Allow configuration of passthrough during BaseResponse construction

CHANGES

@@ -1,3 +1,8 @@
+0.22.0
+------
+
+* Add `passthrough` argument to `BaseResponse` object. See #557
+
 0.21.0
 ------
 

README.rst

@@ -1172,14 +1172,18 @@ need to allow an entire domain or path subtree to send requests:
     responses.add_passthru(re.compile("https://percy.io/\\w+"))
 
 
-Lastly, you can use the ``response.passthrough`` attribute on ``BaseResponse`` or
-use ``PassthroughResponse`` to enable a response to behave as a pass through.
+Lastly, you can use the ``passthrough`` argument of the ``Response`` object
+to force a response to behave as a pass through.
 
 .. code-block:: python
 
     # Enable passthrough for a single response
-    response = Response(responses.GET, "http://example.com", body="not used")
-    response.passthrough = True
+    response = Response(
+        responses.GET,
+        "http://example.com",
+        body="not used",
+        passthrough=True,
+    )
     responses.add(response)
 
     # Use PassthroughResponse

responses/__init__.py

@@ -354,6 +354,8 @@ def __init__(
         url: _URLPatternType,
         match_querystring: Union[bool, object] = None,
         match: "_MatcherIterable" = (),
+        *,
+        passthrough: bool = False,
     ) -> None:
         self.method: str = method
         # ensure the url has a default path set if the url is a string
@@ -366,6 +368,7 @@ def __init__(
 
         self.match: "_MatcherIterable" = match
         self.call_count: int = 0
+        self.passthrough = passthrough
 
     def __eq__(self, other: Any) -> bool:
         if not isinstance(other, BaseResponse):
@@ -596,7 +599,14 @@ def get_response(self, request: "PreparedRequest") -> HTTPResponse:
 
 
 class PassthroughResponse(BaseResponse):
-    passthrough: bool = True
+    def __init__(
+        self,
+        method: str,
+        url: _URLPatternType,
+        match_querystring: Union[bool, object] = None,
+        match: "_MatcherIterable" = (),
+    ):
+        super().__init__(method, url, match_querystring, match, passthrough=True)
 
 
 class OriginalResponseShim(object):

responses/tests/test_responses.py

@@ -1589,6 +1589,31 @@ def run_mocked():
     assert_reset()
 
 
+def test_passthrough_kwarg(httpserver):
+    httpserver.serve_content("OK", headers={"Content-Type": "text/plain"})
+
+    def configure_response(passthrough):
+        responses.get(httpserver.url, body="MOCK", passthrough=passthrough)
+
+    @responses.activate
+    def run_passthrough():
+        configure_response(passthrough=True)
+        resp = requests.get(httpserver.url)
+        assert_response(resp, "OK")
+
+    @responses.activate
+    def run_mocked():
+        configure_response(passthrough=False)
+        resp = requests.get(httpserver.url)
+        assert_response(resp, "MOCK")
+
+    run_mocked()
+    assert_reset()
+
+    run_passthrough()
+    assert_reset()
+
+
 def test_passthrough_response(httpserver):
     httpserver.serve_content("OK", headers={"Content-Type": "text/plain"})