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

This reverts commit 58a7da9e125422323f79c4ee95ac5549989d8162.

16 files changed, 24 insertions, 223 deletions

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 7a64973059..e194649e30 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -621,13 +621,6 @@ Decimal objects
       Return :const:`True` if the argument is either positive or negative
       infinity and :const:`False` otherwise.
 
-   .. method:: is_integer()
-
-      Return :const:`True` if the argument is a finite integral value and
-      :const:`False` otherwise.
-
-      .. versionadded:: 3.10
-
    .. method:: is_nan()
 
       Return :const:`True` if the argument is a (quiet or signaling) NaN and
@@ -1222,13 +1215,6 @@ In addition to the three supplied contexts, new contexts can be created with the
       Returns ``True`` if *x* is infinite; otherwise returns ``False``.
 
 
-   .. method:: is_integer(x)
-
-      Returns ``True`` if *x* is finite and integral; otherwise
-      returns ``False``.
-
-      .. versionadded:: 3.10
-
    .. method:: is_nan(x)
 
       Returns ``True`` if *x* is a qNaN or sNaN; otherwise returns ``False``.
diff --git a/Doc/library/numbers.rst b/Doc/library/numbers.rst
index 5d49f5eb96..1b594952ea 100644
--- a/Doc/library/numbers.rst
+++ b/Doc/library/numbers.rst
@@ -49,30 +49,19 @@ The numeric tower
    numbers.
 
    In short, those are: a conversion to :class:`float`, :func:`math.trunc`,
-   :func:`round`, :func:`math.floor`, :func:`math.ceil`, :func:`divmod`,
-   :func:`~Real.is_integer`, ``//``, ``%``, ``<``, ``<=``, ``>``, and ``>=``.
+   :func:`round`, :func:`math.floor`, :func:`math.ceil`, :func:`divmod`, ``//``,
+   ``%``, ``<``, ``<=``, ``>``, and ``>=``.
 
    Real also provides defaults for :func:`complex`, :attr:`~Complex.real`,
    :attr:`~Complex.imag`, and :meth:`~Complex.conjugate`.
 
-   .. method:: is_integer()
-
-      Returns :const:`True` if this number has a finite and integral value,
-      otherwise :const:`False`.  This is a default implementation which
-      relies on successful conversion to :class:`int`. It may be overridden
-      in subclasses (such as it is in :class:`float`) for better performance,
-      or to handle special values such as NaN which are not
-      convertible to :class:`int`.
-
-      .. versionadded:: 3.10
-
 
 .. class:: Rational
 
    Subtypes :class:`Real` and adds
    :attr:`~Rational.numerator` and :attr:`~Rational.denominator` properties, which
-   should be in lowest terms. With these, it provides defaults for
-   :func:`float` and :func:`~Real.is_integer`.
+   should be in lowest terms. With these, it provides a default for
+   :func:`float`.
 
    .. attribute:: numerator
 
@@ -86,10 +75,9 @@ The numeric tower
 .. class:: Integral
 
    Subtypes :class:`Rational` and adds a conversion to :class:`int`.  Provides
-   defaults for :func:`float`, :attr:`~Rational.numerator`,
-   :attr:`~Rational.denominator`, and :func:`~Real.is_integer`.  Adds abstract
-   methods for ``**`` and bit-string operations: ``<<``, ``>>``, ``&``, ``^``,
-   ``|``, ``~``.
+   defaults for :func:`float`, :attr:`~Rational.numerator`, and
+   :attr:`~Rational.denominator`.  Adds abstract methods for ``**`` and
+   bit-string operations: ``<<``, ``>>``, ``&``, ``^``, ``|``, ``~``.
 
