Fixed #4278 -- Added a dirs parameter to a few functions to override …

…TEMPLATE_DIRS.

* django.template.loader.get_template()
* django.template.loader.select_template()
* django.shortcuts.render()
* django.shortcuts.render_to_response()

Thanks amcnabb for the suggestion.

django/template/loader.py

@@ -130,12 +130,12 @@ def find_template(name, dirs=None):
             pass
     raise TemplateDoesNotExist(name)
 
-def get_template(template_name):
+def get_template(template_name, dirs=None):
     """
     Returns a compiled Template object for the given template name,
     handling template inheritance recursively.
     """
-    template, origin = find_template(template_name)
+    template, origin = find_template(template_name, dirs)
     if not hasattr(template, 'render'):
         # template needs to be compiled
         template = get_template_from_string(template, origin, template_name)
@@ -148,7 +148,8 @@ def get_template_from_string(source, origin=None, name=None):
     """
     return Template(source, origin, name)
 
-def render_to_string(template_name, dictionary=None, context_instance=None):
+def render_to_string(template_name, dictionary=None, context_instance=None,
+                     dirs=None):
     """
     Loads the given template_name and renders it with the given dictionary as
     context. The template_name may be a string to load a single template using
@@ -157,24 +158,24 @@ def render_to_string(template_name, dictionary=None, context_instance=None):
     """
     dictionary = dictionary or {}
     if isinstance(template_name, (list, tuple)):
-        t = select_template(template_name)
+        t = select_template(template_name, dirs)
     else:
-        t = get_template(template_name)
+        t = get_template(template_name, dirs)
     if not context_instance:
         return t.render(Context(dictionary))
     # 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):
         return t.render(context_instance)
 
-def select_template(template_name_list):
+def select_template(template_name_list, dirs=None):
     "Given a list of template names, returns the first that can be loaded."
     if not template_name_list:
         raise TemplateDoesNotExist("No template names provided")
     not_found = []
     for template_name in template_name_list:
         try:
-            return get_template(template_name)
+            return get_template(template_name, dirs)
         except TemplateDoesNotExist as e:
             if e.args[0] not in not_found:
                 not_found.append(e.args[0])

docs/ref/templates/api.txt

@@ -594,17 +594,31 @@ The Python API
 
 ``django.template.loader`` has two functions to load templates from files:
 
-.. function:: get_template(template_name)
+.. function:: get_template(template_name[, dirs])
 
     ``get_template`` returns the compiled template (a ``Template`` object) for
     the template with the given name. If the template doesn't exist, it raises
     ``django.template.TemplateDoesNotExist``.
 
-.. function:: select_template(template_name_list)
+    To override the :setting:`TEMPLATE_DIRS` setting, use the ``dirs``
+    parameter. The ``dirs`` parameter may be a tuple or list.
+
+    .. versionchanged:: 1.7
+
+       The ``dirs`` parameter was added.
+
+.. function:: select_template(template_name_list[, dirs])
 
     ``select_template`` is just like ``get_template``, except it takes a list
     of template names. Of the list, it returns the first template that exists.
 
+    To override the :setting:`TEMPLATE_DIRS` setting, use the ``dirs``
+    parameter. The ``dirs`` parameter may be a tuple or list.
+
+    .. versionchanged:: 1.7
+
+       The ``dirs`` parameter was added.
+
 For example, if you call ``get_template('story_detail.html')`` and have the
 above :setting:`TEMPLATE_DIRS` setting, here are the files Django will look for,
 in order:

docs/releases/1.7.txt

@@ -285,6 +285,14 @@ Templates
 * ``TypeError`` exceptions are not longer silenced when raised during the
   rendering of a template.
 
