Added edge case for invalid control flow in except block nested inside except* block, other minor fixes

Author: coldwolverine

mypy/semanal.py

@@ -519,21 +519,21 @@ def allow_unbound_tvars_set(self) -> Iterator[None]:
 
     @contextmanager
     def inside_except_star_block_set(
-        self, value: bool, enteringLoop: bool = False
+        self, value: bool, entering_loop: bool = False
     ) -> Iterator[None]:
         old = self.inside_except_star_block
         self.inside_except_star_block = value
 
         # Return statement would still be in except* scope if entering loops
-        if not enteringLoop:
+        if not entering_loop:
             old_return_stmt_flag = self.return_stmt_inside_except_star_block
             self.return_stmt_inside_except_star_block = value
 
         try:
             yield
         finally:
             self.inside_except_star_block = old
-            if not enteringLoop:
+            if not entering_loop:
                 self.return_stmt_inside_except_star_block = old_return_stmt_flag
 
     #
@@ -5290,7 +5290,7 @@ def visit_return_stmt(self, s: ReturnStmt) -> None:
         if not self.is_func_scope():
             self.fail('"return" outside function', s)
         if self.return_stmt_inside_except_star_block:
-            self.fail('"return" not allowed in except* block', s, serious=True, blocker=True)
+            self.fail('"return" not allowed in except* block', s, serious=True)
         if s.expr:
             s.expr.accept(self)
 
@@ -5324,7 +5324,7 @@ def visit_while_stmt(self, s: WhileStmt) -> None:
         self.statement = s
         s.expr.accept(self)
         self.loop_depth[-1] += 1
-        with self.inside_except_star_block_set(value=False, enteringLoop=True):
+        with self.inside_except_star_block_set(value=False, entering_loop=True):
             s.body.accept(self)
         self.loop_depth[-1] -= 1
         self.visit_block_maybe(s.else_body)
@@ -5349,7 +5349,7 @@ def visit_for_stmt(self, s: ForStmt) -> None:
                 s.index_type = analyzed
 
         self.loop_depth[-1] += 1
-        with self.inside_except_star_block_set(value=False, enteringLoop=True):
+        with self.inside_except_star_block_set(value=False, entering_loop=True):
             self.visit_block(s.body)
         self.loop_depth[-1] -= 1
         self.visit_block_maybe(s.else_body)
@@ -5359,14 +5359,14 @@ def visit_break_stmt(self, s: BreakStmt) -> None:
         if self.loop_depth[-1] == 0:
             self.fail('"break" outside loop', s, serious=True, blocker=True)
         if self.inside_except_star_block:
-            self.fail('"break" not allowed in except* block', s, serious=True, blocker=True)
+            self.fail('"break" not allowed in except* block', s, serious=True)
 
     def visit_continue_stmt(self, s: ContinueStmt) -> None:
         self.statement = s
         if self.loop_depth[-1] == 0:
             self.fail('"continue" outside loop', s, serious=True, blocker=True)
         if self.inside_except_star_block:
-            self.fail('"continue" not allowed in except* block', s, serious=True, blocker=True)
+            self.fail('"continue" not allowed in except* block', s, serious=True)
 
     def visit_if_stmt(self, s: IfStmt) -> None:
         self.statement = s
@@ -5387,7 +5387,7 @@ def analyze_try_stmt(self, s: TryStmt, visitor: NodeVisitor[None]) -> None:
                 type.accept(visitor)
             if var:
                 self.analyze_lvalue(var)
-            with self.inside_except_star_block_set(s.is_star):
+            with self.inside_except_star_block_set(self.inside_except_star_block or s.is_star):
                 handler.accept(visitor)
         if s.else_body:
             s.else_body.accept(visitor)

test-data/unit/check-python311.test

@@ -196,9 +196,38 @@ def foo():
                 return  # E: "return" not allowed in except* block
 [builtins fixtures/exception.pyi]
 
+[case testContinueInExceptBlockNestedInExceptStarBlock]
+# flags: --python-version 3.11
+while True:
+    try:
+        ...
+    except* Exception:
+        try:
+            ...
+        except Exception:
+            continue  # E: "continue" not allowed in except* block
+        continue  # E: "continue" not allowed in except* block
+[builtins fixtures/exception.pyi]
+
+[case testReturnInExceptBlockNestedInExceptStarBlock]
+# flags: --python-version 3.11
+def foo():
+    try:
+        ...
+    except* Exception:
+        try:
+            ...
+        except Exception:
+            return  # E: "return" not allowed in except* block
+        return  # E: "return" not allowed in except* block
+[builtins fixtures/exception.pyi]
+
 [case testBreakContinueReturnInExceptStarBlock1]
 # flags: --python-version 3.11
-class range: pass
+from typing import Sequence
+class range(Sequence[int]): 
+    def __init__(self, __x: int, __y: int = ..., __z: int = ...) -> None: pass
+
 def foo() -> None:
     for _ in range(5):
         try: