Add a test for empty HttpResponse body

Related: #210

Author: elprans

tests/http_functions/return_http_no_body/function.json

@@ -0,0 +1,16 @@
+{
+  "scriptFile": "main.py",
+  "disabled": false,
+  "bindings": [
+    {
+      "type": "httpTrigger",
+      "direction": "in",
+      "name": "req"
+    },
+    {
+      "type": "http",
+      "direction": "out",
+      "name": "$return"
+    }
+  ]
+}

tests/http_functions/return_http_no_body/main.py

@@ -0,0 +1,5 @@
+import azure.functions as azf
+
+
+def main(req: azf.HttpRequest):
+    return azf.HttpResponse()

tests/test_http_functions.py

@@ -32,6 +32,11 @@ def test_return_http_200(self):
         self.assertEqual(r.text, '<h1>Hello World™</h1>')
         self.assertEqual(r.headers['content-type'], 'text/html; charset=utf-8')
 
+    def test_return_http_no_body(self):
+        r = self.webhost.request('GET', 'return_http_no_body')
+        self.assertEqual(r.text, '')
+        self.assertEqual(r.status_code, 200)
+
     def test_return_http_auth_level_admin(self):
         r = self.webhost.request('GET', 'return_http_auth_admin',
                                  params={'code': 'testMasterKey'})