+* The following functions now accept a ``dirs`` parameter which is a list or
+  tuple to override :setting:`TEMPLATE_DIRS`:
+
+  * :func:`django.template.loader.get_template()`
+  * :func:`django.template.loader.select_template()`
+  * :func:`django.shortcuts.render()`
+  * :func:`django.shortcuts.render_to_response()`
+
 Tests
 ^^^^^
 

docs/topics/http/shortcuts.txt

@@ -15,7 +15,7 @@ introduce controlled coupling for convenience's sake.
 ``render``
 ==========
 
-.. function:: render(request, template_name[, dictionary][, context_instance][, content_type][, status][, current_app])
+.. function:: render(request, template_name[, dictionary][, context_instance][, content_type][, status][, current_app][, dirs])
 
    Combines a given template with a given context dictionary and returns an
    :class:`~django.http.HttpResponse` object with that rendered text.
@@ -58,6 +58,13 @@ Optional arguments
     :ref:`namespaced URL resolution strategy <topics-http-reversing-url-namespaces>`
     for more information.
 
+``dirs``
+    A tuple or list of values to override the :setting:`TEMPLATE_DIRS` setting.
+
+.. versionchanged:: 1.7
+
+   The ``dirs`` parameter was added.
+
 Example
 -------
 
@@ -83,11 +90,19 @@ This example is equivalent to::
         return HttpResponse(t.render(c),
             content_type="application/xhtml+xml")
 
+If you want to override the :setting:`TEMPLATE_DIRS` setting, use the
+``dirs`` parameter::
+
+    from django.shortcuts import render
+
+    def my_view(request):
+        # View code here...
+        return render(request, 'index.html', dirs=('custom_templates',))
 
 ``render_to_response``
 ======================
 
-.. function:: render_to_response(template_name[, dictionary][, context_instance][, content_type])
+.. function:: render_to_response(template_name[, dictionary][, context_instance][, content_type][, dirs])
 
    Renders a given template with a given context dictionary and returns an
    :class:`~django.http.HttpResponse` object with that rendered text.
@@ -125,6 +140,13 @@ Optional arguments
     The MIME type to use for the resulting document. Defaults to the value of
     the :setting:`DEFAULT_CONTENT_TYPE` setting.
 
+``dirs``
+    A tuple or list of values to override the :setting:`TEMPLATE_DIRS` setting.
+
+.. versionchanged:: 1.7
+
+   The ``dirs`` parameter was added.
+
 Example
 -------
 
@@ -150,6 +172,15 @@ This example is equivalent to::
         return HttpResponse(t.render(c),
             content_type="application/xhtml+xml")
 
+If you want to override the :setting:`TEMPLATE_DIRS` setting, use the
+``dirs`` parameter::
+
+    from django.shortcuts import render_to_response
+
+    def my_view(request):
+        # View code here...
+        return render_to_response('index.html', dirs=('custom_templates',))
+
 ``redirect``
 ============
 

tests/template_tests/other_templates/test_dirs.html

@@ -0,0 +1 @@
+spam eggs{{ obj }}

tests/template_tests/test_loaders.py

@@ -174,8 +174,28 @@ def test_empty_list(self):
                                 'No template names provided$',
                                 loader.render_to_string, [])
 
-
     def test_select_templates_from_empty_list(self):
         six.assertRaisesRegex(self, TemplateDoesNotExist,
                                 'No template names provided$',
                                 loader.select_template, [])
+
+
+class TemplateDirsOverrideTest(unittest.TestCase):
+
+    dirs_tuple = (os.path.join(os.path.dirname(upath(__file__)), 'other_templates'),)
+    dirs_list = list(dirs_tuple)
+    dirs_iter = (dirs_tuple, dirs_list)
+
+    def test_render_to_string(self):
+        for dirs in self.dirs_iter:
+            self.assertEqual(loader.render_to_string('test_dirs.html', dirs=dirs), 'spam eggs\n')
+
+    def test_get_template(self):
+        for dirs in self.dirs_iter:
+            template = loader.get_template('test_dirs.html', dirs=dirs)
+            self.assertEqual(template.render(Context({})), 'spam eggs\n')
+
+    def test_select_template(self):
+        for dirs in self.dirs_iter:
+            template = loader.select_template(['test_dirs.html'], dirs=dirs)
+            self.assertEqual(template.render(Context({})), 'spam eggs\n')

