Only render dependencies that are used of a specific page (#52)

Co-authored-by: rbeard0330 <@dul2k3BKW6m>

tests/testutils.py

@@ -1,7 +1,43 @@
-from django.test import SimpleTestCase
+from unittest.mock import Mock
+
+from django.template import Context
+from django.template.response import TemplateResponse
+from django.test import SimpleTestCase, TestCase
+
+from django_components.middleware import ComponentDependencyMiddleware
+
+# Create middleware instance
+response_stash = None
+middleware = ComponentDependencyMiddleware(get_response=lambda _: response_stash)
 
 
 class Django30CompatibleSimpleTestCase(SimpleTestCase):
     def assertHTMLEqual(self, left, right):
         left = left.replace(' type="text/javascript"', '')
         super(Django30CompatibleSimpleTestCase, self).assertHTMLEqual(left, right)
+
+    def assertInHTML(self, needle, haystack, count=None, msg_prefix=''):
+        haystack = haystack.replace(' type="text/javascript"', '')
+        super().assertInHTML(needle, haystack, count, msg_prefix)
+
+
+class Django30CompatibleTestCase(Django30CompatibleSimpleTestCase, TestCase):
+    pass
+
+
+request = Mock()
+mock_template = Mock()
+
+
+def create_and_process_template_response(template, context=None, use_middleware=True):
+    context = context if context is not None else Context({})
+    mock_template.render = lambda context, _: template.render(context)
+    response = TemplateResponse(request, mock_template, context)
+    if use_middleware:
+        response.render()
+        global response_stash
+        response_stash = response
+        response = middleware(request)
+    else:
+        response.render()
+    return response.content.decode('utf-8')