Merge pull request #2 from Shoobx/master

Support formatting really small numbers and explicit rounding.

7 files changed, 74 insertions, 14 deletions

diff --git a/CHANGES.rst b/CHANGES.rst
index 7162443..1f40674 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,12 +5,20 @@ CHANGES
 4.2.0 (unreleased)
 ------------------
 
-- Better error message on PO-File Syntax Errors.
-  [SyZn]
+- Better error message on PO-File Syntax Errors. [SyZn]
 
-- Add support for Python 3.5.
+- Add support for Python 3.5 and 3.6.
 
-- Drop support for Python 2.6 and 3.2.
+- Drop support for Python 2.6, 3.2 and 3.3.
+
+- Support for formatting really small numbers, e.g. 1e-9. These numbers needs
+  special treatment, because standard str(x) collapses them to scientific
+  representation.
+
+- Support for specifying rounding in NumberFormatter. This is required in some
+  cases, e.g. when you format a Decimal('0.9999') that sould not be rounded.
+  Currently, formatting Decimal('0.99999') will raise a TypeError if rounding
+  is not set to False
 
 
 4.1.0 (2015-11-06)
@@ -19,6 +27,7 @@ CHANGES
 - ``interpolate()`` now works recursively, if the mapping has a value which is
   a ``zope.i18nmessageid.Message`` itself.
 
+
 4.0.1 (2015-06-05)
 --------------------
 
diff --git a/setup.py b/setup.py
index 006e0b1..8eae3ef 100644
--- a/setup.py
+++ b/setup.py
@@ -63,9 +63,9 @@ setup(
         'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: Implementation :: CPython',
         'Programming Language :: Python :: Implementation :: PyPy',
         'Natural Language :: English',
@@ -85,6 +85,7 @@ setup(
         ],
     extras_require=dict(
         test=[
+            'python-gettext',
             'zope.component [zcml]',
             'zope.configuration',
             'zope.security',
@@ -99,6 +100,7 @@ setup(
             ],
         ),
     tests_require = [
+        'python-gettext',
         'zope.component [zcml]',
         'zope.configuration',
         'zope.security',
diff --git a/src/zope/i18n/format.py b/src/zope/i18n/format.py
index 7095ece..494d09c 100644
--- a/src/zope/i18n/format.py
+++ b/src/zope/i18n/format.py
@@ -31,6 +31,9 @@ from ._compat import _u
 PY3 = sys.version_info[0] == 3
 if PY3:
     unicode = str
+    NATIVE_NUMBER_TYPES = (int, float)
+else:
+    NATIVE_NUMBER_TYPES = (int, float, long)
 
 def roundHalfUp(n):
     """Works like round() in python2.x
@@ -327,8 +330,11 @@ class NumberFormat(object):
             integer = self.symbols['nativeZeroDigit']*(min_size-size) + integer
         return integer
 
-    def _format_fraction(self, fraction, pattern):
-        max_precision = len(pattern)
+    def _format_fraction(self, fraction, pattern, rounding=True):
+        if rounding:
+            max_precision = len(pattern)
+        else:
+            max_precision = sys.maxsize
         min_precision = pattern.count('0')
         precision = len(fraction)
         roundInt = False
@@ -356,7 +362,7 @@ class NumberFormat(object):
             fraction = self.symbols['decimal'] + fraction
         return fraction, roundInt
 
-    def format(self, obj, pattern=None):
+    def format(self, obj, pattern=None, rounding=True):
         "See zope.i18n.interfaces.IFormat"
         # Make or get binary form of datetime pattern
         if pattern is not None:
@@ -369,9 +375,24 @@ class NumberFormat(object):
         else:
             bin_pattern = bin_pattern[1]
 
+        if isinstance(obj, NATIVE_NUMBER_TYPES):
+            # repr() handles high-precision numbers correctly in
+            # Python 2 and 3. str() is only correct in Python 3.
+            strobj = repr(obj)
+        else:
+            strobj = str(obj)
+        if 'e' in strobj:
+            # Str(obj) # returned scientific representation of a number (e.g.
+            # 1e-7). We can't rely on str() to format fraction.
+            decimalprec = len(bin_pattern[FRACTION]) or 1
+            obj_int, obj_frac = ("%.*f" % (decimalprec, obj)).split('.')
+            # Remove trailing 0, but leave at least one
+            obj_frac = obj_frac.rstrip("0") or "0"
+            obj_int_frac = [obj_int, obj_frac]
+        else:
+            obj_int_frac = strobj.split('.')
 
