Lazy request and response decode in CallList

respx/models.py

@@ -25,7 +25,7 @@
 from httpcore import AsyncByteStream, SyncByteStream
 
 if TYPE_CHECKING:
-    from unittest.mock import _CallList  # pragma: nocover
+    from unittest.mock import _Call, _CallList  # pragma: nocover
 
 
 URL = Tuple[bytes, bytes, Optional[int], bytes]
@@ -103,17 +103,53 @@ class Call(NamedTuple):
     response: Optional[httpx.Response]
 
 
-class CallList(list):
+class CallList:
+    def __init__(self, call_list: "_CallList"):
+        self._call_list = call_list
+
     def __iter__(self) -> Generator[Call, None, None]:
-        yield from super().__iter__()
+        for raw_call in self._call_list:
+            yield self._extract_call(raw_call)
 
-    @classmethod
-    def from_unittest_call_list(cls, call_list: "_CallList") -> "CallList":
-        return cls(Call(request, response) for (request, response), _ in call_list)
+    def __getitem__(self, item: int) -> Call:
+        raw_call = self._call_list[item]
+        return self._extract_call(raw_call)
+
+    def __len__(self) -> int:
+        return len(self._call_list)
 
     @property
     def last(self) -> Optional[Call]:
-        return self[-1] if self else None
+        return self[-1] if self._call_list else None
+
+    def set_new_call_list(self, call_list: "_CallList") -> None:
+        self._call_list = call_list
+
+    @classmethod
+    def _extract_call(cls, raw_call: "_Call") -> Call:
+        if isinstance(raw_call.decoded_call, Call):
+            return raw_call.decoded_call
+
+        request, response = raw_call[0]
+
+        decoded_call = cls._decode_call(request, response)
+        raw_call.decoded_call = decoded_call  # type: ignore
+        return decoded_call
+
+    @staticmethod
+    def _decode_call(raw_request: Request, raw_response: Response) -> Call:
+        # Decode raw request/response as HTTPX models
+        request = decode_request(raw_request)
+        response = decode_response(raw_response, request=request)
+
+        # Pre-read request/response, but only if mocked, not for pass-through streams
+        if response and not isinstance(
+            response.stream, (SyncByteStream, AsyncByteStream)
+        ):
+            request.read()
+            response.read()
+
+        return Call(request=request, response=response)
 
 
 class ResponseTemplate:
@@ -307,6 +343,7 @@ def __init__(
         self.response = response or ResponseTemplate()
         self.alias = alias
         self.stats = mock.MagicMock()
+        self.calls = CallList(self.stats.call_args_list)
 
     @property
     def called(self) -> bool:
@@ -316,10 +353,6 @@ def called(self) -> bool:
     def call_count(self) -> int:
         return self.stats.call_count
 
-    @property
-    def calls(self) -> CallList:
-        return CallList.from_unittest_call_list(self.stats.call_args_list)
-
     def get_url(self) -> Optional[URLPatternTypes]:
         return self._url
 
@@ -398,3 +431,7 @@ def match(self, request: Request) -> Optional[Union[Request, ResponseTemplate]]:
             return self.response.clone(context={"request": _request, **url_params})
 
         return None
+
+    def reset(self) -> None:
+        self.stats.reset_mock()
+        self.calls.set_new_call_list(self.stats.call_args_list)

respx/transports.py

@@ -1,4 +1,4 @@
-from typing import Any, Callable, Dict, List, Optional, Pattern, Tuple, Union, overload
+from typing import Callable, Dict, List, Optional, Pattern, Tuple, Union, overload
 from unittest import mock
 
 from httpcore import (
@@ -18,10 +18,9 @@
     HeaderTypes,
     Request,
     RequestPattern,
+    Response,
     ResponseTemplate,
     SyncResponse,
-    decode_request,
-    decode_response,
 )
 
 
@@ -40,7 +39,7 @@ def __init__(
         self.aliases: Dict[str, RequestPattern] = {}
 
         self.stats = mock.MagicMock()
-        self.calls: CallList = CallList()
+        self.calls: CallList = CallList(self.stats.call_args_list)
 
     def clear(self):
         """
@@ -53,10 +52,11 @@ def reset(self) -> None:
         """
         Resets call stats.
         """
-        self.calls.clear()
         self.stats.reset_mock()
+        self.calls.set_new_call_list(self.stats.call_args_list)
+
         for pattern in self.patterns:
-            pattern.stats.reset_mock()
+            pattern.reset()
 
     def __getitem__(self, alias: str) -> Optional[RequestPattern]:
         return self.aliases.get(alias)
@@ -271,29 +271,17 @@ def options(
 
     def record(
         self,
-        request: Any,
-        response: Optional[Any],
+        request: Request,
+        response: Optional[Response],
         pattern: Optional[RequestPattern] = None,
     ) -> None:
-        # Decode raw request/response as HTTPX models
-        request = decode_request(request)
-        response = decode_response(response, request=request)
-
         # TODO: Skip recording stats for pass_through requests?
-        # Pre-read request/response, but only if mocked, not for pass-through streams
-        if response and not isinstance(
-            response.stream, (SyncByteStream, AsyncByteStream)
-        ):
-            request.read()
-            response.read()
-
+        self.stats(request, response)
         if pattern:
             pattern.stats(request, response)
-
-        self.stats(request, response)
-
-        # Copy stats due to unwanted use of property refs in the high-level api
-        self.calls[:] = CallList.from_unittest_call_list(self.stats.call_args_list)
+            # Decoded request will be lazy written into the call object,
+            # so it should be the same object for both lists
+            pattern.stats.call_args_list[-1] = self.stats.call_args_list[-1]
 
     def assert_all_called(self) -> None:
         assert all(