From 4fad83e3cc23456c952356a321394d377c353f69 Mon Sep 17 00:00:00 2001
From: jfh <jfh@imijmi.eu>
Date: Wed, 13 Oct 2021 19:32:31 +0300
Subject: [PATCH] Fix recursions in isinstance and issubclass.

---
 Lib/test/test_isinstance.py |  4 ----
 vm/src/vm.rs                | 13 ++++++++-----
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/Lib/test/test_isinstance.py b/Lib/test/test_isinstance.py
index f8e025c9f1..104f519f56 100644
--- a/Lib/test/test_isinstance.py
+++ b/Lib/test/test_isinstance.py
@@ -241,15 +241,11 @@ class TestIsInstanceIsSubclass(unittest.TestCase):
         self.assertEqual(True, issubclass(int, (int, (float, int))))
         self.assertEqual(True, issubclass(str, (str, (Child, str))))
 
-    # TODO: RUSTPYTHON requires issue 2680 for stack depth detection in Rust
-    @unittest.expectedFailure
     def test_subclass_recursion_limit(self):
         # make sure that issubclass raises RecursionError before the C stack is
         # blown
         self.assertRaises(RecursionError, blowstack, issubclass, str, str)
 
-    # TODO: RUSTPYTHON requires issue 2680 for stack depth detection in Rust
-    @unittest.expectedFailure
     def test_isinstance_recursion_limit(self):
         # make sure that issubclass raises RecursionError before the C stack is
         # blown
diff --git a/vm/src/vm.rs b/vm/src/vm.rs
index 3997d9f3c1..1032dff343 100644
--- a/vm/src/vm.rs
+++ b/vm/src/vm.rs
@@ -902,7 +902,7 @@ impl VirtualMachine {
     }
 
     pub fn to_repr(&self, obj: &PyObjectRef) -> PyResult<PyStrRef> {
-        self.with_recursion(" while getting the repr of an object", || {
+        self.with_recursion("while getting the repr of an object", || {
             let repr = self.call_special_method(obj.clone(), "__repr__", ())?;
             repr.try_into_value(self)
         })
@@ -1057,7 +1057,7 @@ impl VirtualMachine {
 
         if let Ok(tuple) = PyTupleRef::try_from_object(self, cls.clone()) {
             for typ in tuple.as_slice().iter() {
-                if self.isinstance(obj, typ)? {
+                if self.with_recursion("in __instancecheck__", || self.isinstance(obj, typ))? {
                     return Ok(true);
                 }
             }
@@ -1065,7 +1065,8 @@ impl VirtualMachine {
         }
 
         if let Ok(meth) = self.get_special_method(cls.clone(), "__instancecheck__")? {
-            let ret = meth.invoke((obj.clone(),), self)?;
+            let ret =
+                self.with_recursion("in __instancecheck__", || meth.invoke((obj.clone(),), self))?;
             return ret.try_to_bool(self);
         }
 
@@ -1139,7 +1140,7 @@ impl VirtualMachine {
 
         if let Ok(tuple) = PyTupleRef::try_from_object(self, cls.clone()) {
             for typ in tuple.as_slice().iter() {
-                if self.issubclass(subclass, typ)? {
+                if self.with_recursion("in __subclasscheck__", || self.issubclass(subclass, typ))? {
                     return Ok(true);
                 }
             }
@@ -1147,7 +1148,9 @@ impl VirtualMachine {
         }
 
         if let Ok(meth) = self.get_special_method(cls.clone(), "__subclasscheck__")? {
-            let ret = meth.invoke((subclass.clone(),), self)?;
+            let ret = self.with_recursion("in __subclasscheck__", || {
+                meth.invoke((subclass.clone(),), self)
+            })?;
             return ret.try_to_bool(self);
         }