Ticket #15789: patch2.diff

django/template/defaultfilters.py

@@ -3 +3 @@
 import re
 import random as random_module
 import unicodedata
-from decimal import Decimal, InvalidOperation, ROUND_HALF_UP
+from decimal import Decimal, InvalidOperation, Context, ROUND_HALF_UP
 from functools import wraps
 from pprint import pformat
 
@@ -156 +156 @@
     else:
         exp = Decimal(u'1.0') / (Decimal(10) ** abs(p))
     try:
+        # Set the precission to the necessary digits to avoid an exception.
+        tupl = d.as_tuple()
+        units = len(tupl[1]) - tupl[2]
+        prec = abs(arg) + units + 1
+
         # Avoid conversion to scientific notation by accessing `sign`, `digits`
         # and `exponent` from `Decimal.as_tuple()` directly.
-        sign, digits, exponent = d.quantize(exp, ROUND_HALF_UP).as_tuple()
+        sign, digits, exponent = d.quantize(exp, ROUND_HALF_UP,
+                Context(prec=prec)).as_tuple()
         digits = [unicode(digit) for digit in reversed(digits)]
         while len(digits) <= abs(exponent):
             digits.append(u'0')

tests/regressiontests/defaultfilters/tests.py

@@ -1 +1 @@
 # -*- coding: utf-8 -*-
 from __future__ import with_statement
 import datetime
+import decimal
 from django.test import TestCase
 from django.utils import unittest, translation
 
@@ -18 +19 @@
         self.assertEqual(floatformat(7.7, 3), u'7.700')
         self.assertEqual(floatformat(6.000000, 3), u'6.000')
         self.assertEqual(floatformat(6.200000, 3), u'6.200')
+        self.assertEqual(floatformat(5555.555, 2), u'5555.56')
+        self.assertEqual(floatformat(001.3000, 2), u'1.30')
+        self.assertEqual(floatformat(0.12345, 2), u'0.12')
         self.assertEqual(floatformat(6.200000, -3), u'6.200')
         self.assertEqual(floatformat(13.1031, -3), u'13.103')
         self.assertEqual(floatformat(11.1197, -2), u'11.12')
@@ -31 +35 @@
         self.assertEqual(floatformat(u'¿Cómo esta usted?'), u'')
         self.assertEqual(floatformat(None), u'')
 
+        # Ignore the precision of decimal context.
+        decimal.getcontext().prec = 2
+        self.assertEqual(floatformat(1.2345, 2), u'1.23')
+        self.assertEqual(floatformat(15.2042, -3), u'15.204')
+
         # Check that we're not converting to scientific notation.
         self.assertEqual(floatformat(0, 6), u'0.000000')
         self.assertEqual(floatformat(0, 7), u'0.0000000')