 
 Notes for type implementors
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 04dfea276d..5c6acc66bb 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -310,10 +310,6 @@ the operations, see :ref:`operator-summary`):
 +---------------------+---------------------------------+---------+--------------------+
 | ``x ** y``          | *x* to the power *y*            | \(5)    |                    |
 +---------------------+---------------------------------+---------+--------------------+
-| ``x.is_integer()``  | ``True`` if *x* has a finite    |         | :func:`~numbers\   |
-|                     | and integral value, otherwise   |         | .Real.is_integer`  |
-|                     | ``False``.                      |         |                    |
-+---------------------+---------------------------------+---------+--------------------+
 
 .. index::
    triple: operations on; numeric; types
@@ -587,6 +583,16 @@ class`. float also has the following additional methods.
    :exc:`OverflowError` on infinities and a :exc:`ValueError` on
    NaNs.
 
+.. method:: float.is_integer()
+
+   Return ``True`` if the float instance is finite with integral
+   value, and ``False`` otherwise::
+
+      >>> (-2.0).is_integer()
+      True
+      >>> (3.2).is_integer()
+      False
+
 Two methods support conversion to
 and from hexadecimal strings.  Since Python's floats are stored
 internally as binary numbers, converting a float to or from a
diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 8c0ef57092..ab989e5206 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 0634f62ff1..ed815ef41e 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 2f0719ed22..b630d8e3f9 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 bc201e10ff..7b3a3859e0 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 efb41fd465..dbd58e8a65 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 811b58fd8f..0845f7921c 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 669826c0fa..c97842b5bf 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 4e46aacad8..c54dedb8b7 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()
diff --git a/Misc/ACKS b/Misc/ACKS
index 08449fe082..cffcc6bcd7 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1612,7 +1612,6 @@ Roman Skurikhin
 Ville Skyttä
 Michael Sloan
 Nick Sloan
-Robert Smallshire
 Václav Šmilauer
 Allen W. Smith
 Christopher Smith
diff --git a/Modules/_decimal/_decimal.c b/Modules/_decimal/_decimal.c
index 5200b1a48e..e7c44acba0 100644
--- a/Modules/_decimal/_decimal.c
+++ b/Modules/_decimal/_decimal.c
@@ -4138,7 +4138,6 @@ Dec_BoolFunc(mpd_isqnan)
 Dec_BoolFunc(mpd_issnan)
 Dec_BoolFunc(mpd_issigned)
 Dec_BoolFunc(mpd_iszero)
-Dec_BoolFunc(mpd_isinteger)
 
 /* Boolean functions, optional context arg */
 Dec_BoolFuncVA(mpd_isnormal)
@@ -4773,7 +4772,6 @@ static PyMethodDef dec_methods [] =
   { "is_snan", dec_mpd_issnan, METH_NOARGS, doc_is_snan },
   { "is_signed", dec_mpd_issigned, METH_NOARGS, doc_is_signed },
   { "is_zero", dec_mpd_iszero, METH_NOARGS, doc_is_zero },
-  { "is_integer", dec_mpd_isinteger, METH_NOARGS, doc_is_integer},
 
   /* Boolean functions, optional context arg */
   { "is_normal", (PyCFunction)(void(*)(void))dec_mpd_isnormal, METH_VARARGS|METH_KEYWORDS, doc_is_normal },
@@ -5185,7 +5183,6 @@ DecCtx_BoolFunc_NO_CTX(mpd_isqnan)
 DecCtx_BoolFunc_NO_CTX(mpd_issigned)
 DecCtx_BoolFunc_NO_CTX(mpd_issnan)
 DecCtx_BoolFunc_NO_CTX(mpd_iszero)
-DecCtx_BoolFunc_NO_CTX(mpd_isinteger)
 
 static PyObject *
 ctx_iscanonical(PyObject *context UNUSED, PyObject *v)
@@ -5467,7 +5464,6 @@ static PyMethodDef context_methods [] =
   { "is_snan", ctx_mpd_issnan, METH_O, doc_ctx_is_snan },
   { "is_subnormal", ctx_mpd_issubnormal, METH_O, doc_ctx_is_subnormal },
   { "is_zero", ctx_mpd_iszero, METH_O, doc_ctx_is_zero },
-  { "is_integer", ctx_mpd_isinteger, METH_O, doc_ctx_is_integer },
 
