test_locale now ignores the DeprecationWarning (#977)

Don't fail anymore if test run with python3 -Werror.

Fix also deprecation message: add a space.

Lib/locale.py

@@ -245,7 +245,7 @@ def format_string(f, val, grouping=False, monetary=False):
 def format(percent, value, grouping=False, monetary=False, *additional):
     """Deprecated, use format_string instead."""
     warnings.warn(
-        "This method will be removed in a future version of Python."
+        "This method will be removed in a future version of Python. "
         "Use 'locale.format_string()' instead.",
         DeprecationWarning, stacklevel=2
     )

Lib/test/test_locale.py

-from test.support import verbose, is_android
+from test.support import verbose, is_android, check_warnings
 import unittest
 import locale
 import sys
@@ -144,6 +144,7 @@ class BaseFormattingTest(object):
             func(format, value, **format_opts), out)
 
     def _test_format(self, format, value, out, **format_opts):
+        with check_warnings(('', DeprecationWarning)):
             self._test_formatfunc(format, value, out,
                 func=locale.format, **format_opts)
 
@@ -232,6 +233,7 @@ class TestFormatPatternArg(unittest.TestCase):
     # Test handling of pattern argument of format
 
     def test_onlyOnePattern(self):
+        with check_warnings(('', DeprecationWarning)):
             # Issue 2522: accept exactly one % pattern, and no extra chars.
             self.assertRaises(ValueError, locale.format, "%f\n", 'foo')
             self.assertRaises(ValueError, locale.format, "%f\r", 'foo')