RustPython · youknowone · Dec 26, 2025 · Dec 25, 2025 · Dec 25, 2025 · Dec 25, 2025
diff --git a/.cspell.dict/python-more.txt b/.cspell.dict/python-more.txt
@@ -199,6 +199,7 @@ readbuffer
 reconstructor
 refcnt
 releaselevel
+reraised
 reverseitemiterator
 reverseiterator
 reversekeyiterator

diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py
@@ -1536,8 +1536,6 @@ def test_try_except_as(self):
             """
         self.check_stack_size(snippet)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_try_except_star_qualified(self):
         snippet = """
             try:
@@ -1549,8 +1547,6 @@ def test_try_except_star_qualified(self):
             """
         self.check_stack_size(snippet)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_try_except_star_as(self):
         snippet = """
             try:
@@ -1562,8 +1558,6 @@ def test_try_except_star_as(self):
             """
         self.check_stack_size(snippet)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_try_except_star_finally(self):
         snippet = """
                 try:

diff --git a/crates/codegen/src/compile.rs b/crates/codegen/src/compile.rs
@@ -1510,7 +1510,7 @@ impl Compiler {
                 ..
             }) => {
                 if *is_star {
-                    self.compile_try_star_statement(body, handlers, orelse, finalbody)?
+                    self.compile_try_star_except(body, handlers, orelse, finalbody)?
                 } else {
                     self.compile_try_statement(body, handlers, orelse, finalbody)?
                 }
@@ -2119,14 +2119,157 @@ impl Compiler {
         Ok(())
     }
 
-    fn compile_try_star_statement(
+    fn compile_try_star_except(
         &mut self,
-        _body: &[Stmt],
-        _handlers: &[ExceptHandler],
-        _orelse: &[Stmt],
-        _finalbody: &[Stmt],
+        body: &[Stmt],
+        handlers: &[ExceptHandler],
+        orelse: &[Stmt],
+        finalbody: &[Stmt],
     ) -> CompileResult<()> {
-        Err(self.error(CodegenErrorType::NotImplementedYet))
+        // Simplified except* implementation using CheckEgMatch
+        let handler_block = self.new_block();
+        let finally_block = self.new_block();
+
+        if !finalbody.is_empty() {
+            emit!(
+                self,
+                Instruction::SetupFinally {
+                    handler: finally_block,
+                }
+            );
+        }
+
+        let else_block = self.new_block();
+
+        emit!(
+            self,
+            Instruction::SetupExcept {
+                handler: handler_block,
+            }
+        );
+        self.compile_statements(body)?;
+        emit!(self, Instruction::PopBlock);
+        emit!(self, Instruction::Jump { target: else_block });
+
+        self.switch_to_block(handler_block);
+        // Stack: [exc]
+
+        for handler in handlers {
+            let ExceptHandler::ExceptHandler(ExceptHandlerExceptHandler {
+                type_, name, body, ..
+            }) = handler;
+
+            let skip_block = self.new_block();
+            let next_block = self.new_block();
+
+            // Compile exception type
+            if let Some(exc_type) = type_ {
+                // Check for unparenthesized tuple (e.g., `except* A, B:` instead of `except* (A, B):`)
+                if let Expr::Tuple(ExprTuple { elts, range, .. }) = exc_type.as_ref()
+                    && let Some(first) = elts.first()
+                    && range.start().to_u32() == first.range().start().to_u32()
+                {
+                    return Err(self.error(CodegenErrorType::SyntaxError(
+                        "multiple exception types must be parenthesized".to_owned(),
+                    )));
+                }
+                self.compile_expression(exc_type)?;
+            } else {
+                return Err(self.error(CodegenErrorType::SyntaxError(
+                    "except* must specify an exception type".to_owned(),
+                )));
+            }
+            // Stack: [exc, type]
+
+            emit!(self, Instruction::CheckEgMatch);
+            // Stack: [rest, match]
+
+            // Check if match is None (truthy check)
+            emit!(self, Instruction::CopyItem { index: 1 });
+            emit!(self, Instruction::ToBool);
+            emit!(self, Instruction::PopJumpIfFalse { target: skip_block });
+
+            // Handler matched - store match to name if provided
+            // Stack: [rest, match]
+            if let Some(alias) = name {
+                self.store_name(alias.as_str())?;
+            } else {
+                emit!(self, Instruction::PopTop);
+            }
+            // Stack: [rest]
+
+            self.compile_statements(body)?;
+
+            if let Some(alias) = name {
+                self.emit_load_const(ConstantData::None);
+                self.store_name(alias.as_str())?;
+                self.compile_name(alias.as_str(), NameUsage::Delete)?;
+            }
+
+            emit!(self, Instruction::Jump { target: next_block });
+
+            // No match - pop match (None) and continue with rest
+            self.switch_to_block(skip_block);
+            emit!(self, Instruction::PopTop); // drop match (None)
+            // Stack: [rest]
+
+            self.switch_to_block(next_block);
+            // Stack: [rest] - continue with rest for next handler
+        }
+
+        let handled_block = self.new_block();
+
+        // Check if remainder is truthy (has unhandled exceptions)
+        // Stack: [rest]
+        emit!(self, Instruction::CopyItem { index: 1 });
+        emit!(self, Instruction::ToBool);
+        emit!(
+            self,
+            Instruction::PopJumpIfFalse {
+                target: handled_block
+            }
+        );
+        // Reraise unhandled exceptions
+        emit!(
+            self,
+            Instruction::Raise {
+                kind: bytecode::RaiseKind::Raise
+            }
+        );
+
+        // All exceptions handled
+        self.switch_to_block(handled_block);
+        emit!(self, Instruction::PopTop); // drop remainder (None)
+        emit!(self, Instruction::PopException);
+
+        if !finalbody.is_empty() {
+            emit!(self, Instruction::PopBlock);
+            emit!(self, Instruction::EnterFinally);
+        }
+
+        emit!(
+            self,
+            Instruction::Jump {
+                target: finally_block,
+            }
+        );
+
+        // try-else path
+        self.switch_to_block(else_block);
+        self.compile_statements(orelse)?;
+
+        if !finalbody.is_empty() {
+            emit!(self, Instruction::PopBlock);
+            emit!(self, Instruction::EnterFinally);
+        }
+
+        self.switch_to_block(finally_block);
+        if !finalbody.is_empty() {
+            self.compile_statements(finalbody)?;
+            emit!(self, Instruction::EndFinally);
+        }
+
+        Ok(())
     }
 
