Add AutoEnum: automatically provides next value if missing. Issue 26988.
diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index 564c0e9..4a732f9 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -3,7 +3,7 @@
import pydoc
import unittest
from collections import OrderedDict
-from enum import Enum, IntEnum, EnumMeta, unique
+from enum import EnumMeta, Enum, IntEnum, AutoEnum, unique
from io import StringIO
from pickle import dumps, loads, PicklingError, HIGHEST_PROTOCOL
from test import support
@@ -1570,6 +1570,328 @@
self.assertEqual(LabelledList.unprocessed, 1)
self.assertEqual(LabelledList(1), LabelledList.unprocessed)
+ def test_ignore_as_str(self):
+ from datetime import timedelta
+ class Period(Enum, ignore='Period i'):
+ """
+ different lengths of time
+ """
+ def __new__(cls, value, period):
+ obj = object.__new__(cls)
+ obj._value_ = value
+ obj.period = period
+ return obj
+ Period = vars()
+ for i in range(367):
+ Period['Day%d' % i] = timedelta(days=i), 'day'
+ for i in range(53):
+ Period['Week%d' % i] = timedelta(days=i*7), 'week'
+ for i in range(13):
+ Period['Month%d' % i] = i, 'month'
+ OneDay = Day1
+ OneWeek = Week1
+ self.assertEqual(Period.Day7.value, timedelta(days=7))
+ self.assertEqual(Period.Day7.period, 'day')
+
+ def test_ignore_as_list(self):
+ from datetime import timedelta
+ class Period(Enum, ignore=['Period', 'i']):
+ """
+ different lengths of time
+ """
+ def __new__(cls, value, period):
+ obj = object.__new__(cls)
+ obj._value_ = value
+ obj.period = period
+ return obj
+ Period = vars()
+ for i in range(367):
+ Period['Day%d' % i] = timedelta(days=i), 'day'
+ for i in range(53):
+ Period['Week%d' % i] = timedelta(days=i*7), 'week'
+ for i in range(13):
+ Period['Month%d' % i] = i, 'month'
+ OneDay = Day1
+ OneWeek = Week1
+ self.assertEqual(Period.Day7.value, timedelta(days=7))
+ self.assertEqual(Period.Day7.period, 'day')
+
+ def test_new_with_no_value_and_int_base_class(self):
+ class NoValue(int, Enum):
+ def __new__(cls, value):
+ obj = int.__new__(cls, value)
+ obj.index = len(cls.__members__)
+ return obj
+ this = 1
+ that = 2
+ self.assertEqual(list(NoValue), [NoValue.this, NoValue.that])
+ self.assertEqual(NoValue.this, 1)
+ self.assertEqual(NoValue.this.value, 1)
+ self.assertEqual(NoValue.this.index, 0)
+ self.assertEqual(NoValue.that, 2)
+ self.assertEqual(NoValue.that.value, 2)
+ self.assertEqual(NoValue.that.index, 1)
+
+ def test_new_with_no_value(self):
+ class NoValue(Enum):
+ def __new__(cls, value):
+ obj = object.__new__(cls)
+ obj.index = len(cls.__members__)
+ return obj
+ this = 1
+ that = 2
+ self.assertEqual(list(NoValue), [NoValue.this, NoValue.that])
+ self.assertEqual(NoValue.this.value, 1)
+ self.assertEqual(NoValue.this.index, 0)
+ self.assertEqual(NoValue.that.value, 2)
+ self.assertEqual(NoValue.that.index, 1)
+
+
+class TestAutoNumber(unittest.TestCase):
+
+ def test_autonumbering(self):
+ class Color(AutoEnum):
+ red
+ green
+ blue
+ self.assertEqual(list(Color), [Color.red, Color.green, Color.blue])
+ self.assertEqual(Color.red.value, 1)
+ self.assertEqual(Color.green.value, 2)
+ self.assertEqual(Color.blue.value, 3)
+
+ def test_autointnumbering(self):
+ class Color(int, AutoEnum):
+ red
+ green
+ blue
+ self.assertTrue(isinstance(Color.red, int))
+ self.assertEqual(Color.green, 2)
+ self.assertTrue(Color.blue > Color.red)
+
+ def test_autonumbering_with_start(self):
+ class Color(AutoEnum, start=7):
+ red
+ green
+ blue
+ self.assertEqual(list(Color), [Color.red, Color.green, Color.blue])
+ self.assertEqual(Color.red.value, 7)
+ self.assertEqual(Color.green.value, 8)
+ self.assertEqual(Color.blue.value, 9)
+
+ def test_autonumbering_with_start_and_skip(self):
+ class Color(AutoEnum, start=7):
+ red
+ green
+ blue = 11
+ brown
+ self.assertEqual(list(Color), [Color.red, Color.green, Color.blue, Color.brown])
+ self.assertEqual(Color.red.value, 7)
+ self.assertEqual(Color.green.value, 8)
+ self.assertEqual(Color.blue.value, 11)
+ self.assertEqual(Color.brown.value, 12)
+
+
+ def test_badly_overridden_ignore(self):
