use decimal.Decimal instead of float to store amounts of money

weboob/capabilities/bank.py

@@ -20,7 +20,7 @@
 
 from datetime import date, datetime
 
-from .base import CapBaseObject, Field, StringField, DateField, FloatField, IntField
+from .base import CapBaseObject, Field, StringField, DateField, DecimalField, IntField
 from .collection import ICapCollection
 
 
@@ -66,8 +66,8 @@ class Account(Recipient):
     TYPE_JOINT            = 6  # Joint account
 
     type =      IntField('Type of account', default=TYPE_UNKNOWN)
-    balance =   FloatField('Balance on this bank account')
-    coming =    FloatField('Coming balance')
+    balance =   DecimalField('Balance on this bank account')
+    coming =    DecimalField('Coming balance')
 
     def __repr__(self):
         return u"<Account id=%r label=%r>" % (self.id, self.label)
@@ -94,7 +94,7 @@ class Transaction(CapBaseObject):
     raw =       StringField('Raw label of the transaction')
     category =  StringField('Category of transaction')
     label =     StringField('Pretty label')
-    amount =    FloatField('Amount of transaction')
+    amount =    DecimalField('Amount of transaction')
 
     def __repr__(self):
         return "<Transaction date='%s' label='%s' amount=%s>" % (self.date,
@@ -105,7 +105,7 @@ class Transfer(CapBaseObject):
     Transfer from an account to a recipient.
     """
 
-    amount =    FloatField('Amount to transfer')
+    amount =    DecimalField('Amount to transfer')
     date =      Field('Date of transfer', basestring, date, datetime)
     origin =    Field('Origin of transfer', int, long, basestring)
     recipient = Field('Recipient', int, long, basestring)
@@ -193,7 +193,7 @@ class ICapBank(ICapCollection):
         :param recipient: account to send money
         :type recipient: :class:`Recipient`
         :param amount: amount
-        :type amount: :class:`float`
+        :type amount: :class:`decimal.Decimal`
         :param reason: reason of transfer
         :type reason: :class:`unicode`
         :rtype: :class:`Transfer`

weboob/capabilities/base.py

@@ -20,6 +20,7 @@
 
 import warnings
 import datetime
+from decimal import Decimal
 from copy import deepcopy
 
 from weboob.tools.misc import to_unicode
@@ -27,8 +28,8 @@ from weboob.tools.ordereddict import OrderedDict
 
 
 __all__ = ['FieldNotFound', 'NotAvailable', 'NotLoaded', 'IBaseCap',
-           'Field', 'IntField', 'FloatField', 'StringField', 'BytesField',
-           'DateField', 'DeltaField', 'CapBaseObject', 'empty']
+           'Field', 'IntField', 'DecimalField', 'FloatField', 'StringField',
+           'BytesField', 'DateField', 'DeltaField', 'CapBaseObject', 'empty']
 
 
 def empty(value):
@@ -154,6 +155,18 @@ class IntField(Field):
     def convert(self, value):
         return int(value)
 
+class DecimalField(Field):
+    """
+    A field which accepts only :class:`decimal` type.
+    """
+    def __init__(self, doc, **kwargs):
+        Field.__init__(self, doc, Decimal, **kwargs)
+
+    def convert(self, value):
+        if isinstance(value, Decimal):
+            return value
+        return Decimal(value)
+
 class FloatField(Field):
     """
     A field which accepts only :class:`float` type.
@@ -244,7 +257,7 @@ class CapBaseObject(object):
         class Transfer(CapBaseObject):
             " Transfer from an account to a recipient.  "
 
-            amount =    FloatField('Amount to transfer')
+            amount =    DecimalField('Amount to transfer')
             date =      Field('Date of transfer', basestring, date, datetime)
             origin =    Field('Origin of transfer', int, long, basestring)
             recipient = Field('Recipient', int, long, basestring)

weboob/capabilities/bill.py

@@ -17,7 +17,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with weboob. If not, see <http://www.gnu.org/licenses/>.
 
-from .base import CapBaseObject, StringField, DateField, FloatField
+from .base import CapBaseObject, StringField, DateField, DecimalField
 from .collection import ICapCollection
 
 
@@ -47,7 +47,7 @@ class Detail(CapBaseObject):
     label =     StringField('label of the detail line')
     infos =     StringField('information')
     datetime =  DateField('date information')
-    price =     FloatField('price')
+    price =     DecimalField('price')
 
     def __init__(self):
         CapBaseObject.__init__(self, 0)

weboob/capabilities/housing.py

@@ -18,7 +18,7 @@
 # along with weboob. If not, see <http://www.gnu.org/licenses/>.
 
 
-from .base import IBaseCap, CapBaseObject, Field, IntField, FloatField, \
+from .base import IBaseCap, CapBaseObject, Field, IntField, DecimalField, \
                   StringField, BytesField, DateField
 
 
@@ -50,8 +50,8 @@ class Housing(CapBaseObject):
     Content of a housing.
     """
     title =         StringField('Title of housing')
-    area =          FloatField('Area of housing, in m2')
-    cost =          FloatField('Cost of housing')
+    area =          DecimalField('Area of housing, in m2')
+    cost =          DecimalField('Cost of housing')
     currency =      StringField('Currency of cost')
     date =          DateField('Date when the housing has been published')
     location =      StringField('Location of housing')

weboob/capabilities/pricecomparison.py

@@ -18,7 +18,7 @@
 # along with weboob. If not, see <http://www.gnu.org/licenses/>.
 
 
-from .base import IBaseCap, CapBaseObject, Field, FloatField, \
+from .base import IBaseCap, CapBaseObject, Field, DecimalField, \
                   StringField, DateField
 
 
@@ -44,7 +44,7 @@ class Price(CapBaseObject):
     Price.
     """
     date =      DateField('Date when this price has been published')
-    cost =      FloatField('Cost of the product in this shop')
+    cost =      DecimalField('Cost of the product in this shop')
     currency =  StringField('Currency of the price')
     message =   StringField('Message related to this price')
     shop =      Field('Shop information', Shop)