   /* Functions with a single decimal argument */
   { "_apply", PyDecContext_Apply, METH_O, NULL }, /* alias for apply */
@@ -6101,3 +6097,5 @@ error:
 
     return NULL; /* GCOV_NOT_REACHED */
 }
+
+
diff --git a/Modules/_decimal/docstrings.h b/Modules/_decimal/docstrings.h
index bd602ab278..f7fd6e7952 100644
--- a/Modules/_decimal/docstrings.h
+++ b/Modules/_decimal/docstrings.h
@@ -260,11 +260,6 @@ Return True if the argument is a (positive or negative) zero and False\n\
 otherwise.\n\
 \n");
 
-PyDoc_STRVAR(doc_is_integer,
-"is_integer($self, /)\n--\n\n\
-Return True if the argument is finite and integral, otherwise False.\n\
-\n");
-
 PyDoc_STRVAR(doc_ln,
 "ln($self, /, context=None)\n--\n\n\
 Return the natural (base e) logarithm of the operand. The function always\n\
@@ -690,11 +685,6 @@ PyDoc_STRVAR(doc_ctx_is_zero,
 Return True if x is a zero, False otherwise.\n\
 \n");
 
-PyDoc_STRVAR(doc_ctx_is_integer,
-"is_integer($self, x, /)\n--\n\n\
-+Return True if x is finite and integral, False otherwise.\n\
-+\n");
-
 PyDoc_STRVAR(doc_ctx_ln,
 "ln($self, x, /)\n--\n\n\
 Return the natural (base e) logarithm of x.\n\
@@ -889,3 +879,6 @@ Convert a number to a string using scientific notation.\n\
 
 
 #endif /* DOCSTRINGS_H */
+
+
+
diff --git a/Objects/clinic/longobject.c.h b/Objects/clinic/longobject.c.h
index 16e6f7e619..4bd47b116f 100644
--- a/Objects/clinic/longobject.c.h
+++ b/Objects/clinic/longobject.c.h
@@ -121,24 +121,6 @@ exit:
     return return_value;
 }
 
-PyDoc_STRVAR(int_is_integer__doc__,
-"is_integer($self, /)\n"
-"--\n"
-"\n"
-"Returns True for all integers.");
-
-#define INT_IS_INTEGER_METHODDEF    \
-    {"is_integer", (PyCFunction)int_is_integer, METH_NOARGS, int_is_integer__doc__},
-
-static PyObject *
-int_is_integer_impl(PyObject *self);
-
-static PyObject *
-int_is_integer(PyObject *self, PyObject *Py_UNUSED(ignored))
-{
-    return int_is_integer_impl(self);
-}
-
 PyDoc_STRVAR(int___sizeof____doc__,
 "__sizeof__($self, /)\n"
 "--\n"
@@ -385,4 +367,4 @@ skip_optional_kwonly:
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=022614978e2fcdf3 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ea18e51af5b53591 input=a9049054013a1b77]*/
diff --git a/Objects/longobject.c b/Objects/longobject.c
index bc5b49dcf8..92514d4154 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -5234,19 +5234,6 @@ int___round___impl(PyObject *self, PyObject *o_ndigits)
 }
 
 /*[clinic input]
-int.is_integer
-
-Returns True for all integers.
-[clinic start generated code]*/
-
-static PyObject *
-int_is_integer_impl(PyObject *self)
-/*[clinic end generated code: output=90f8e794ce5430ef input=1c1a86957301d26d]*/
-{
-    Py_RETURN_TRUE;
-}
-
-/*[clinic input]
 int.__sizeof__ -> Py_ssize_t
 
 Returns size in memory, in bytes.
@@ -5560,7 +5547,6 @@ static PyMethodDef long_methods[] = {
     {"__ceil__",        long_long_meth, METH_NOARGS,
      "Ceiling of an Integral returns itself."},
     INT___ROUND___METHODDEF
-    INT_IS_INTEGER_METHODDEF
     INT___GETNEWARGS___METHODDEF
     INT___FORMAT___METHODDEF
     INT___SIZEOF___METHODDEF