--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/django/template/context.py	Wed Jun 02 18:57:35 2010 +0200
@@ -0,0 +1,149 @@
+from django.core.exceptions import ImproperlyConfigured
+from django.utils.importlib import import_module
+
+# Cache of actual callables.
+_standard_context_processors = None
+# We need the CSRF processor no matter what the user has in their settings,
+# because otherwise it is a security vulnerability, and we can't afford to leave
+# this to human error or failure to read migration instructions.
+_builtin_context_processors =  ('django.core.context_processors.csrf',)
+
+class ContextPopException(Exception):
+    "pop() has been called more times than push()"
+    pass
+
+class BaseContext(object):
+    def __init__(self, dict_=None):
+        dict_ = dict_ or {}
+        self.dicts = [dict_]
+
+    def __repr__(self):
+        return repr(self.dicts)
+
+    def __iter__(self):
+        for d in reversed(self.dicts):
+            yield d
+
+    def push(self):
+        d = {}
+        self.dicts.append(d)
+        return d
+
+    def pop(self):
+        if len(self.dicts) == 1:
+            raise ContextPopException
+        return self.dicts.pop()
+
+    def __setitem__(self, key, value):
+        "Set a variable in the current context"
+        self.dicts[-1][key] = value
+
+    def __getitem__(self, key):
+        "Get a variable's value, starting at the current context and going upward"
+        for d in reversed(self.dicts):
+            if key in d:
+                return d[key]
+        raise KeyError(key)
+
+    def __delitem__(self, key):
+        "Delete a variable from the current context"
+        del self.dicts[-1][key]
+
+    def has_key(self, key):
+        for d in self.dicts:
+            if key in d:
+                return True
+        return False
+
+    def __contains__(self, key):
+        return self.has_key(key)
+
+    def get(self, key, otherwise=None):
+        for d in reversed(self.dicts):
+            if key in d:
+                return d[key]
+        return otherwise
+
+class Context(BaseContext):
+    "A stack container for variable context"
+    def __init__(self, dict_=None, autoescape=True, current_app=None):
+        self.autoescape = autoescape
+        self.current_app = current_app
+        self.render_context = RenderContext()
+        super(Context, self).__init__(dict_)
+
+    def update(self, other_dict):
+        "Like dict.update(). Pushes an entire dictionary's keys and values onto the context."
+        if not hasattr(other_dict, '__getitem__'):
+            raise TypeError('other_dict must be a mapping (dictionary-like) object.')
+        self.dicts.append(other_dict)
+        return other_dict
+
+class RenderContext(BaseContext):
+    """
+    A stack container for storing Template state.
+
+    RenderContext simplifies the implementation of template Nodes by providing a
+    safe place to store state between invocations of a node's `render` method.
+
+    The RenderContext also provides scoping rules that are more sensible for
+    'template local' variables. The render context stack is pushed before each
+    template is rendered, creating a fresh scope with nothing in it. Name
+    resolution fails if a variable is not found at the top of the RequestContext
+    stack. Thus, variables are local to a specific template and don't affect the
+    rendering of other templates as they would if they were stored in the normal
+    template context.
+    """
+    def __iter__(self):
+        for d in self.dicts[-1]:
+            yield d
+
+    def has_key(self, key):
+        return key in self.dicts[-1]
+
+    def get(self, key, otherwise=None):
+        d = self.dicts[-1]
+        if key in d:
+            return d[key]
+        return otherwise
+
+# This is a function rather than module-level procedural code because we only
+# want it to execute if somebody uses RequestContext.
+def get_standard_processors():
+    from django.conf import settings
+    global _standard_context_processors
+    if _standard_context_processors is None:
+        processors = []
+        collect = []
+        collect.extend(_builtin_context_processors)
+        collect.extend(settings.TEMPLATE_CONTEXT_PROCESSORS)
+        for path in collect:
+            i = path.rfind('.')
+            module, attr = path[:i], path[i+1:]
+            try:
+                mod = import_module(module)
+            except ImportError, e:
+                raise ImproperlyConfigured('Error importing request processor module %s: "%s"' % (module, e))
+            try:
+                func = getattr(mod, attr)
+            except AttributeError:
+                raise ImproperlyConfigured('Module "%s" does not define a "%s" callable request processor' % (module, attr))
+            processors.append(func)
+        _standard_context_processors = tuple(processors)
+    return _standard_context_processors
+
+class RequestContext(Context):
+    """
+    This subclass of template.Context automatically populates itself using
+    the processors defined in TEMPLATE_CONTEXT_PROCESSORS.
+    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):
+        Context.__init__(self, dict, current_app=current_app)
+        if processors is None:
+            processors = ()
+        else:
+            processors = tuple(processors)
+        for processor in get_standard_processors() + processors:
+            self.update(processor(request))