     fn is_forbidden_arg_name(name: &str) -> bool {

diff --git a/crates/compiler-core/src/bytecode.rs b/crates/compiler-core/src/bytecode.rs
@@ -574,7 +574,7 @@ op_arg_enum!(
     #[derive(Copy, Clone, Debug, PartialEq, Eq)]
     #[repr(u8)]
     pub enum IntrinsicFunction2 {
-        // PrepReraiseS tar = 1,
+        PrepReraiseStar = 1,
         TypeVarWithBound = 2,
         TypeVarWithConstraint = 3,
         SetFunctionTypeParams = 4,
@@ -652,6 +652,9 @@ pub enum Instruction {
     CallMethodPositional {
         nargs: Arg<u32>,
     },
+    /// Check if exception matches except* handler type.
+    /// Pops exc_value and match_type, pushes (rest, match).
+    CheckEgMatch,
     CompareOperation {
         op: Arg<ComparisonOperator>,
     },
@@ -1721,6 +1724,7 @@ impl Instruction {
             CallMethodKeyword { nargs } => -1 - (nargs.get(arg) as i32) - 3 + 1,
             CallFunctionEx { has_kwargs } => -1 - (has_kwargs.get(arg) as i32) - 1 + 1,
             CallMethodEx { has_kwargs } => -1 - (has_kwargs.get(arg) as i32) - 3 + 1,
+            CheckEgMatch => 0, // pops 2 (exc, type), pushes 2 (rest, match)
             ConvertValue { .. } => 0,
             FormatSimple => 0,
             FormatWithSpec => -1,
@@ -1887,6 +1891,7 @@ impl Instruction {
             CallMethodEx { has_kwargs } => w!(CALL_METHOD_EX, has_kwargs),
             CallMethodKeyword { nargs } => w!(CALL_METHOD_KEYWORD, nargs),
             CallMethodPositional { nargs } => w!(CALL_METHOD_POSITIONAL, nargs),
+            CheckEgMatch => w!(CHECK_EG_MATCH),
             CompareOperation { op } => w!(COMPARE_OPERATION, ?op),
             ContainsOp(inv) => w!(CONTAINS_OP, ?inv),
             Continue { target } => w!(CONTINUE, target),

