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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -1,18 +1,19 @@ """ Backports the ``register.assignment_tag`` functionality from Django 1.4 to Django 1.3. This code is almost entirely reproduced from https://code.djangoproject.com/browser/django/trunk/django/template/base.py and is the work of Django's authors: https://code.djangoproject.com/browser/django/trunk/AUTHORS It is licensed under Django's BSD license, available here: https://code.djangoproject.com/browser/django/trunk/LICENSE To use, simply import this code in your project prior to using the ``register.assignment_tag``. In general, the top of your template tag python file would be a good place for the import. """ import re from inspect import getargspec -
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -1,3 +1,16 @@ """ Adds the register.assignment_tag functionality from Django 1.4 to Django 1.3. This code is almost entirely reproduced from https://code.djangoproject.com/browser/django/trunk/django/template/base.py and is the work of Django's authors. It is licensed under a BSD license as per Django's license available here: https://code.djangoproject.com/browser/django/trunk/LICENSE To use, simply import this code in your project prior to using the assignment_tag decorator. In general, the top of your template tag python file would be a good place for the import. """ from __future__ import absolute_import import re -
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,195 @@ from __future__ import absolute_import import re from inspect import getargspec from django.template import TemplateSyntaxError from django.template.base import Node, Library if not hasattr(Library, 'assignment_tag'): # Regex for token keyword arguments kwarg_re = re.compile(r"(?:(\w+)=)?(.+)") def token_kwargs(bits, parser, support_legacy=False): """ A utility method for parsing token keyword arguments. :param bits: A list containing remainder of the token (split by spaces) that is to be checked for arguments. Valid arguments will be removed from this list. :param support_legacy: If set to true ``True``, the legacy format ``1 as foo`` will be accepted. Otherwise, only the standard ``foo=1`` format is allowed. :returns: A dictionary of the arguments retrieved from the ``bits`` token list. There is no requirement for all remaining token ``bits`` to be keyword arguments, so the dictionary will be returned as soon as an invalid argument format is reached. """ if not bits: return {} match = kwarg_re.match(bits[0]) kwarg_format = match and match.group(1) if not kwarg_format: if not support_legacy: return {} if len(bits) < 3 or bits[1] != 'as': return {} kwargs = {} while bits: if kwarg_format: match = kwarg_re.match(bits[0]) if not match or not match.group(1): return kwargs key, value = match.groups() del bits[:1] else: if len(bits) < 3 or bits[1] != 'as': return kwargs key, value = bits[2], bits[0] del bits[:3] kwargs[key] = parser.compile_filter(value) if bits and not kwarg_format: if bits[0] != 'and': return kwargs del bits[:1] return kwargs def parse_bits(parser, bits, params, varargs, varkw, defaults, takes_context, name): """ Parses bits for template tag helpers (simple_tag, include_tag and assignment_tag), in particular by detecting syntax errors and by extracting positional and keyword arguments. """ if takes_context: if params[0] == 'context': params = params[1:] else: raise TemplateSyntaxError( "'%s' is decorated with takes_context=True so it must " "have a first argument of 'context'" % name) args = [] kwargs = {} unhandled_params = list(params) for bit in bits: # First we try to extract a potential kwarg from the bit kwarg = token_kwargs([bit], parser) if kwarg: # The kwarg was successfully extracted param, value = kwarg.items()[0] if param not in params and varkw is None: # An unexpected keyword argument was supplied raise TemplateSyntaxError( "'%s' received unexpected keyword argument '%s'" % (name, param)) elif param in kwargs: # The keyword argument has already been supplied once raise TemplateSyntaxError( "'%s' received multiple values for keyword argument '%s'" % (name, param)) else: # All good, record the keyword argument kwargs[str(param)] = value if param in unhandled_params: # If using the keyword syntax for a positional arg, then # consume it. unhandled_params.remove(param) else: if kwargs: raise TemplateSyntaxError( "'%s' received some positional argument(s) after some " "keyword argument(s)" % name) else: # Record the positional argument args.append(parser.compile_filter(bit)) try: # Consume from the list of expected positional arguments unhandled_params.pop(0) except IndexError: if varargs is None: raise TemplateSyntaxError( "'%s' received too many positional arguments" % name) if defaults is not None: # Consider the last n params handled, where n is the # number of defaults. unhandled_params = unhandled_params[:-len(defaults)] if unhandled_params: # Some positional arguments were not supplied raise TemplateSyntaxError( u"'%s' did not receive value(s) for the argument(s): %s" % (name, u", ".join([u"'%s'" % p for p in unhandled_params]))) return args, kwargs class TagHelperNode(Node): """ Base class for tag helper nodes such as SimpleNode, InclusionNode and AssignmentNode. Manages the positional and keyword arguments to be passed to the decorated function. """ def __init__(self, takes_context, args, kwargs): self.takes_context = takes_context self.args = args self.kwargs = kwargs def get_resolved_arguments(self, context): resolved_args = [var.resolve(context) for var in self.args] if self.takes_context: resolved_args = [context] + resolved_args resolved_kwargs = dict((k, v.resolve(context)) for k, v in self.kwargs.items()) return resolved_args, resolved_kwargs def assignment_tag(self, func=None, takes_context=None, name=None): def dec(func): params, varargs, varkw, defaults = getargspec(func) class AssignmentNode(TagHelperNode): def __init__(self, takes_context, args, kwargs, target_var): super(AssignmentNode, self).__init__(takes_context, args, kwargs) self.target_var = target_var def render(self, context): resolved_args, resolved_kwargs = self.get_resolved_arguments(context) context[self.target_var] = func(*resolved_args, **resolved_kwargs) return '' function_name = (name or getattr(func, '_decorated_function', func).__name__) def compile_func(parser, token): bits = token.split_contents()[1:] if len(bits) < 2 or bits[-2] != 'as': raise TemplateSyntaxError( "'%s' tag takes at least 2 arguments and the " "second last argument must be 'as'" % function_name) target_var = bits[-1] bits = bits[:-2] args, kwargs = parse_bits(parser, bits, params, varargs, varkw, defaults, takes_context, function_name) return AssignmentNode(takes_context, args, kwargs, target_var) compile_func.__doc__ = func.__doc__ self.tag(function_name, compile_func) return func if func is None: # @register.assignment_tag(...) return dec elif callable(func): # @register.assignment_tag return dec(func) else: raise TemplateSyntaxError("Invalid arguments provided to assignment_tag") Library.assignment_tag = assignment_tag