mirror of https://github.com/python/cpython
parent
c33ee85b6f
commit
6d1dece06d
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@ -734,18 +734,23 @@ class Decimal(object):
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"""
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if isinstance(f, int): # handle integer inputs
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return cls(f)
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if not isinstance(f, float):
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raise TypeError("argument must be int or float.")
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if _math.isinf(f) or _math.isnan(f):
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return cls(repr(f))
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if _math.copysign(1.0, f) == 1.0:
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sign = 0
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sign = 0 if f >= 0 else 1
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k = 0
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coeff = str(abs(f))
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elif isinstance(f, float):
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if _math.isinf(f) or _math.isnan(f):
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return cls(repr(f))
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if _math.copysign(1.0, f) == 1.0:
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sign = 0
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else:
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sign = 1
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n, d = abs(f).as_integer_ratio()
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k = d.bit_length() - 1
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coeff = str(n*5**k)
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else:
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sign = 1
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n, d = abs(f).as_integer_ratio()
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k = d.bit_length() - 1
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result = _dec_from_triple(sign, str(n*5**k), -k)
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raise TypeError("argument must be int or float.")
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result = _dec_from_triple(sign, coeff, -k)
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if cls is Decimal:
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return result
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else:
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@ -1185,6 +1185,16 @@ class FormatTest(unittest.TestCase):
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self.assertEqual(format(Decimal('100000000.123'), 'n'),
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'100\u066c000\u066c000\u066b123')
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def test_decimal_from_float_argument_type(self):
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class A(self.decimal.Decimal):
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def __init__(self, a):
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self.a_type = type(a)
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a = A.from_float(42.5)
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self.assertEqual(self.decimal.Decimal, a.a_type)
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a = A.from_float(42)
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self.assertEqual(self.decimal.Decimal, a.a_type)
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class CFormatTest(FormatTest):
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decimal = C
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class PyFormatTest(FormatTest):
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@ -10,6 +10,8 @@ What's New in Python 3.7.0 alpha 1?
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Core and Builtins
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-----------------
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- bpo-29534: Fixed different behaviour of Decimal.from_float() for _decimal and _pydecimal.
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- bpo-29438: Fixed use-after-free problem in key sharing dict.
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- Issue #29319: Prevent RunMainFromImporter overwriting sys.path[0].
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