AssertionError after updating to 0.23.1

[liferthedude]

Hi!

We started getting this error after updating httpx library to 0.23.1:

AssertionError: assert self.connection is None

For now we are not sure when exactly this issue appears, in our code there are many requests being made using httpx, and some of them are executed correctly, but then it fails with the error above every time we run the script.

We have reproduced this error in both dev and production environments.

Issue disappears after rollback to httpx 0.23.0

Python 3.10.6.

full stacktrace:

  File "<project_root>/env/lib/python3.10/site-packages/httpx/_client.py", line 1533, in request
    return await self.send(request, auth=auth, follow_redirects=follow_redirects)
                 │    │    │             │                      └ <httpx._client.UseClientDefault object at 0x10536eb90>
                 │    │    │             └ <httpx._client.UseClientDefault object at 0x10536eb90>
                 │    │    └ <Request('POST', 'http://127.0.0.1:8001/api/post_check_result/text')>
                 │    └ <function AsyncClient.send at 0x105507ac0>
                 └ <httpx.AsyncClient object at 0x117b1e7a0>
  File "<project_root>/env/lib/python3.10/site-packages/httpx/_client.py", line 1620, in send
    response = await self._send_handling_auth(
                     │    └ <function AsyncClient._send_handling_auth at 0x105507b50>
                     └ <httpx.AsyncClient object at 0x117b1e7a0>
  File "<project_root>/env/lib/python3.10/site-packages/httpx/_client.py", line 1648, in _send_handling_auth
    response = await self._send_handling_redirects(
                     │    └ <function AsyncClient._send_handling_redirects at 0x105507be0>
                     └ <httpx.AsyncClient object at 0x117b1e7a0>
  File "<project_root>/env/lib/python3.10/site-packages/httpx/_client.py", line 1685, in _send_handling_redirects
    response = await self._send_single_request(request)
                     │    │                    └ <Request('POST', 'http://127.0.0.1:8001/api/post_check_result/text')>
                     │    └ <function AsyncClient._send_single_request at 0x105507c70>
                     └ <httpx.AsyncClient object at 0x117b1e7a0>
  File "<project_root>/env/lib/python3.10/site-packages/httpx/_client.py", line 1722, in _send_single_request
    response = await transport.handle_async_request(request)
                     │         │                    └ <Request('POST', 'http://127.0.0.1:8001/api/post_check_result/text')>
                     │         └ <function AsyncHTTPTransport.handle_async_request at 0x105505240>
                     └ <httpx.AsyncHTTPTransport object at 0x117b2f520>
  File "<project_root>/env/lib/python3.10/site-packages/httpx/_transports/default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
                 │    │     │                    └ <Request [b'POST']>
                 │    │     └ <function AsyncConnectionPool.handle_async_request at 0x1054e3490>
                 │    └ <httpcore.AsyncConnectionPool object at 0x117b2fa30>
                 └ <httpx.AsyncHTTPTransport object at 0x117b2f520>
  File "<project_root>/env/lib/python3.10/site-packages/httpcore/_async/connection_pool.py", line 221, in handle_async_request
    await self._attempt_to_acquire_connection(status)
          │    │                              └ <httpcore._async.connection_pool.RequestStatus object at 0x1254f9b40>
          │    └ <function AsyncConnectionPool._attempt_to_acquire_connection at 0x1054e3370>
          └ <httpcore.AsyncConnectionPool object at 0x117b2fa30>
  File "<project_root>/env/lib/python3.10/site-packages/httpcore/_async/connection_pool.py", line 160, in _attempt_to_acquire_connection
    status.set_connection(connection)
    │      │              └ <AsyncHTTPConnection ['http://127.0.0.1:8001', HTTP/1.1, IDLE, Request Count: 15]>
    │      └ <function RequestStatus.set_connection at 0x1054e3010>
    └ <httpcore._async.connection_pool.RequestStatus object at 0x1254f9b40>
  File "<project_root>/env/lib/python3.10/site-packages/httpcore/_async/connection_pool.py", line 22, in set_connection
    assert self.connection is None
           │    └ <AsyncHTTPConnection ['http://127.0.0.1:8001', HTTP/1.1, IDLE, Request Count: 15]>
           └ <httpcore._async.connection_pool.RequestStatus object at 0x1254f9b40>

AssertionError: assert self.connection is None

[Kludex]

Related encode/httpcore#580 ?