         if bin_pattern[EXPONENTIAL] != '':
-            obj_int_frac = str(obj).split('.')
             # The exponential might have a mandatory sign; remove it from the
             # bin_pattern and remember the setting
             exp_bin_pattern = bin_pattern[EXPONENTIAL]
@@ -400,7 +421,8 @@ class NumberFormat(object):
                 number = ''.join(obj_int_frac)
 
             fraction, roundInt = self._format_fraction(number[1:],
-                                                       bin_pattern[FRACTION])
+                                                       bin_pattern[FRACTION],
+                                                       rounding=rounding)
             if roundInt:
                 number = str(int(number[0]) + 1) + fraction
             else:
@@ -415,10 +437,9 @@ class NumberFormat(object):
             number += self.symbols['exponential'] + exponent
 
         else:
-            obj_int_frac = str(obj).split('.')
             if len(obj_int_frac) > 1:
-                fraction, roundInt = self._format_fraction(obj_int_frac[1],
-                                                 bin_pattern[FRACTION])
+                fraction, roundInt = self._format_fraction(
+                    obj_int_frac[1], bin_pattern[FRACTION], rounding=rounding)
             else:
                 fraction = ''
                 roundInt = False
diff --git a/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.in b/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.in
index d58a7d7..56ec799 100644
--- a/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.in
+++ b/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.in
diff --git a/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.mo b/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.mo
index 8bdb36f..56ec799 100644
--- a/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.mo
+++ b/src/zope/i18n/tests/locale3/en/LC_MESSAGES/zope-i18n.mo
diff --git a/src/zope/i18n/tests/test_formats.py b/src/zope/i18n/tests/test_formats.py
index aa7910c..ce235c3 100644
--- a/src/zope/i18n/tests/test_formats.py
+++ b/src/zope/i18n/tests/test_formats.py
@@ -1176,6 +1176,32 @@ class TestNumberFormat(TestCase):
         self.assertEqual(self.format.format(41.02, '(0.0##E0##* )* '),
                          '(4.102E1 )  ')
 
+    def testFormatSmallNumbers(self):
+        self.assertEqual(self.format.format(
+            -1e-7, '(#0.00#####);(-#0.00#####)'), '(-0.0000001)')
+        self.assertEqual(self.format.format(1e-9, '(#0.00###)'), '(0.00)')
+        self.assertEqual(self.format.format(1e-9, '(#0.00###)'), '(0.00)')
+
+    def testFormatHighPrecisionNumbers(self):
+        self.assertEqual(self.format.format(
+            1+1e-7, '(#0.00#####);(-#0.00#####)'), '(1.0000001)')
+        self.assertEqual(self.format.format(
+            1+1e-7, '(#0.00###)'), '(1.00000)')
+        self.assertEqual(self.format.format(
+            1+1e-9, '(#0.00#######);(-#0.00#######)'), '(1.000000001)')
+        self.assertEqual(self.format.format(
+            1+1e-9, '(#0.00###)'), '(1.00000)')
+        self.assertEqual(self.format.format(
+            1+1e-12, '(#0.00##########);(-#0.00##########)'),
+            '(1.000000000001)')
+        self.assertEqual(self.format.format(
+            1+1e-12, '(#0.00###)'), '(1.00000)')
+
+    def testNoRounding(self):
+        # Witout Rounding
+        self.assertEqual(self.format.format(
+            decimal.Decimal('0.99999'), '0.###', rounding=False), '0.99999')
+
 
 def test_suite():
     return TestSuite((
diff --git a/tox.ini b/tox.ini
index 17f33ed..cd5b081 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,9 @@
 [tox]
-envlist = py27,py33,py34,py35,pypy,pypy3,coverage,docs
+envlist = py27,py34,py35,py36,pypy,pypy3,coverage,docs
 
 [testenv]
+# We need to use develop egg to get namespace directories right.
+usedevelop = true
 commands =
     python setup.py -q test -q
 deps =