Simplified implementation of django.shortcuts.render(_to_response).

*args, **kwargs brought more confusion than concision.

django/shortcuts.py

@@ -6,6 +6,9 @@ for convenience's sake.
 import warnings
 
 from django.template import loader, RequestContext
+from django.template.context import _current_app_undefined
+from django.template.engine import (
+    _context_instance_undefined, _dictionary_undefined, _dirs_undefined)
 from django.http import HttpResponse, Http404
 from django.http import HttpResponseRedirect, HttpResponsePermanentRedirect
 from django.db.models.base import ModelBase
@@ -16,49 +19,43 @@ from django.utils import six
 from django.utils.deprecation import RemovedInDjango20Warning
 
 
-def render_to_response(*args, **kwargs):
+def render_to_response(template_name, dictionary=_dictionary_undefined,
+                       context_instance=_context_instance_undefined,
+                       content_type=None, dirs=_dirs_undefined):
     """
     Returns a HttpResponse whose content is filled with the result of calling
     django.template.loader.render_to_string() with the passed arguments.
     """
-    httpresponse_kwargs = {'content_type': kwargs.pop('content_type', None)}
-
     # TODO: refactor to avoid the deprecated code path.
     with warnings.catch_warnings():
         warnings.filterwarnings("ignore", category=RemovedInDjango20Warning)
-        content = loader.render_to_string(*args, **kwargs)
+        content = loader.render_to_string(template_name, dictionary, context_instance, dirs)
 
-    return HttpResponse(content, **httpresponse_kwargs)
+    return HttpResponse(content, content_type)
 
 
-def render(request, *args, **kwargs):
+def render(request, template_name, dictionary=_dictionary_undefined,
+           context_instance=_context_instance_undefined,
+           content_type=None, status=None, current_app=_current_app_undefined,
+           dirs=_dirs_undefined):
     """
     Returns a HttpResponse whose content is filled with the result of calling
     django.template.loader.render_to_string() with the passed arguments.
     Uses a RequestContext by default.
     """
-    httpresponse_kwargs = {
-        'content_type': kwargs.pop('content_type', None),
-        'status': kwargs.pop('status', None),
-    }
-
-    if 'context_instance' in kwargs:
-        context_instance = kwargs.pop('context_instance')
-        if kwargs.get('current_app', None):
+    if context_instance is not _context_instance_undefined:
+        if current_app is not _current_app_undefined:
             raise ValueError('If you provide a context_instance you must '
                              'set its current_app before calling render()')
     else:
-        current_app = kwargs.pop('current_app', None)
         context_instance = RequestContext(request, current_app=current_app)
 
-    kwargs['context_instance'] = context_instance
-
     # TODO: refactor to avoid the deprecated code path.
     with warnings.catch_warnings():
         warnings.filterwarnings("ignore", category=RemovedInDjango20Warning)
-        content = loader.render_to_string(*args, **kwargs)
+        content = loader.render_to_string(template_name, dictionary, context_instance, dirs)
 
-    return HttpResponse(content, **httpresponse_kwargs)
+    return HttpResponse(content, content_type, status)
 
 
 def redirect(to, *args, **kwargs):

django/template/context.py

@@ -4,6 +4,8 @@ from copy import copy
 # Hard-coded processor for easier use of CSRF protection.
 _builtin_context_processors = ('django.template.context_processors.csrf',)
 
+_current_app_undefined = object()
+
 
 class ContextPopException(Exception):
     "pop() has been called more times than push()"
@@ -117,8 +119,11 @@ class BaseContext(object):
 
 class Context(BaseContext):
     "A stack container for variable context"
-    def __init__(self, dict_=None, autoescape=True, current_app=None,
+    def __init__(self, dict_=None, autoescape=True,
+            current_app=_current_app_undefined,
             use_l10n=None, use_tz=None, engine=None):
+        if current_app is _current_app_undefined:
+            current_app = None
         self.autoescape = autoescape
         self.current_app = current_app
         self.use_l10n = use_l10n
@@ -176,7 +181,8 @@ class RequestContext(Context):
     Additional processors can be specified as a list of callables
     using the "processors" keyword argument.
     """
-    def __init__(self, request, dict_=None, processors=None, current_app=None,
+    def __init__(self, request, dict_=None, processors=None,
+            current_app=_current_app_undefined,
             use_l10n=None, use_tz=None, engine=None):
         Context.__init__(self, dict_, current_app=current_app,
                 use_l10n=use_l10n, use_tz=use_tz, engine=engine)