diff --git a/crates/vm/src/exceptions.rs b/crates/vm/src/exceptions.rs
@@ -2432,3 +2432,127 @@ pub(super) mod types {
     #[repr(transparent)]
     pub struct PyEncodingWarning(PyWarning);
 }
+
+/// Match exception against except* handler type.
+/// Returns (rest, match) tuple.
+pub fn exception_group_match(
+    exc_value: &PyObjectRef,
+    match_type: &PyObjectRef,
+    vm: &VirtualMachine,
+) -> PyResult<(PyObjectRef, PyObjectRef)> {
+    // Implements _PyEval_ExceptionGroupMatch
+
+    // If exc_value is None, return (None, None)
+    if vm.is_none(exc_value) {
+        return Ok((vm.ctx.none(), vm.ctx.none()));
+    }
+
+    // Check if exc_value matches match_type
+    if exc_value.is_instance(match_type, vm)? {
+        // Full match of exc itself
+        let is_eg = exc_value.fast_isinstance(vm.ctx.exceptions.base_exception_group);
+        let matched = if is_eg {
+            exc_value.clone()
+        } else {
+            // Naked exception - wrap it in ExceptionGroup
+            let excs = vm.ctx.new_tuple(vec![exc_value.clone()]);
+            let eg_type: PyObjectRef = crate::exception_group::exception_group().to_owned().into();
+            let wrapped = eg_type.call((vm.ctx.new_str(""), excs), vm)?;
+            // Copy traceback from original exception
+            if let Ok(exc) = exc_value.clone().downcast::<types::PyBaseException>()
+                && let Some(tb) = exc.__traceback__()
+                && let Ok(wrapped_exc) = wrapped.clone().downcast::<types::PyBaseException>()
+            {
+                let _ = wrapped_exc.set___traceback__(tb.into(), vm);
+            }
+            wrapped
+        };
+        return Ok((vm.ctx.none(), matched));
+    }
+
+    // Check for partial match if it's an exception group
+    if exc_value.fast_isinstance(vm.ctx.exceptions.base_exception_group) {
+        let pair = vm.call_method(exc_value, "split", (match_type.clone(),))?;
+        let pair_tuple: PyTupleRef = pair.try_into_value(vm)?;
+        if pair_tuple.len() < 2 {
+            return Err(vm.new_type_error(format!(
+                "{}.split must return a 2-tuple, got tuple of size {}",
+                exc_value.class().name(),
+                pair_tuple.len()
+            )));
+        }
+        let matched = pair_tuple[0].clone();
+        let rest = pair_tuple[1].clone();
+        return Ok((rest, matched));
+    }
+
+    // No match
+    Ok((exc_value.clone(), vm.ctx.none()))
+}
+
+/// Prepare exception for reraise in except* block.
+pub fn prep_reraise_star(orig: PyObjectRef, excs: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+    // Implements _PyExc_PrepReraiseStar
+    use crate::builtins::PyList;
+
+    let excs_list = excs
+        .downcast::<PyList>()
+        .map_err(|_| vm.new_type_error("expected list for prep_reraise_star"))?;
+
+    let excs_vec: Vec<PyObjectRef> = excs_list.borrow_vec().to_vec();
+
+    // Filter out None values
+    let mut raised: Vec<PyObjectRef> = Vec::new();
+    let mut reraised: Vec<PyObjectRef> = Vec::new();
+
+    for exc in excs_vec {
+        if vm.is_none(&exc) {
+            continue;
+        }
+        // Check if this exception was in the original exception group
+        if !vm.is_none(&orig) && is_same_exception_metadata(&exc, &orig, vm) {
+            reraised.push(exc);
+        } else {
+            raised.push(exc);
+        }
+    }
+
+    // If no exceptions to reraise, return None
+    if raised.is_empty() && reraised.is_empty() {
+        return Ok(vm.ctx.none());
+    }
+
+    // Combine raised and reraised exceptions
+    let mut all_excs = raised;
+    all_excs.extend(reraised);
+
+    if all_excs.len() == 1 {
+        // If only one exception, just return it
+        return Ok(all_excs.into_iter().next().unwrap());
+    }
+
+    // Create new ExceptionGroup
+    let excs_tuple = vm.ctx.new_tuple(all_excs);
+    let eg_type: PyObjectRef = crate::exception_group::exception_group().to_owned().into();
+    eg_type.call((vm.ctx.new_str(""), excs_tuple), vm)
+}
+
+/// Check if two exceptions have the same metadata (for reraise detection)
+fn is_same_exception_metadata(exc1: &PyObjectRef, exc2: &PyObjectRef, vm: &VirtualMachine) -> bool {
+    // Check if exc1 is part of exc2's exception group
+    if exc2.fast_isinstance(vm.ctx.exceptions.base_exception_group) {
+        let exc_class: PyObjectRef = exc1.class().to_owned().into();
+        if let Ok(result) = vm.call_method(exc2, "subgroup", (exc_class,))
+            && !vm.is_none(&result)
+            && let Ok(subgroup_excs) = result.get_attr("exceptions", vm)
+            && let Ok(tuple) = subgroup_excs.downcast::<PyTuple>()
+        {
+            for e in tuple.iter() {
+                if e.is(exc1) {
+                    return true;
+                }
+            }
+        }
+    }
+    exc1.is(exc2)
+}
diff --git a/crates/vm/src/frame.rs b/crates/vm/src/frame.rs
@@ -691,6 +691,15 @@ impl ExecutingFrame<'_> {
                 let args = self.collect_positional_args(nargs.get(arg));
                 self.execute_method_call(args, vm)
             }
+            bytecode::Instruction::CheckEgMatch => {
+                let match_type = self.pop_value();
+                let exc_value = self.pop_value();
+                let (rest, matched) =
+                    crate::exceptions::exception_group_match(&exc_value, &match_type, vm)?;
+                self.push_value(rest);
+                self.push_value(matched);
+                Ok(None)
+            }
             bytecode::Instruction::CompareOperation { op } => self.execute_compare(vm, op.get(arg)),
             bytecode::Instruction::ContainsOp(invert) => {
                 let b = self.pop_value();
@@ -2494,6 +2503,12 @@ impl ExecutingFrame<'_> {
                         .into();
                 Ok(type_var)
             }
+            bytecode::IntrinsicFunction2::PrepReraiseStar => {
+                // arg1 = orig (original exception)
+                // arg2 = excs (list of exceptions raised/reraised in except* blocks)
+                // Returns: exception to reraise, or None if nothing to reraise
+                crate::exceptions::prep_reraise_star(arg1, arg2, vm)
+            }
         }
     }