tests/view_tests/generic_urls.py

@@ -48,10 +48,12 @@
     (r'^shortcuts/render_to_response/$', 'render_to_response_view'),
     (r'^shortcuts/render_to_response/request_context/$', 'render_to_response_view_with_request_context'),
     (r'^shortcuts/render_to_response/content_type/$', 'render_to_response_view_with_content_type'),
+    (r'^shortcuts/render_to_response/dirs/$', 'render_to_response_view_with_dirs'),
     (r'^shortcuts/render/$', 'render_view'),
     (r'^shortcuts/render/base_context/$', 'render_view_with_base_context'),
     (r'^shortcuts/render/content_type/$', 'render_view_with_content_type'),
     (r'^shortcuts/render/status/$', 'render_view_with_status'),
     (r'^shortcuts/render/current_app/$', 'render_view_with_current_app'),
+    (r'^shortcuts/render/dirs/$', 'render_with_dirs'),
     (r'^shortcuts/render/current_app_conflict/$', 'render_view_with_current_app_conflict'),
 )

tests/view_tests/other_templates/render_dirs_test.html

@@ -0,0 +1 @@
+spam eggs

tests/view_tests/tests/test_shortcuts.py

@@ -27,6 +27,12 @@ def test_render_to_response_with_content_type(self):
         self.assertEqual(response.content, b'FOO.BAR..\n')
         self.assertEqual(response['Content-Type'], 'application/x-rendertest')
 
+    def test_render_to_response_with_dirs(self):
+        response = self.client.get('/shortcuts/render_to_response/dirs/')
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response.content, b'spam eggs\n')
+        self.assertEqual(response['Content-Type'], 'text/html; charset=utf-8')
+
     def test_render(self):
         response = self.client.get('/shortcuts/render/')
         self.assertEqual(response.status_code, 200)
@@ -55,5 +61,11 @@ def test_render_with_current_app(self):
         response = self.client.get('/shortcuts/render/current_app/')
         self.assertEqual(response.context.current_app, "foobar_app")
 
+    def test_render_with_dirs(self):
+        response = self.client.get('/shortcuts/render/dirs/')
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response.content, b'spam eggs\n')
+        self.assertEqual(response['Content-Type'], 'text/html; charset=utf-8')
+
     def test_render_with_current_app_conflict(self):
         self.assertRaises(ValueError, self.client.get, '/shortcuts/render/current_app_conflict/')

tests/view_tests/views.py

@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+import os
 import sys
 
 from django.core.exceptions import PermissionDenied, SuspiciousOperation
@@ -10,10 +11,12 @@
 from django.views.debug import technical_500_response, SafeExceptionReporterFilter
 from django.views.decorators.debug import (sensitive_post_parameters,
                                            sensitive_variables)
+from django.utils._os import upath
 from django.utils.log import getLogger
 
 from . import BrokenException, except_args
 
+dirs = (os.path.join(os.path.dirname(upath(__file__)), 'other_templates'),)
 
 
 def index_page(request):
@@ -85,6 +88,9 @@ def render_to_response_view_with_content_type(request):
         'bar': 'BAR',
     }, content_type='application/x-rendertest')
 
+def render_to_response_view_with_dirs(request):
+    return render_to_response('render_dirs_test.html', dirs=dirs)
+
 def render_view(request):
     return render(request, 'debug/render_test.html', {
         'foo': 'FOO',
@@ -123,6 +129,9 @@ def render_view_with_current_app_conflict(request):
         'bar': 'BAR',
     }, current_app="foobar_app", context_instance=RequestContext(request))
 
+def render_with_dirs(request):
+    return render(request, 'render_dirs_test.html', dirs=dirs)
+
 def raises_template_does_not_exist(request, path='i_dont_exist.html'):
     # We need to inspect the HTML generated by the fancy 500 debug view but
     # the test client ignores it, so we send it explicitly.