+ with self.assertRaisesRegex(TypeError, "'int' object is not callable"):
+ class Color(AutoEnum):
+ _ignore_ = ()
+ red
+ green
+ blue
+ @property
+ def whatever(self):
+ pass
+ with self.assertRaisesRegex(TypeError, "'int' object is not callable"):
+ class Color(AutoEnum, ignore=None):
+ red
+ green
+ blue
+ @property
+ def whatever(self):
+ pass
+ with self.assertRaisesRegex(TypeError, "'int' object is not callable"):
+ class Color(AutoEnum, ignore='classmethod staticmethod'):
+ red
+ green
+ blue
+ @property
+ def whatever(self):
+ pass
+
+ def test_property(self):
+ class Color(AutoEnum):
+ red
+ green
+ blue
+ @property
+ def cap_name(self):
+ return self.name.title()
+ self.assertEqual(Color.blue.cap_name, 'Blue')
+
+ def test_magic_turns_off(self):
+ with self.assertRaisesRegex(NameError, "brown"):
+ class Color(AutoEnum):
+ red
+ green
+ blue
+ @property
+ def cap_name(self):
+ return self.name.title()
+ brown
+
+ with self.assertRaisesRegex(NameError, "rose"):
+ class Color(AutoEnum):
+ red
+ green
+ blue
+ def hello(self):
+ print('Hello! My serial is %s.' % self.value)
+ rose
+
+ with self.assertRaisesRegex(NameError, "cyan"):
+ class Color(AutoEnum):
+ red
+ green
+ blue
+ def __init__(self, *args):
+ pass
+ cyan
+
+
+class TestGenerateMethod(unittest.TestCase):
+
+ def test_autonaming(self):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ Red
+ Green
+ Blue
+ self.assertEqual(list(Color), [Color.Red, Color.Green, Color.Blue])
+ self.assertEqual(Color.Red.value, 'Red')
+ self.assertEqual(Color.Green.value, 'Green')
+ self.assertEqual(Color.Blue.value, 'Blue')
+
+ def test_autonamestr(self):
+ class Color(str, Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ Red
+ Green
+ Blue
+ self.assertTrue(isinstance(Color.Red, str))
+ self.assertEqual(Color.Green, 'Green')
+ self.assertTrue(Color.Blue < Color.Red)
+
+ def test_generate_as_staticmethod(self):
+ class Color(str, Enum):
+ @staticmethod
+ def _generate_next_value_(name, start, count, last_value):
+ return name.lower()
+ Red
+ Green
+ Blue
+ self.assertTrue(isinstance(Color.Red, str))
+ self.assertEqual(Color.Green, 'green')
+ self.assertTrue(Color.Blue < Color.Red)
+
+
+ def test_overridden_ignore(self):
+ with self.assertRaisesRegex(TypeError, "'str' object is not callable"):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ _ignore_ = ()
+ red
+ green
+ blue
+ @property
+ def whatever(self):
+ pass
+ with self.assertRaisesRegex(TypeError, "'str' object is not callable"):
+ class Color(Enum, ignore=None):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ red
+ green
+ blue
+ @property
+ def whatever(self):
+ pass
+
+ def test_property(self):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ red
+ green
+ blue
+ @property
+ def upper_name(self):
+ return self.name.upper()
+ self.assertEqual(Color.blue.upper_name, 'BLUE')
+
+ def test_magic_turns_off(self):
+ with self.assertRaisesRegex(NameError, "brown"):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ red
+ green
+ blue
+ @property
+ def cap_name(self):
+ return self.name.title()
+ brown
+
+ with self.assertRaisesRegex(NameError, "rose"):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ red
+ green
+ blue
+ def hello(self):
+ print('Hello! My value %s.' % self.value)
+ rose
+
+ with self.assertRaisesRegex(NameError, "cyan"):
+ class Color(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return name
+ red
+ green
+ blue
+ def __init__(self, *args):
+ pass
+ cyan
+
+ def test_powers_of_two(self):
+ class Bits(Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return 2 ** count
+ one
+ two
+ four
+ eight
+ self.assertEqual(Bits.one.value, 1)
+ self.assertEqual(Bits.two.value, 2)
+ self.assertEqual(Bits.four.value, 4)
+ self.assertEqual(Bits.eight.value, 8)
+
+ def test_powers_of_two_as_int(self):
+ class Bits(int, Enum):
+ def _generate_next_value_(name, start, count, last_value):
+ return 2 ** count
+ one
+ two
+ four
+ eight
+ self.assertEqual(Bits.one, 1)
+ self.assertEqual(Bits.two, 2)
+ self.assertEqual(Bits.four, 4)
+ self.assertEqual(Bits.eight, 8)
+
class TestUnique(unittest.TestCase):