Template filters now pass numerical arguments through as numbers.

This was the (undocumented) behaviour prior to r10118 and now it's back
again. It's neither hard nor harmful to maintain compatibility with the
old ways.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10169 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/template/__init__.py

@@ -445,34 +445,36 @@ def value(self):
             self.pointer = i
             return s
 
+# This only matches constant *strings* (things in quotes or marked for
+# translation). Numbers are treated as variables for implementation reasons
+# (so that they retain their type when passed to filters).
 constant_string = r"""
 (?:%(i18n_open)s%(strdq)s%(i18n_close)s|
 %(i18n_open)s%(strsq)s%(i18n_close)s|
 %(strdq)s|
-%(strsq)s)|
-%(num)s
+%(strsq)s)
 """ % {
     'strdq': r'"[^"\\]*(?:\\.[^"\\]*)*"', # double-quoted string
     'strsq': r"'[^'\\]*(?:\\.[^'\\]*)*'", # single-quoted string
-    'num': r'[-+\.]?\d[\d\.e]*', # numeric constant
     'i18n_open' : re.escape("_("),
     'i18n_close' : re.escape(")"),
     }
 constant_string = constant_string.replace("\n", "")
 
 filter_raw_string = r"""
 ^(?P<constant>%(constant)s)|
-^(?P<var>[%(var_chars)s]+)|
+^(?P<var>[%(var_chars)s]+|%(num)s)|
  (?:%(filter_sep)s
      (?P<filter_name>\w+)
          (?:%(arg_sep)s
              (?:
               (?P<constant_arg>%(constant)s)|
-              (?P<var_arg>[%(var_chars)s]+)
+              (?P<var_arg>[%(var_chars)s]+|%(num)s)
              )
          )?
  )""" % {
     'constant': constant_string,
+    'num': r'[-+\.]?\d[\d\.e]*',
     'var_chars': "\w\." ,
     'filter_sep': re.escape(FILTER_SEPARATOR),
     'arg_sep': re.escape(FILTER_ARGUMENT_SEPARATOR),

tests/regressiontests/templates/custom.py

@@ -0,0 +1,11 @@
+from django import test
+from django import template
+
+
+custom_filters = """
+>>> t = template.Template("{% load custom %}{{ string|trim:5 }}")
+>>> ctxt = template.Context({"string": "abcdefghijklmnopqrstuvwxyz"})
+>>> t.render(ctxt)
+u"abcde"
+"""
+

tests/regressiontests/templates/templatetags/custom.py

@@ -0,0 +1,11 @@
+from django import template
+from django.template.defaultfilters import stringfilter
+
+register = template.Library()
+
+def trim(value, num):
+    return value[:num]
+trim = stringfilter(trim)
+
+register.filter(trim)
+

tests/regressiontests/templates/tests.py

@@ -18,9 +18,10 @@
 from django.utils.safestring import mark_safe
 from django.utils.tzinfo import LocalTimezone
 
-from unicode import unicode_tests
 from context import context_tests
+from custom import custom_filters
 from parser import filter_parsing, variable_parsing
+from unicode import unicode_tests
 
 try:
     from loaders import *
@@ -34,6 +35,7 @@
     'unicode': unicode_tests,
     'context': context_tests,
     'filter_parsing': filter_parsing,
+    'custom_filters': custom_filters,
 }
 
 #################################