From 870f1bb5229200b47fa76431630330e5bb51c1e8 Mon Sep 17 00:00:00 2001
From: Jeong YunWon <jeong@youknowone.org>
Date: Thu, 25 Apr 2024 01:10:17 +0900
Subject: [PATCH 1/2] popblock debug

---
 vm/src/frame.rs | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/vm/src/frame.rs b/vm/src/frame.rs
index d62e538051..ff5e2d723d 100644
--- a/vm/src/frame.rs
+++ b/vm/src/frame.rs
@@ -1911,8 +1911,18 @@ impl ExecutingFrame<'_> {
         });
     }
 
+    #[track_caller]
     fn pop_block(&mut self) -> Block {
         let block = self.state.blocks.pop().expect("No more blocks to pop!");
+        #[cfg(debug_assertions)]
+        if self.state.stack.len() < block.level {
+            dbg!(&self);
+            panic!(
+                "stack size reversion: current size({}) < truncates target({}).",
+                self.state.stack.len(),
+                block.level
+            );
+        }
         self.state.stack.truncate(block.level);
         block
     }
@@ -1945,7 +1955,7 @@ impl ExecutingFrame<'_> {
     }
 
     #[inline]
-    #[track_caller] // not a real track_caller but pop_value is not very useful
+    #[track_caller] // not a real track_caller but top_value is not very useful
     fn top_value(&self) -> &PyObject {
         match &*self.state.stack {
             [.., last] => last,

From 8b1b1e4a27c5148f817351b25c466251999891e6 Mon Sep 17 00:00:00 2001
From: Jeong YunWon <jeong@youknowone.org>
Date: Thu, 25 Apr 2024 14:46:44 +0900
Subject: [PATCH 2/2] Fix with __exit__ error handling

---
 vm/src/frame.rs | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/vm/src/frame.rs b/vm/src/frame.rs
index ff5e2d723d..80f848fc94 100644
--- a/vm/src/frame.rs
+++ b/vm/src/frame.rs
@@ -925,7 +925,7 @@ impl ExecutingFrame<'_> {
                     _ => None,
                 };
 
-                let exit = self.pop_value();
+                let exit = self.top_value();
 
                 let args = if let Some(exc) = exc {
                     vm.split_exception(exc)
@@ -933,7 +933,7 @@ impl ExecutingFrame<'_> {
                     (vm.ctx.none(), vm.ctx.none(), vm.ctx.none())
                 };
                 let exit_res = exit.call(args, vm)?;
-                self.push_value(exit_res);
+                self.replace_top(exit_res);
 
                 Ok(None)
             }
@@ -994,7 +994,7 @@ impl ExecutingFrame<'_> {
             }
             bytecode::Instruction::GetANext => {
                 let aiter = self.top_value();
-                let awaitable = vm.call_special_method(&aiter, identifier!(vm, __anext__), ())?;
+                let awaitable = vm.call_special_method(aiter, identifier!(vm, __anext__), ())?;
                 let awaitable = if awaitable.payload_is::<PyCoroutine>() {
                     awaitable
                 } else {
@@ -1954,6 +1954,13 @@ impl ExecutingFrame<'_> {
         self.state.stack.drain(stack_len - count..)
     }
 
+    #[inline]
+    fn replace_top(&mut self, mut top: PyObjectRef) -> PyObjectRef {
+        let last = self.state.stack.last_mut().unwrap();
+        std::mem::swap(&mut top, last);
+        top
+    }
+
     #[inline]
     #[track_caller] // not a real track_caller but top_value is not very useful
     fn top_value(&self) -> &PyObject {