Visitar URL original
bpo-41816: `StrEnum.__str__` is `str.__str__` by ethanfurman · Pull Request #22362 · python/cpython · GitHub
Skip to content

bpo-41816: StrEnum.__str__ is str.__str__ #22362

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ethanfurman merged 3 commits into from
Sep 22, 2020
Merged

bpo-41816: StrEnum.__str__ is str.__str__ #22362

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
e38abfb
StrEnum.__str__ is str.__str__
ethanfurman Sep 22, 2020
b2e6923
add format test
ethanfurman Sep 22, 2020
4a4867c
add another test
ethanfurman Sep 22, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 15 additions & 0 deletions Doc/library/enum.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -622,6 +622,11 @@ an incorrect member::
Before :class:`StrEnum`, ``Directions.NORTH`` would have been the :class:`tuple`
``('north',)``.

.. note::

Unlike other Enum's, ``str(StrEnum.member)`` will return the value of the
member instead of the usual ``"EnumClass.member"``.

.. versionadded:: 3.10


Expand Down Expand Up @@ -1217,3 +1222,13 @@ all named flags and all named combinations of flags that are in the value::
>>> Color(7) # not named combination
<Color.CYAN|MAGENTA|BLUE|YELLOW|GREEN|RED: 7>

``StrEnum`` and :meth:`str.__str__`
"""""""""""""""""""""""""""""""""""

An important difference between :class:`StrEnum` and other Enums is the
:meth:`__str__` method; because :class:`StrEnum` members are strings, some
parts of Python will read the string data directly, while others will call
:meth:`str()`. To make those two operations have the same result,
:meth:`StrEnum.__str__` will be the same as :meth:`str.__str__` so that
``str(StrEnum.member) == StrEnum.member`` is true.

2 changes: 2 additions & 0 deletions Lib/enum.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -718,6 +718,8 @@ def __new__(cls, *values):
member._value_ = value
return member

__str__ = str.__str__


def _reduce_ex_by_name(self, proto):
return self.name
Expand Down
31 changes: 31 additions & 0 deletions Lib/test/test_enum.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2036,6 +2036,37 @@ class GoodStrEnum(StrEnum):
two = '2'
three = b'3', 'ascii'
Comment thread
ethanfurman marked this conversation as resolved.
four = b'4', 'latin1', 'strict'
self.assertEqual(GoodStrEnum.one, '1')
self.assertEqual(str(GoodStrEnum.one), '1')
self.assertEqual(GoodStrEnum.one, str(GoodStrEnum.one))
Comment thread
ethanfurman marked this conversation as resolved.
self.assertEqual(GoodStrEnum.one, '{}'.format(GoodStrEnum.one))
#
class DumbMixin:
def __str__(self):
return "don't do this"
class DumbStrEnum(DumbMixin, StrEnum):
five = '5'
six = '6'
seven = '7'
self.assertEqual(DumbStrEnum.seven, '7')
self.assertEqual(str(DumbStrEnum.seven), "don't do this")
#
class EnumMixin(Enum):
def hello(self):
print('hello from %s' % (self, ))
class HelloEnum(EnumMixin, StrEnum):
eight = '8'
self.assertEqual(HelloEnum.eight, '8')
self.assertEqual(HelloEnum.eight, str(HelloEnum.eight))
#
class GoodbyeMixin:
def goodbye(self):
print('%s wishes you a fond farewell')
class GoodbyeEnum(GoodbyeMixin, EnumMixin, StrEnum):
nine = '9'
self.assertEqual(GoodbyeEnum.nine, '9')
self.assertEqual(GoodbyeEnum.nine, str(GoodbyeEnum.nine))
#
with self.assertRaisesRegex(TypeError, '1 is not a string'):
class FirstFailedStrEnum(StrEnum):
one = 1
Expand Down