bpo-33073: Adding as_integer_ratio to ints.

Doc/library/stdtypes.rst

@@ -539,6 +539,12 @@ class`. In addition, it provides a few more methods:
 
     .. versionadded:: 3.2
 
+.. method:: int.as_integer_ratio()
+
+  Return a pair of integers whose ratio is exactly equal to the original integer
+  and with a positive denominator. The integer ratio of integers (whole numbers)
+  is always the integer as the numerator and 1 as the denominator.
+
 
 Additional Methods on Float
 ---------------------------
@@ -4734,4 +4740,3 @@ types, where they are relevant.  Some of these are not reported by the
 
 .. [5] To format only a tuple you should therefore provide a singleton tuple whose only
    element is the tuple to be formatted.
-

Lib/test/test_long.py

@@ -1349,6 +1349,11 @@ def test_shift_bool(self):
                 self.assertEqual(type(value << shift), int)
                 self.assertEqual(type(value >> shift), int)
 
+    def test_as_integer_ratio(self):
+        tests = [10, 0, -10, 1, 3]
+        for value in tests:
+            self.assertEqual((value).as_integer_ratio(), (value, 1))
+
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Core and Builtins/2018-08-12-16-03-58.bpo-33073.XWu1Jh.rst

@@ -0,0 +1 @@
+Added as_integer_ratio to ints to make them more interoperable with floats.

Objects/longobject.c

@@ -5260,6 +5260,40 @@ long_is_finite(PyObject *v)
 }
 #endif
 
+/*[clinic input]
+int.as_integer_ratio
+
+Return integer ratio.
+
+Return a pair of integers, whose ratio is exactly equal to the original int
+and with a positive denominator.
+
+Raise OverflowError on infinities and a ValueError on NaNs.
+
+>>> (10).as_integer_ratio()
+(10, 1)
+>>> (0).as_integer_ratio()
+(0, 1)
+>>> (11).as_integer_ratio()
+(11, 1)
+>>> (-10).as_integer_ratio()
+(-10, 1)
+[clinic start generated code]*/
+
+static PyObject *
+int_as_integer_ratio_impl(PyObject *self)
+/*[clinic end generated code: output=e60803ae1cc8621a input=ce9c7768a1287fb9]*/
+{
+    PyObject *denominator = NULL;
+    PyObject *result_pair = NULL;
+
+    denominator = PyLong_FromLong(1);
+    result_pair = PyTuple_Pack(2, self, denominator);
+
+    Py_DECREF(denominator);
+    return result_pair;
+}
+
 /*[clinic input]
 int.to_bytes
 
@@ -5392,6 +5426,7 @@ static PyMethodDef long_methods[] = {
 #endif
     INT_TO_BYTES_METHODDEF
     INT_FROM_BYTES_METHODDEF
+    INT_AS_INTEGER_RATIO_METHODDEF
     {"__trunc__",       long_long_meth, METH_NOARGS,
      "Truncating an Integral returns itself."},
     {"__floor__",       long_long_meth, METH_NOARGS,