diff --git a/Lib/csv.py b/Lib/csv.py index bb3ee269ae7931..05899d2daca590 100644 --- a/Lib/csv.py +++ b/Lib/csv.py @@ -4,6 +4,7 @@ """ import re +import types from _csv import Error, __version__, writer, reader, register_dialect, \ unregister_dialect, get_dialect, list_dialects, \ field_size_limit, \ @@ -126,6 +127,8 @@ def __next__(self): d[key] = self.restval return d + __class_getitem__ = classmethod(types.GenericAlias) + class DictWriter: def __init__(self, f, fieldnames, restval="", extrasaction="raise", @@ -156,6 +159,8 @@ def writerow(self, rowdict): def writerows(self, rowdicts): return self.writer.writerows(map(self._dict_to_list, rowdicts)) + __class_getitem__ = classmethod(types.GenericAlias) + # Guard Sniffer's type checking against builds that exclude complex() try: complex diff --git a/Lib/test/test_genericalias.py b/Lib/test/test_genericalias.py index 6959c2ae3c80e3..1afb7ea4f85d0e 100644 --- a/Lib/test/test_genericalias.py +++ b/Lib/test/test_genericalias.py @@ -11,6 +11,7 @@ from concurrent.futures.thread import _WorkItem from contextlib import AbstractContextManager, AbstractAsyncContextManager from contextvars import ContextVar, Token +from csv import DictReader, DictWriter from dataclasses import Field from functools import partial, partialmethod, cached_property from graphlib import TopologicalSorter @@ -122,7 +123,8 @@ class BaseTest(unittest.TestCase): WeakSet, ReferenceType, ref, ShareableList, Future, _WorkItem, - Morsel] + Morsel, + DictReader, DictWriter] if ctypes is not None: generic_types.extend((ctypes.Array, ctypes.LibraryLoader)) if ValueProxy is not None: diff --git a/Misc/ACKS b/Misc/ACKS index a55706d508a41d..f3d8924ea62af5 100644 --- a/Misc/ACKS +++ b/Misc/ACKS @@ -1228,6 +1228,7 @@ Alessandro Moura Pablo Mouzo Mher Movsisyan Ruslan Mstoi +Marc Mueller Valentina Mukhamedzhanova Michael Mulich Sape Mullender diff --git a/Misc/NEWS.d/next/Library/2022-05-06-13-00-57.gh-issue-92391.s-Lase.rst b/Misc/NEWS.d/next/Library/2022-05-06-13-00-57.gh-issue-92391.s-Lase.rst new file mode 100644 index 00000000000000..e042671dae816b --- /dev/null +++ b/Misc/NEWS.d/next/Library/2022-05-06-13-00-57.gh-issue-92391.s-Lase.rst @@ -0,0 +1,3 @@ +Add :meth:`~object.__class_getitem__` to :class:`csv.DictReader` and +:class:`csv.DictWriter`, allowing them to be parameterized at runtime. +Patch by Marc Mueller.