Revert "bpo-26680: Incorporate is_integer in all built-in and standard library numeric types (GH-6121)" (GH-22584)

This reverts commit 58a7da9e125422323f79c4ee95ac5549989d8162.

8 files changed, 1 insertions, 138 deletions

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 8c0ef57..ab989e5 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -3164,12 +3164,6 @@ class Decimal(object):
         """Return True if self is a zero; otherwise return False."""
         return not self._is_special and self._int == '0'
 
-    def is_integer(self):
-        """Return True is self is finite and integral; otherwise False."""
-        if self._is_special:
-            return False
-        return self.to_integral_value(rounding=ROUND_FLOOR) == self
-
     def _ln_exp_bound(self):
         """Compute a lower bound for the adjusted exponent of self.ln().
         In other words, compute r such that self.ln() >= 10**r.  Assumes
@@ -4665,25 +4659,6 @@ class Context(object):
         a = _convert_other(a, raiseit=True)
         return a.is_zero()
 
-    def is_integer(self, a):
-        """Return True if the operand is integral; otherwise return False.
-
-        >>> ExtendedContext.is_integer(Decimal('0'))
-        True
-        >>> ExtendedContext.is_integer(Decimal('2.50'))
-        False
-        >>> ExtendedContext.is_integer(Decimal('-0E+2'))
-        True
-        >>> ExtendedContext.is_integer(Decimal('-0.5'))
-        False
-        >>> ExtendedContext.is_integer(Decimal('NaN'))
-        False
-        >>> ExtendedContext.is_integer(10)
-        True
-        """
-        a = _convert_other(a, raiseit=True)
-        return a.is_integer()
-
     def ln(self, a):
         """Returns the natural (base e) logarithm of the operand.
 
diff --git a/Lib/numbers.py b/Lib/numbers.py
index 0634f62..ed815ef 100644
--- a/Lib/numbers.py
+++ b/Lib/numbers.py
@@ -148,7 +148,7 @@ class Real(Complex):
     """To Complex, Real adds the operations that work on real numbers.
 
     In short, those are: a conversion to float, trunc(), divmod,
-    is_integer, %, <, <=, >, and >=.
+    %, <, <=, >, and >=.
 
     Real also provides defaults for the derived operations.
     """
@@ -242,17 +242,6 @@ class Real(Complex):
         """self <= other"""
         raise NotImplementedError
 
-    def is_integer(self):
-        """Return True if the Real is integral; otherwise return False.
-
-        This default implementation can be overridden in subclasses
-        for performance reasons or to deal with values such as NaN,
-        which would otherwise cause an exception to be raised.
-        """
-        # Although __int__ is not defined at this level, the int
-        # constructor falls back to __trunc__, which we do have.
-        return self == int(self)
-
     # Concrete implementations of Complex abstract methods.
     def __complex__(self):
         """complex(self) == complex(float(self), 0)"""
@@ -301,10 +290,6 @@ class Rational(Real):
         """
         return self.numerator / self.denominator
 
-    def is_integer(self):
-        """Return True if the Rational is integral; otherwise return False."""
-        return self.denominator == 1
-
 
 class Integral(Rational):
     """Integral adds a conversion to int and the bit-string operations."""
@@ -401,8 +386,4 @@ class Integral(Rational):
         """Integers have a denominator of 1."""
         return 1
 
