Added tests for django.template.loader.

Deprecated features aren't tested.

tests/template_loader/template_strings/template_loader/hello.html

+Hello! (template strings)

tests/template_loader/templates/template_loader/goodbye.html

+Goodbye! (Django templates)

tests/template_loader/templates/template_loader/hello.html

+Hello! (Django templates)

tests/template_loader/tests.py

+from django.test import override_settings, SimpleTestCase
+from django.template import TemplateDoesNotExist
+from django.template.loader import (
+    get_template, select_template, render_to_string)
+
+
+@override_settings(TEMPLATES=[{
+    'BACKEND': 'django.template.backends.dummy.TemplateStrings',
+    'APP_DIRS': True,
+}, {
+    'BACKEND': 'django.template.backends.django.DjangoTemplates',
+    'APP_DIRS': True,
+}])
+class TemplateLoaderTests(SimpleTestCase):
+
+    def test_get_template_first_engine(self):
+        template = get_template("template_loader/hello.html")
+        self.assertEqual(template.render(), "Hello! (template strings)\n")
+
+    def test_get_template_second_engine(self):
+        template = get_template("template_loader/goodbye.html")
+        self.assertEqual(template.render(), "Goodbye! (Django templates)\n")
+
+    def test_get_template_using_engine(self):
+        template = get_template("template_loader/hello.html", using="django")
+        self.assertEqual(template.render(), "Hello! (Django templates)\n")
+
+    def test_get_template_not_found(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            get_template("template_loader/unknown.html")
+
+    def test_select_template_first_engine(self):
+        template = select_template(["template_loader/unknown.html",
+                                    "template_loader/hello.html"])
+        self.assertEqual(template.render(), "Hello! (template strings)\n")
+
+    def test_select_template_second_engine(self):
+        template = select_template(["template_loader/unknown.html",
+                                    "template_loader/goodbye.html"])
+        self.assertEqual(template.render(), "Goodbye! (Django templates)\n")
+
+    def test_select_template_using_engine(self):
+        template = select_template(["template_loader/unknown.html",
+                                    "template_loader/hello.html"], using="django")
+        self.assertEqual(template.render(), "Hello! (Django templates)\n")
+
+    def test_select_template_empty(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            select_template([])
+
+    def test_select_template_not_found(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            select_template(["template_loader/unknown.html",
+                             "template_loader/missing.html"])
+
+    def test_select_template_tries_all_engines_before_names(self):
+        template = select_template(["template_loader/goodbye.html",
+                                    "template_loader/hello.html"])
+        self.assertEqual(template.render(), "Goodbye! (Django templates)\n")
+
+    def test_render_to_string_first_engine(self):
+        content = render_to_string("template_loader/hello.html")
+        self.assertEqual(content, "Hello! (template strings)\n")
+
+    def test_render_to_string_second_engine(self):
+        content = render_to_string("template_loader/goodbye.html")
+        self.assertEqual(content, "Goodbye! (Django templates)\n")
+
+    def test_render_to_string_using_engine(self):
+        content = render_to_string("template_loader/hello.html", using="django")
+        self.assertEqual(content, "Hello! (Django templates)\n")
+
+    def test_render_to_string_not_found(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            render_to_string("template_loader/unknown.html")
+
+    def test_render_to_string_with_list_first_engine(self):
+        content = render_to_string(["template_loader/unknown.html",
+                                    "template_loader/hello.html"])
+        self.assertEqual(content, "Hello! (template strings)\n")
+
+    def test_render_to_string_with_list_second_engine(self):
+        content = render_to_string(["template_loader/unknown.html",
+                                    "template_loader/goodbye.html"])
+        self.assertEqual(content, "Goodbye! (Django templates)\n")
+
+    def test_render_to_string_with_list_using_engine(self):
+        content = render_to_string(["template_loader/unknown.html",
+                                    "template_loader/hello.html"], using="django")
+        self.assertEqual(content, "Hello! (Django templates)\n")
+
+    def test_render_to_string_with_list_empty(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            render_to_string([])
+
+    def test_render_to_string_with_list_not_found(self):
+        with self.assertRaises(TemplateDoesNotExist):
+            render_to_string(["template_loader/unknown.html",
+                              "template_loader/missing.html"])
+
+    def test_render_to_string_with_list_tries_all_engines_before_names(self):
+        content = render_to_string(["template_loader/goodbye.html",
+                                    "template_loader/hello.html"])
+        self.assertEqual(content, "Goodbye! (Django templates)\n")