.typ();
+    context.set_attr(&none_type, "__new__", context.new_rustfunc(none_new));
+    context.set_attr(&none_type, "__repr__", context.new_rustfunc(none_repr));
+}
+
+fn none_new(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
+    arg_check!(
+        vm,
+        args,
+        required = [(_zelf, Some(vm.ctx.type_type.clone()))]
+    );
+    Ok(vm.get_none())
+}
+
+fn none_repr(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
+    arg_check!(vm, args, required = [(_zelf, Some(vm.ctx.none().typ()))]);
+    Ok(vm.ctx.new_str("None".to_string()))
+}
diff --git a/vm/src/pyobject.rs b/vm/src/pyobject.rs
@@ -18,6 +18,7 @@ use super::obj::objiter;
 use super::obj::objlist;
 use super::obj::objmap;
 use super::obj::objmemory;
+use super::obj::objnone;
 use super::obj::objobject;
 use super::obj::objproperty;
 use super::obj::objrange;
@@ -318,6 +319,7 @@ impl PyContext {
         objbool::init(&context);
         objcode::init(&context);
         objframe::init(&context);
+        objnone::init(&context);
         exceptions::init(&context);
         context
     }
