TypeError

[SergeyPotekhin]

Checklist

• The bug is reproducible against the latest release or master.
• There are no similar issues or pull requests to fix it yet.

Describe the bug

uvicorn --host 0.0.0.0 --port 9000 app:app
INFO: Started server process [71014]
INFO: Waiting for application startup.
INFO: Application startup complete.
INFO: Uvicorn running on http://0.0.0.0:9000 (Press CTRL+C to quit)
INFO: 127.0.0.1:58114 - "GET / HTTP/1.1" 500 Internal Server Error
ERROR: Exception in ASGI application
Traceback (most recent call last):
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/uvicorn/protocols/http/h11_impl.py", line 364, in run_asgi
result = await app(self.scope, self.receive, self.send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/uvicorn/middleware/proxy_headers.py", line 75, in call
return await self.app(scope, receive, send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/fastapi/applications.py", line 212, in call
await super().call(scope, receive, send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/applications.py", line 119, in call
await self.middleware_stack(scope, receive, send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/middleware/errors.py", line 181, in call
raise exc
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/middleware/errors.py", line 159, in call
await self.app(scope, receive, _send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/exceptions.py", line 87, in call
raise exc
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/exceptions.py", line 76, in call
await self.app(scope, receive, sender)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/routing.py", line 659, in call
await route.handle(scope, receive, send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/routing.py", line 259, in handle
await self.app(scope, receive, send)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/routing.py", line 61, in app
response = await func(request)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/fastapi/routing.py", line 216, in app
solved_result = await solve_dependencies(
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/fastapi/dependencies/utils.py", line 465, in solve_dependencies
response = response or Response(
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/responses.py", line 50, in init
self.init_headers(headers)
File "/home/rds/venvs/new_deploy_test/venv/lib/python3.10/site-packages/starlette/responses.py", line 77, in init_headers
and not (self.status_code < 200 or self.status_code in (204, 304))
TypeError: '<' not supported between instances of 'NoneType' and 'int'

Steps to reproduce the bug

Python 3.10
Code app.py:

from fastapi import FastAPI
from fastapi.responses import JSONResponse

app = FastAPI()

@app.get("/")
async def read_root():
    return JSONResponse(status_code=200, content={"Success":"Ok!"})

uvicorn --host 0.0.0.0 --port 9000 app:app

Expected behavior

No response

Actual behavior

No response

Debugging material

No response

Environment

Linux Manjaro
Python 3.10.2 (main, Jan 15 2022, 19:56:27) [GCC 11.1.0] on linux
starlette 0.18.0

Additional context

No response

[Kludex]

FastAPI doesn't support Starlette 0.18.0.

Use/see tiangolo/fastapi#4483 .