-    def is_integer(self):
-        """Return True; all Integrals represent an integral value."""
-        return True
-
 Integral.register(int)
diff --git a/Lib/test/decimaltestdata/extra.decTest b/Lib/test/decimaltestdata/extra.decTest
index 2f0719e..b630d8e 100644
--- a/Lib/test/decimaltestdata/extra.decTest
+++ b/Lib/test/decimaltestdata/extra.decTest
@@ -2346,24 +2346,6 @@ bool2096 iszero sNaN -> 0
 bool2097 iszero -sNaN -> 0
 bool2098 iszero sNaN123 -> 0
 bool2099 iszero -sNaN123 -> 0
-bool2100 is_integer -1.0 -> 1
-bool2101 is_integer 0.0 -> 1
-bool2102 is_integer 1.0 -> 1
-bool2103 is_integer 42 -> 1
-bool2104 is_integer 1e2 -> 1
-bool2105 is_integer 1.5 -> 0
-bool2106 is_integer 1e-2 -> 0
-bool2107 is_integer NaN -> 0
-bool2109 is_integer -NaN -> 0
-bool2110 is_integer NaN123 -> 0
-bool2111 is_integer -NaN123 -> 0
-bool2112 is_integer sNaN -> 0
-bool2113 is_integer -sNaN -> 0
-bool2114 is_integer sNaN123 -> 0
-bool2115 is_integer -sNaN123 -> 0
-bool2116 is_integer Infinity -> 0
-bool2117 is_integer -Infinity -> 0
-
 
 ------------------------------------------------------------------------
 -- The following tests (pwmx0 through pwmx440) are for the            --
diff --git a/Lib/test/test_bool.py b/Lib/test/test_bool.py
index bc201e1..7b3a385 100644
--- a/Lib/test/test_bool.py
+++ b/Lib/test/test_bool.py
@@ -354,11 +354,6 @@ class BoolTest(unittest.TestCase):
         self.assertIs(type(False.real), int)
         self.assertIs(type(False.imag), int)
 
-    def test_always_is_integer(self):
-        # Issue #26680: Incorporating number.is_integer into bool
-        self.assertTrue(all(b.is_integer() for b in (False, True)))
-
-
 def test_main():
     support.run_unittest(BoolTest)
 
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index efb41fd..dbd58e8 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -276,7 +276,6 @@ class IBMTestCases(unittest.TestCase):
                                  'is_snan',
                                  'is_subnormal',
                                  'is_zero',
-                                 'is_integer',
                                  'same_quantum')
 
     def read_unlimited(self, v, context):
@@ -2727,7 +2726,6 @@ class PythonAPItests(unittest.TestCase):
             self.assertRaises(TypeError, D(1).is_snan, context=xc)
             self.assertRaises(TypeError, D(1).is_signed, context=xc)
             self.assertRaises(TypeError, D(1).is_zero, context=xc)
-            self.assertRaises(TypeError, D(1).is_integer, context=xc)
 
             self.assertFalse(D("0.01").is_normal(context=xc))
             self.assertTrue(D("0.01").is_subnormal(context=xc))
@@ -3199,15 +3197,6 @@ class ContextAPItests(unittest.TestCase):
         self.assertEqual(c.is_zero(10), d)
         self.assertRaises(TypeError, c.is_zero, '10')
 
-    def test_is_integer(self):
-        Decimal = self.decimal.Decimal
-        Context = self.decimal.Context
-
-        c = Context()
-        b = c.is_integer(Decimal(10))
-        self.assertEqual(c.is_integer(10), b)
-        self.assertRaises(TypeError, c.is_integer, '10')
-
     def test_ln(self):
         Decimal = self.decimal.Decimal
         Context = self.decimal.Context
@@ -4371,19 +4360,6 @@ class Coverage(unittest.TestCase):
             self.assertTrue(Decimal("-1").is_signed())
             self.assertTrue(Decimal("0").is_zero())
             self.assertTrue(Decimal("0").is_zero())
-            self.assertTrue(Decimal("-1").is_integer())
-            self.assertTrue(Decimal("0").is_integer())
-            self.assertTrue(Decimal("1").is_integer())
-            self.assertTrue(Decimal("42").is_integer())
-            self.assertTrue(Decimal("1e2").is_integer())
-            self.assertFalse(Decimal("1.5").is_integer())
-            self.assertFalse(Decimal("1e-2").is_integer())
-            self.assertFalse(Decimal("NaN").is_integer())
-            self.assertFalse(Decimal("-NaN").is_integer())
-            self.assertFalse(Decimal("sNaN").is_integer())
-            self.assertFalse(Decimal("-sNaN").is_integer())
-            self.assertFalse(Decimal("Inf").is_integer())
-            self.assertFalse(Decimal("-Inf").is_integer())
 
