Commit 7c6f2ddc authored by Curtis Maloney's avatar Curtis Maloney Committed by Tim Graham
Browse files

Simplify FilterExpression.args_check

parent 6dca603a

django/template/base.py

+7 −24
Original line number Diff line number Diff line
@@ -622,34 +622,17 @@ class FilterExpression(object): 


    def args_check(name, func, provided):

        provided = list(provided)

        plen = len(provided)

        # First argument, filter input, is implied.

        plen = len(provided) + 1

        # Check to see if a decorator is providing the real function.

        func = getattr(func, '_decorated_function', func)

        args, varargs, varkw, defaults = getargspec(func)

        # First argument is filter input.

        args.pop(0)

        if defaults:

            nondefs = args[:-len(defaults)]

        else:

            nondefs = args

        # Args without defaults must be provided.

        try:

            for arg in nondefs:

                provided.pop(0)

        except IndexError:

            # Not enough

            raise TemplateSyntaxError("%s requires %d arguments, %d provided" %

                                      (name, len(nondefs), plen))



        # Defaults can be overridden.

        defaults = list(defaults) if defaults else []

        try:

            for parg in provided:

                defaults.pop(0)

        except IndexError:

            # Too many.

        alen = len(args)

        dlen = len(defaults or [])

        # Not enough OR Too many

        if plen < (alen - dlen) or plen > alen:

            raise TemplateSyntaxError("%s requires %d arguments, %d provided" %

                                      (name, len(nondefs), plen))

                                      (name, alen - dlen, plen))



        return True

    args_check = staticmethod(args_check)

tests/template_tests/test_parser.py

+40 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ from __future__ import unicode_literals 
from unittest import TestCase



from django.template import (TokenParser, FilterExpression, Parser, Variable,

    Template, TemplateSyntaxError)

    Template, TemplateSyntaxError, Library)

from django.test.utils import override_settings

from django.utils import six
@@ -94,3 +94,42 @@ class ParserTests(TestCase): 
        with six.assertRaisesRegex(self, TemplateSyntaxError, msg) as cm:

            Template("{% if 1 %}{{ foo@bar }}{% endif %}")

        self.assertEqual(cm.exception.django_template_source[1], (10, 23))



    def test_filter_args_count(self):

        p = Parser("")

        l = Library()

        @l.filter

        def no_arguments(value):

            pass

        @l.filter

        def one_argument(value, arg):

            pass

        @l.filter

        def one_opt_argument(value, arg=False):

            pass

        @l.filter

        def two_arguments(value, arg, arg2):

            pass

        @l.filter

        def two_one_opt_arg(value, arg, arg2=False):

            pass

        p.add_library(l)

        for expr in (

                '1|no_arguments:"1"',

                '1|two_arguments',

                '1|two_arguments:"1"',

                '1|two_one_opt_arg',

            ):

            with self.assertRaises(TemplateSyntaxError):

                FilterExpression(expr, p)

        for expr in (

                # Correct number of arguments

                '1|no_arguments',

                '1|one_argument:"1"',

                # One optional

                '1|one_opt_argument',

                '1|one_opt_argument:"1"',

                # Not supplying all

                '1|two_one_opt_arg:"1"',

            ):

            FilterExpression(expr, p)