fix(testing): preserve raw path in TestClient methods (#2159)

* fix TestClient to preserve raw URI

* add test and changelog

docs/_newsfragments/2157.bugfix.rst

@@ -0,0 +1 @@
+:class:`~falcon.testing.TestCase` mimics behavior of real WSGI servers following WSGI spec where is said that ``PATH_INFO`` CGI variable for WSGI app is already percent-decoded. However, this breaks routing if slash (encoded as ``%2F``) is part of path element, not a path separator, as explained in the FAQ :ref:`routing_encoded_slashes`. The workaround based on some WSGI servers' non-standard CGI variables described in :ref:`raw_url_path_recipe` recipe breaks tests because :py:func:`falcon.testing.helpers.create_environ` hard-code CGI variable ``RAW_URI`` to ``/`` instead to real path *before* percent-decoding.

falcon/testing/helpers.py

@@ -1151,7 +1151,8 @@ def create_environ(
     body = io.BytesIO(body.encode() if isinstance(body, str) else body)
 
     # NOTE(kgriffs): wsgiref, gunicorn, and uWSGI all unescape
-    # the paths before setting PATH_INFO
+    # the paths before setting PATH_INFO but preserve raw original
+    raw_path = path
     path = uri.decode(path, unquote_plus=False)
 
     # NOTE(kgriffs): The decoded path may contain UTF-8 characters.
@@ -1194,7 +1195,7 @@ def create_environ(
         'PATH_INFO': path,
         'QUERY_STRING': query_string,
         'REMOTE_PORT': '65133',
-        'RAW_URI': '/',
+        'RAW_URI': raw_path,
         'SERVER_NAME': host,
         'SERVER_PORT': port,
         'wsgi.version': (1, 0),

tests/test_testing.py

@@ -164,6 +164,13 @@ def test_create_environ_default_ua_override():
     assert req.user_agent == ua
 
 
+def test_create_environ_preserve_raw_uri():
+    uri = '/cache/http%3A%2F%2Ffalconframework.org/status'
+    environ = testing.create_environ(path=uri)
+    assert environ['PATH_INFO'] == '/cache/http://falconframework.org/status'
+    assert environ['RAW_URI'] == uri
+
+
 def test_missing_header_is_none():
     req = testing.create_req()
     assert req.auth is None