         # Copy
         with localcontext() as c:
diff --git a/Lib/test/test_fractions.py b/Lib/test/test_fractions.py
index 811b58f..0845f79 100644
--- a/Lib/test/test_fractions.py
+++ b/Lib/test/test_fractions.py
@@ -724,17 +724,6 @@ class FractionTest(unittest.TestCase):
         self.assertEqual(type(f.numerator), myint)
         self.assertEqual(type(f.denominator), myint)
 
-    def test_is_integer(self):
-        # Issue #26680: Incorporating number.is_integer into Fraction
-        self.assertTrue(F(-1, 1).is_integer())
-        self.assertTrue(F(0, 1).is_integer())
-        self.assertTrue(F(1, 1).is_integer())
-        self.assertTrue(F(42, 1).is_integer())
-        self.assertTrue(F(2, 2).is_integer())
-        self.assertTrue(F(8, 4).is_integer())
-        self.assertFalse(F(1, 2).is_integer())
-        self.assertFalse(F(1, 3).is_integer())
-        self.assertFalse(F(2, 3).is_integer())
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/Lib/test/test_long.py b/Lib/test/test_long.py
index 669826c..c97842b 100644
--- a/Lib/test/test_long.py
+++ b/Lib/test/test_long.py
@@ -1381,10 +1381,6 @@ class LongTest(unittest.TestCase):
             self.assertEqual(type(numerator), int)
             self.assertEqual(type(denominator), int)
 
-    def test_int_always_is_integer(self):
-        # Issue #26680: Incorporating number.is_integer into int
-        self.assertTrue(all(x.is_integer() for x in (-1, 0, 1, 42)))
-
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/Lib/test/test_numeric_tower.py b/Lib/test/test_numeric_tower.py
index 4e46aac..c54dedb 100644
--- a/Lib/test/test_numeric_tower.py
+++ b/Lib/test/test_numeric_tower.py
@@ -6,7 +6,6 @@ import math
 import sys
 import operator
 
-from numbers import Real, Rational, Integral
 from decimal import Decimal as D
 from fractions import Fraction as F
 
@@ -199,35 +198,5 @@ class ComparisonTest(unittest.TestCase):
                 self.assertRaises(TypeError, op, v, z)
 
 
-class IsIntegerTest(unittest.TestCase):
-
-    def test_real_is_integer(self):
-        self.assertTrue(Real.is_integer(-1.0))
-        self.assertTrue(Real.is_integer(0.0))
-        self.assertTrue(Real.is_integer(1.0))
-        self.assertTrue(Real.is_integer(42.0))
-
-        self.assertFalse(Real.is_integer(-0.5))
-        self.assertFalse(Real.is_integer(4.2))
-
-    def test_rational_is_integer(self):
-        self.assertTrue(Rational.is_integer(F(-1, 1)))
-        self.assertTrue(Rational.is_integer(F(0, 1)))
-        self.assertTrue(Rational.is_integer(F(1, 1)))
-        self.assertTrue(Rational.is_integer(F(42, 1)))
-        self.assertTrue(Rational.is_integer(F(2, 2)))
-        self.assertTrue(Rational.is_integer(F(8, 4)))
-
-        self.assertFalse(Rational.is_integer(F(1, 2)))
-        self.assertFalse(Rational.is_integer(F(1, 3)))
-        self.assertFalse(Rational.is_integer(F(2, 3)))
-
-    def test_integral_is_integer(self):
-        self.assertTrue(Integral.is_integer(-1))
-        self.assertTrue(Integral.is_integer(0))
-        self.assertTrue(Integral.is_integer(1))
-        self.assertTrue(Integral.is_integer(1729))
-
-
 if __name__ == '__main__':
     unittest.main()