Commit 7e1376c2 authored by Baptiste Mispelon's avatar Baptiste Mispelon
Browse files

Fixed #21741 -- Fixed render_to_string to stop pushing empty dictionaries to its Context 

Thanks to kezabelle for the report and original patch
and to numerodix for his improved patch.
parent 1d3ae476

django/template/loader.py

+2 −1
Original line number Diff line number Diff line
@@ -164,13 +164,14 @@ def render_to_string(template_name, dictionary=None, context_instance=None, 
    get_template, or it may be a tuple to use select_template to find one of

    the templates in the list. Returns a string.

    """

    dictionary = dictionary or {}

    if isinstance(template_name, (list, tuple)):

        t = select_template(template_name, dirs)

    else:

        t = get_template(template_name, dirs)

    if not context_instance:

        return t.render(Context(dictionary))

    if not dictionary:

        return t.render(context_instance)

    # Add the dictionary to the context stack, ensuring it gets removed again

    # to keep the context_instance in the same state it started in.

    with context_instance.push(dictionary):

tests/template_tests/templates/test_context_stack.html

0 → 100644
+2 −0
Original line number Diff line number Diff line 
{% load custom %}

{% context_stack_length %}

tests/template_tests/templatetags/custom.py

+5 −0
Original line number Diff line number Diff line
@@ -22,6 +22,11 @@ def noop(value, param=None): 
    return value





@register.simple_tag(takes_context=True)

def context_stack_length(context):

    return len(context.dicts)





@register.simple_tag

def no_params():

    """Expected no_params __doc__"""

tests/template_tests/test_loaders.py

+12 −0
Original line number Diff line number Diff line
@@ -171,6 +171,18 @@ class RenderToStringTest(TestCase): 
            'No template names provided$',

            loader.select_template, [])



    def test_no_empty_dict_pushed_to_stack(self):

        """

        No empty dict should be pushed to the context stack when render_to_string

        is called without any argument (#21741).

        """



        # The stack should have a length of 1, corresponding to the builtins

        self.assertEqual('1',

            loader.render_to_string('test_context_stack.html').strip())

        self.assertEqual('1',

            loader.render_to_string('test_context_stack.html', context_instance=Context()).strip())





class TemplateDirsOverrideTest(unittest.TestCase):