Fixed #23606 -- Implemented Client and RequestFactory trace() methods.

Thanks KevinEtienne for the suggestion.

tests/test_client/views.py

@@ -5,7 +5,10 @@ from django.core import mail
 from django.forms import fields
 from django.forms.forms import Form, ValidationError
 from django.forms.formsets import formset_factory, BaseFormSet
-from django.http import HttpResponse, HttpResponseRedirect, HttpResponseNotFound
+from django.http import (
+    HttpResponse, HttpResponseRedirect, HttpResponseNotFound,
+    HttpResponseNotAllowed, HttpResponseBadRequest,
+)
 from django.shortcuts import render_to_response
 from django.template import Context, Template
 from django.utils.decorators import method_decorator
@@ -20,6 +23,31 @@ def get_view(request):
     return HttpResponse(t.render(c))
 
 
+def trace_view(request):
+    """
+    A simple view that expects a TRACE request and echoes its status line.
+
+    TRACE requests should not have an entity; the view will return a 400 status
+    response if it is present.
+    """
+    if request.method.upper() != "TRACE":
+        return HttpResponseNotAllowed("TRACE")
+    elif request.body:
+        return HttpResponseBadRequest("TRACE requests MUST NOT include an entity")
+    else:
+        protocol = request.META["SERVER_PROTOCOL"]
+        t = Template(
+            '{{ method }} {{ uri }} {{ version }}',
+            name="TRACE Template",
+        )
+        c = Context({
+            'method': request.method,
+            'uri': request.path,
+            'version': protocol,
+        })
+        return HttpResponse(t.render(c))
+
+
 def post_view(request):
     """A view that expects a POST, and returns a different template depending
     on whether any POST data is available