Fixed #29534 - _decimal difference with _pydecimal (#65)

This commit is contained in:
Andrew Nester 2017-02-14 21:22:55 +03:00 committed by Mark Dickinson
parent c33ee85b6f
commit 6d1dece06d
3 changed files with 28 additions and 11 deletions

View File

@ -734,18 +734,23 @@ class Decimal(object):
"""
if isinstance(f, int): # handle integer inputs
return cls(f)
if not isinstance(f, float):
raise TypeError("argument must be int or float.")
if _math.isinf(f) or _math.isnan(f):
return cls(repr(f))
if _math.copysign(1.0, f) == 1.0:
sign = 0
sign = 0 if f >= 0 else 1
k = 0
coeff = str(abs(f))
elif isinstance(f, float):
if _math.isinf(f) or _math.isnan(f):
return cls(repr(f))
if _math.copysign(1.0, f) == 1.0:
sign = 0
else:
sign = 1
n, d = abs(f).as_integer_ratio()
k = d.bit_length() - 1
coeff = str(n*5**k)
else:
sign = 1
n, d = abs(f).as_integer_ratio()
k = d.bit_length() - 1
result = _dec_from_triple(sign, str(n*5**k), -k)
raise TypeError("argument must be int or float.")
result = _dec_from_triple(sign, coeff, -k)
if cls is Decimal:
return result
else:

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@ -1185,6 +1185,16 @@ class FormatTest(unittest.TestCase):
self.assertEqual(format(Decimal('100000000.123'), 'n'),
'100\u066c000\u066c000\u066b123')
def test_decimal_from_float_argument_type(self):
class A(self.decimal.Decimal):
def __init__(self, a):
self.a_type = type(a)
a = A.from_float(42.5)
self.assertEqual(self.decimal.Decimal, a.a_type)
a = A.from_float(42)
self.assertEqual(self.decimal.Decimal, a.a_type)
class CFormatTest(FormatTest):
decimal = C
class PyFormatTest(FormatTest):

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@ -10,6 +10,8 @@ What's New in Python 3.7.0 alpha 1?
Core and Builtins
-----------------
- bpo-29534: Fixed different behaviour of Decimal.from_float() for _decimal and _pydecimal.
- bpo-29438: Fixed use-after-free problem in key sharing dict.
- Issue #29319: Prevent RunMainFromImporter overwriting sys.path[0].