Reduce reliance on # pragma: no cover.

Author: aaugustin

pyproject.toml

@@ -51,6 +51,7 @@ source = [
 
 [tool.coverage.report]
 exclude_lines = [
+    "except ImportError:",
     "if self.debug:",
     "pragma: no cover",
     "raise AssertionError",

src/websockets/frames.py

@@ -13,7 +13,7 @@
 
 try:
     from .speedups import apply_mask
-except ImportError:  # pragma: no cover
+except ImportError:
     from .utils import apply_mask
 
 

src/websockets/legacy/framing.py

@@ -9,7 +9,7 @@
 
 try:
     from ..speedups import apply_mask
-except ImportError:  # pragma: no cover
+except ImportError:
     from ..utils import apply_mask
 
 

src/websockets/legacy/protocol.py

@@ -714,9 +714,7 @@ async def send(
                 await self.write_frame(False, opcode, data)
 
                 # Other fragments.
-                # coverage reports this code as not covered, but it is
-                # exercised by tests - changing it breaks the tests!
-                async for fragment in aiter_message:  # pragma: no cover
+                async for fragment in aiter_message:
                     confirm_opcode, data = prepare_data(fragment)
                     if confirm_opcode != opcode:
                         raise TypeError("data contains inconsistent types")
@@ -1150,8 +1148,8 @@ async def read_data_frame(self, max_size: Optional[int]) -> Optional[Frame]:
                         if ping_id == frame.data:
                             self.latency = pong_timestamp - ping_timestamp
                             break
-                    else:  # pragma: no cover
-                        assert False, "ping_id is in self.pings"
+                    else:
+                        raise AssertionError("solicited pong not found in pings")
                     # Remove acknowledged pings from self.pings.
                     for ping_id in ping_ids:
                         del self.pings[ping_id]
@@ -1320,9 +1318,7 @@ async def close_connection(self) -> None:
             # A client should wait for a TCP close from the server.
             if self.is_client and hasattr(self, "transfer_data_task"):
                 if await self.wait_for_connection_lost():
-                    # Coverage marks this line as a partially executed branch.
-                    # I suspect a bug in coverage. Ignore it for now.
-                    return  # pragma: no cover
+                    return
                 if self.debug:
                     self.logger.debug("! timed out waiting for TCP close")
 
@@ -1340,9 +1336,7 @@ async def close_connection(self) -> None:
                     pass
 
                 if await self.wait_for_connection_lost():
-                    # Coverage marks this line as a partially executed branch.
-                    # I suspect a bug in coverage. Ignore it for now.
-                    return  # pragma: no cover
+                    return
                 if self.debug:
                     self.logger.debug("! timed out waiting for TCP close")
 
@@ -1378,9 +1372,7 @@ async def close_transport(self) -> None:
         self.transport.abort()
 
         # connection_lost() is called quickly after aborting.
-        # Coverage marks this line as a partially executed branch.
-        # I suspect a bug in coverage. Ignore it for now.
-        await self.wait_for_connection_lost()  # pragma: no cover
+        await self.wait_for_connection_lost()
 
     async def wait_for_connection_lost(self) -> bool:
         """

src/websockets/legacy/server.py

@@ -840,7 +840,7 @@ def is_serving(self) -> bool:
         """
         return self.server.is_serving()
 
-    async def start_serving(self) -> None:
+    async def start_serving(self) -> None:  # pragma: no cover
         """
         See :meth:`asyncio.Server.start_serving`.
 
@@ -852,9 +852,9 @@ async def start_serving(self) -> None:
             await server.start_serving()
 
         """
-        await self.server.start_serving()  # pragma: no cover
+        await self.server.start_serving()
 
-    async def serve_forever(self) -> None:
+    async def serve_forever(self) -> None:  # pragma: no cover
         """
         See :meth:`asyncio.Server.serve_forever`.
 
@@ -870,7 +870,7 @@ async def serve_forever(self) -> None:
         instead of exiting a :func:`serve` context.
 
         """
-        await self.server.serve_forever()  # pragma: no cover
+        await self.server.serve_forever()
 
     @property
     def sockets(self) -> Iterable[socket.socket]:
@@ -880,17 +880,17 @@ def sockets(self) -> Iterable[socket.socket]:
         """
         return self.server.sockets
 
-    async def __aenter__(self) -> WebSocketServer:
-        return self  # pragma: no cover
+    async def __aenter__(self) -> WebSocketServer:  # pragma: no cover
+        return self
 
     async def __aexit__(
         self,
         exc_type: Optional[Type[BaseException]],
         exc_value: Optional[BaseException],
         traceback: Optional[TracebackType],
-    ) -> None:
-        self.close()  # pragma: no cover
-        await self.wait_closed()  # pragma: no cover
+    ) -> None:  # pragma: no cover
+        self.close()
+        await self.wait_closed()
 
 
 class Serve:

src/websockets/sync/compatibility.py

@@ -3,7 +3,7 @@
 
 try:
     from socket import create_server as socket_create_server
-except ImportError:  # pragma: no cover
+except ImportError:
     import socket
 
     def socket_create_server(address, family=socket.AF_INET):  # type: ignore

tests/legacy/test_client_server.py

@@ -406,11 +406,11 @@ def __init__(self, *args, **kwargs):
                 self.used_for_write = False
                 super().__init__(*args, **kwargs)
 
-            def recv(self, *args, **kwargs):  # pragma: no cover
+            def recv(self, *args, **kwargs):
                 self.used_for_read = True
                 return super().recv(*args, **kwargs)
 
-            def recv_into(self, *args, **kwargs):  # pragma: no cover
+            def recv_into(self, *args, **kwargs):
                 self.used_for_read = True
                 return super().recv_into(*args, **kwargs)
 

tests/test_utils.py

@@ -82,7 +82,7 @@ def test_apply_mask_check_mask_length(self):
 
 try:
     from websockets.speedups import apply_mask as c_apply_mask
-except ImportError:  # pragma: no cover
+except ImportError:
     pass
 else: