Merge remote-tracking branch 'reference/2.4.0' into feature/pytest

Conflicts:
	rest_framework/runtests/urls.py
	tests/test_response.py
	tox.ini

1 files changed, 8 insertions, 10 deletions

diff --git a/rest_framework/fields.py b/rest_framework/fields.py
index 8cdc5551..8eaf763d 100644
--- a/rest_framework/fields.py
+++ b/rest_framework/fields.py
@@ -18,12 +18,14 @@ from django.conf import settings
 from django.db.models.fields import BLANK_CHOICE_DASH
 from django.http import QueryDict
 from django.forms import widgets
+from django.utils import timezone
 from django.utils.encoding import is_protected_type
 from django.utils.translation import ugettext_lazy as _
 from django.utils.datastructures import SortedDict
+from django.utils.dateparse import parse_date, parse_datetime, parse_time
 from rest_framework import ISO_8601
 from rest_framework.compat import (
-    timezone, parse_date, parse_datetime, parse_time, BytesIO, six, smart_text,
+    BytesIO, six, smart_text,
     force_text, is_non_str_iterable
 )
 from rest_framework.settings import api_settings
@@ -260,13 +262,6 @@ class WritableField(Field):
                  validators=[], error_messages=None, widget=None,
                  default=None, blank=None):
 
-        # 'blank' is to be deprecated in favor of 'required'
-        if blank is not None:
-            warnings.warn('The `blank` keyword argument is deprecated. '
-                          'Use the `required` keyword argument instead.',
-                          DeprecationWarning, stacklevel=2)
-            required = not(blank)
-
         super(WritableField, self).__init__(source=source, label=label, help_text=help_text)
 
         self.read_only = read_only
@@ -460,8 +455,9 @@ class CharField(WritableField):
     type_label = 'string'
     form_field_class = forms.CharField
 
-    def __init__(self, max_length=None, min_length=None, *args, **kwargs):
+    def __init__(self, max_length=None, min_length=None, allow_none=False, *args, **kwargs):
         self.max_length, self.min_length = max_length, min_length
+        self.allow_none = allow_none
         super(CharField, self).__init__(*args, **kwargs)
         if min_length is not None:
             self.validators.append(validators.MinLengthValidator(min_length))
@@ -469,7 +465,9 @@ class CharField(WritableField):
             self.validators.append(validators.MaxLengthValidator(max_length))
 
     def from_native(self, value):
-        if isinstance(value, six.string_types) or value is None:
+        if value is None and not self.allow_none:
+            return ''
+        if isinstance(value, six.string_types):
             return value
         return smart_text(value)