bpo-43224: Implement PEP 646 grammar changes (GH-31018)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

1 files changed, 143 insertions, 0 deletions

diff --git a/Lib/test/test_syntax.py b/Lib/test/test_syntax.py
index 5f16a15..3e79ebf 100644
--- a/Lib/test/test_syntax.py
+++ b/Lib/test/test_syntax.py
@@ -1622,6 +1622,149 @@ Corner-cases that used to crash:
     ...     ...
     Traceback (most recent call last):
     SyntaxError: positional patterns follow keyword patterns
+
+Uses of the star operator which should fail:
+
+A[:*b]
+
+    >>> A[:*b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[:(*b)]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: cannot use starred expression here
+    >>> A[:*b] = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> del A[:*b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[*b:]
+
+    >>> A[*b:]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[(*b):]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: cannot use starred expression here
+    >>> A[*b:] = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> del A[*b:]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[*b:*b]
+
+    >>> A[*b:*b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[(*b:*b)]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[*b:*b] = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> del A[*b:*b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[*(1:2)]
+
+    >>> A[*(1:2)]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[*(1:2)] = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> del A[*(1:2)]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[*:] and A[:*]
+
+    >>> A[*:]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[:*]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[*]
+
+    >>> A[*]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[**]
+
+    >>> A[**]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+A[**b]
+
+    >>> A[**b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> A[**b] = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> del A[**b]
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+def f(x: *b)
+
+    >>> def f6(x: *b): pass
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> def f7(x: *b = 1): pass
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+**kwargs: *a
+
+    >>> def f8(**kwargs: *a): pass
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+
+x: *b
+
+    >>> x: *b
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
+    >>> x: *b = 1
+    Traceback (most recent call last):
+        ...
+    SyntaxError: invalid syntax
 """
 
 import re