Exception group stage4 - implement except*

Doc/library/dis.rst

@@ -953,6 +953,10 @@ All of the following opcodes use their arguments.
 
    .. versionadded:: 3.1
 
+.. opcode:: JUMP_IF_NOT_EG_MATCH (target)
+
+   TODO: add doc
+
 .. opcode:: JUMP_IF_NOT_EXC_MATCH (target)
 
    Tests whether the second value on the stack is an exception matching TOS,

Grammar/python.gram

@@ -196,12 +196,17 @@ with_item[withitem_ty]:
     | e=expression { _Py_withitem(e, NULL, p->arena) }
 
 try_stmt[stmt_ty]:
-    | 'try' ':' b=block f=finally_block { _Py_Try(b, NULL, NULL, f, EXTRA) }
-    | 'try' ':' b=block ex[asdl_excepthandler_seq*]=except_block+ el=[else_block] f=[finally_block] { _Py_Try(b, ex, el, f, EXTRA) }
+    | 'try' ':' b=block f=finally_block { _Py_Try(b, NULL, NULL, f, 0, EXTRA) }
+    | 'try' ':' b=block ex[asdl_excepthandler_seq*]=except_block+ el=[else_block] f=[finally_block] { _Py_Try(b, ex, el, f, 0, EXTRA) }
+    | 'try' ':' b=block ex[asdl_excepthandler_seq*]=except_star_block+ el=[else_block] f=[finally_block] { _Py_Try(b, ex, el, f, 1, EXTRA) }
 except_block[excepthandler_ty]:
     | 'except' e=expression t=['as' z=NAME { z }] ':' b=block {
         _Py_ExceptHandler(e, (t) ? ((expr_ty) t)->v.Name.id : NULL, b, EXTRA) }
     | 'except' ':' b=block { _Py_ExceptHandler(NULL, NULL, b, EXTRA) }
+except_star_block[excepthandler_ty]:
+    | 'except' '*' e=expression t=['as' z=NAME { z }] ':' b=block {
+        _Py_ExceptHandler(e, (t) ? ((expr_ty) t)->v.Name.id : NULL, b, EXTRA) }
+    | 'except' '*' ':' b=block { _Py_ExceptHandler(NULL, NULL, b, EXTRA) }
 finally_block[asdl_stmt_seq*]: 'finally' ':' a=block { a }
 
 return_stmt[stmt_ty]:

Include/cpython/pyerrors.h

@@ -24,6 +24,12 @@ typedef struct {
     PyObject *print_file_and_line;
 } PySyntaxErrorObject;
 
+typedef struct {
+    PyException_HEAD
+    PyObject *msg;
+    PyObject *excs;
+} PyExceptionGroupObject;
+
 typedef struct {
     PyException_HEAD
     PyObject *msg;

Include/internal/pycore_ast.h

@@ -209,6 +209,7 @@ struct ast_state {
     PyObject *right;
     PyObject *simple;
     PyObject *slice;
+    PyObject *star;
     PyObject *step;
     PyObject *stmt_type;
     PyObject *tag;

Include/pyerrors.h

@@ -85,6 +85,7 @@ PyAPI_DATA(PyObject *) PyExc_BufferError;
 PyAPI_DATA(PyObject *) PyExc_EOFError;
 PyAPI_DATA(PyObject *) PyExc_FloatingPointError;
 PyAPI_DATA(PyObject *) PyExc_OSError;
+PyAPI_DATA(PyObject *) PyExc_ExceptionGroup;
 PyAPI_DATA(PyObject *) PyExc_ImportError;
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03060000
 PyAPI_DATA(PyObject *) PyExc_ModuleNotFoundError;

Include/traceback.h

@@ -9,6 +9,9 @@ extern "C" {
 PyAPI_FUNC(int) PyTraceBack_Here(PyFrameObject *);
 PyAPI_FUNC(int) PyTraceBack_Print(PyObject *, PyObject *);
 
+int PyTraceBack_Print_Indented(PyObject *, PyObject *, int);
+int _Py_WriteIndent(int, PyObject *);
+
 /* Reveal traceback type so we can typecheck traceback objects */
 PyAPI_DATA(PyTypeObject) PyTraceBack_Type;
 #define PyTraceBack_Check(v) Py_IS_TYPE(v, &PyTraceBack_Type)

Lib/importlib/_bootstrap_external.py

@@ -321,7 +321,7 @@ def _write_atomic(path, data, mode=0o666):
 # Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
 # in PC/launcher.c must also be updated.
 
-MAGIC_NUMBER = (3432).to_bytes(2, 'little') + b'\r\n'
+MAGIC_NUMBER = (3433).to_bytes(2, 'little') + b'\r\n'
 _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 
 _PYCACHE = '__pycache__'

Lib/opcode.py

@@ -162,6 +162,7 @@ def jabs_op(name, op):
 def_op('IS_OP', 117)
 def_op('CONTAINS_OP', 118)
 
+jabs_op('JUMP_IF_NOT_EG_MATCH', 120)
 jabs_op('JUMP_IF_NOT_EXC_MATCH', 121)
 jrel_op('SETUP_FINALLY', 122)   # Distance to target address
 

Lib/test/exception_hierarchy.txt

@@ -2,6 +2,7 @@ BaseException
  +-- SystemExit
  +-- KeyboardInterrupt
  +-- GeneratorExit
+ +-- ExceptionGroup
  +-- Exception
       +-- StopIteration
       +-- StopAsyncIteration