Fix define_exception! of PyStopIteration to set value of value attribute

Co-authored-by: NanHee Kim <kimnanhee0225@gmail.com>

Author: tgsong827

Lib/test/test_yield_from.py

@@ -338,8 +338,6 @@ def g2():
             "Finishing g1",
         ])
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_value_attribute_of_StopIteration_exception(self):
         """
         Test 'value' attribute of StopIteration exception

vm/src/exceptions.rs

@@ -712,7 +712,7 @@ impl ExceptionZoo {
         extend_exception!(PyException, ctx, excs.exception_type);
 
         extend_exception!(PyStopIteration, ctx, excs.stop_iteration, {
-            "value" => ctx.new_readonly_getset("value", excs.stop_iteration, make_arg_getter(0)),
+            "value" => ctx.none(),
         });
         extend_exception!(PyStopAsyncIteration, ctx, excs.stop_async_iteration);
 
@@ -1098,8 +1098,15 @@ pub(super) mod types {
         PyStopIteration,
         PyException,
         stop_iteration,
-        "Signal the end from iterator.__next__()."
+        "Signal the end from iterator.__next__().",
+        base_exception_new,
+        stop_iteration_init
+    }
+    fn stop_iteration_init(zelf: PyObjectRef, args: FuncArgs, vm: &VirtualMachine) -> PyResult<()> {
+        zelf.set_attr("value", vm.unwrap_or_none(args.args.get(0).cloned()), vm)?;
+        Ok(())
     }
+
     define_exception! {
         PyStopAsyncIteration,
         PyException,

vm/src/vm/vm_new.rs

@@ -270,7 +270,9 @@ impl VirtualMachine {
         } else {
             Vec::new()
         };
-        self.new_exception(self.ctx.exceptions.stop_iteration.to_owned(), args)
+        let exc = self.new_exception(self.ctx.exceptions.stop_iteration.to_owned(), args.clone());
+        // To initialize the `value` attribute to first argument
+        self.set_exception_attr(exc, "value", args.get(0).cloned())
     }
 
     fn new_downcast_error(
@@ -312,4 +314,19 @@ impl VirtualMachine {
             obj.as_object(),
         )
     }
+
+    fn set_exception_attr(
+        &self,
+        exc: PyBaseExceptionRef,
+        attr_name: &str,
+        attr_value: Option<PyObjectRef>,
+    ) -> PyBaseExceptionRef {
+        match exc
+            .as_object()
+            .set_attr(attr_name, self.unwrap_or_none(attr_value), self)
+        {
+            Ok(_) => exc,
+            Err(e) => e,
+        }
+    }
 }