| # -*- coding: utf-8 -*- |
| """ |
| jinja2.runtime |
| ~~~~~~~~~~~~~~ |
| |
| Runtime helpers. |
| |
| :copyright: Copyright 2008 by Armin Ronacher. |
| :license: GNU GPL. |
| """ |
| try: |
| from collections import defaultdict |
| except ImportError: |
| defaultdict = None |
| |
| |
| __all__ = ['extends', 'subscribe', 'LoopContext', 'TemplateContext', 'Macro'] |
| |
| |
| def extends(template, namespace): |
| """This loads a template (and evaluates it) and replaces the blocks.""" |
| |
| |
| def subscribe(obj, argument, undefined_factory): |
| """Get an item or attribute of an object.""" |
| try: |
| return getattr(obj, str(argument)) |
| except (AttributeError, UnicodeError): |
| try: |
| return obj[argument] |
| except LookupError: |
| return undefined_factory(attr=argument) |
| |
| |
| class TemplateContext(dict): |
| """ |
| Holds the variables of the local template or of the global one. It's |
| not save to use this class outside of the compiled code. For example |
| update and other methods will not work as they seem (they don't update |
| the exported variables for example). |
| """ |
| |
| def __init__(self, globals, undefined_factory, filename): |
| dict.__init__(self, globals) |
| self.exported = set() |
| self.undefined_factory = undefined_factory |
| self.filename = filename |
| self.filters = {} |
| self.tests = {} |
| |
| def __setitem__(self, key, value): |
| """If we set items to the dict we track the variables set so |
| that includes can access the exported variables.""" |
| dict.__setitem__(self, key, value) |
| self.exported.add(key) |
| |
| def __delitem__(self, key): |
| """On delete we no longer export it.""" |
| dict.__delitem__(self, key) |
| self.exported.dicard(key) |
| |
| def get_exported(self): |
| """Get a dict of all exported variables.""" |
| return dict((k, self[k]) for k in self.exported) |
| |
| # if there is a default dict, dict has a __missing__ method we can use. |
| if defaultdict is None: |
| def __getitem__(self, name): |
| if name in self: |
| return self[name] |
| return self.undefined_factory(name) |
| else: |
| def __missing__(self, key): |
| return self.undefined_factory(key) |
| |
| |
| class LoopContext(object): |
| """Helper for extended iteration.""" |
| |
| def __init__(self, iterable, parent=None): |
| self._iterable = iterable |
| self.index0 = 0 |
| self.parent = parent |
| |
| def __iter__(self): |
| for item in self._iterable: |
| yield self, item |
| self.index0 += 1 |
| |
| first = property(lambda x: x.index0 == 0) |
| last = property(lambda x: x.revindex0 == 0) |
| index = property(lambda x: x.index0 + 1) |
| revindex = property(lambda x: x.length) |
| revindex0 = property(lambda x: x.length - 1) |
| |
| @property |
| def length(self): |
| if not hasattr(self, '_length'): |
| try: |
| length = len(self._iterable) |
| except TypeError: |
| length = len(tuple(self._iterable)) |
| self._length = length |
| return self._length |
| |
| |
| class Macro(object): |
| """ |
| Wraps a macor |
| """ |
| |
| def __init__(self, func, name, arguments, defaults, catch_all, \ |
| undefined_factory): |
| self.func = func |
| self.name = name |
| self.arguments = arguments |
| self.defaults = defaults |
| self.catch_all = catch_all |
| self.undefined_factory = undefined_factory |
| |
| def __call__(self, *args, **kwargs): |
| arg_count = len(self.arguments) |
| if len(args) > arg_count: |
| raise TypeError('macro %r takes not more than %d argument(s).' % |
| (self.name, len(self.arguments))) |
| arguments = {} |
| for idx, name in enumerate(self.arguments): |
| try: |
| value = args[idx] |
| except IndexError: |
| try: |
| value = kwargs.pop(name) |
| except KeyError: |
| try: |
| value = self.defaults[idx - arg_count] |
| except IndexError: |
| value = self.undefined_factory(name) |
| arguments['l_' + name] = arg |
| if self.catch_all: |
| arguments['l_arguments'] = kwargs |
| return u''.join(self.func(**arguments)) |