test_web test_bad_method: remove a client.getPage

Add WebErrorMixin.assertHTTPError, to replace (getPage + shouldHTTPError)

src/allmydata/test/common.py

@@ -1,6 +1,8 @@
 import os, random, struct
+import treq
 from zope.interface import implementer
 from twisted.internet import defer
+from twisted.internet.defer import inlineCallbacks, returnValue
 from twisted.internet.interfaces import IPullProducer
 from twisted.python import failure
 from twisted.application import service
@@ -509,6 +511,18 @@ class WebErrorMixin:
         d.addBoth(self._shouldHTTPError, which, _validate)
         return d
 
+    @inlineCallbacks
+    def assertHTTPError(self, url, code, response_substring,
+                        method="get", persistent=False,
+                        **args):
+        response = yield treq.request(method, url, persistent=persistent,
+                                      **args)
+        body = yield response.content()
+        self.assertEquals(response.code, code)
+        if response_substring is not None:
+            self.assertIn(response_substring, body)
+        returnValue(body)
+
 class ErrorMixin(WebErrorMixin):
     def explain_error(self, f):
         if f.check(defer.FirstError):

src/allmydata/test/web/test_web.py

@@ -4437,13 +4437,12 @@ class Web(WebMixin, WebErrorMixin, testutil.StallMixin, testutil.ReallyEqualMixi
         return d
 
 
+    @inlineCallbacks
     def test_bad_method(self):
         url = self.webish_url + self.public_url + "/foo/bar.txt"
-        d = self.shouldHTTPError("bad_method",
-                                 501, "Not Implemented",
-                                 "I don't know how to treat a BOGUS request.",
-                                 client.getPage, url, method="BOGUS")
-        return d
+        yield self.assertHTTPError(url, 501,
+                                   "I don't know how to treat a BOGUS request.",
+                                   method="BOGUS")
 
     def test_short_url(self):
         url = self.webish_url + "/uri"