Bugfix of regex at FloatConvertor (version 2)

[i-Ching]

For passing your checks of #1942 A correct statement is: regex = r"[0-9]+(\.[0-9]+)?" Reference: https://www.flake8rules.com/rules/W605.html

I have no problem of correction without 'r' prefix directly at /site-packages/starlette/convertors.py of my computer. Having submitted last pull-request #1942, I realized to add a 'r' prefix to pass your tests.

[i-Ching]

Sorry I do not know that I deleted my fork of starlette to affect this pull request. Now I reopen it. This bugfix
regex = r"[0-9]+(\.[0-9]+)?" is for class FloatConvertor(Convertor) of site-packages/starlette/convertors.py

To avoid 500 Internal Server Error of http://localhost:8000/path/1-1 as route pattern is /path/{number:float}

[iudeen]

I checked this PR, here are my observations.

Case one: "/path/2.2" Passes 🟢

def test_router_with_float(test_client_factory):
    async def test_homepage(request):
        return JSONResponse(request.path_params)
    app = Starlette(debug=True, routes=[
        Route('/path/{number:float}', test_homepage),
    ])
    client = test_client_factory(app)
    response = client.get("/path/2.2")
    assert response.status_code == 200

Case 2: "/path/2-2" Fails 🔴

def test_router_with_float(test_client_factory):
    async def test_homepage(request):
        return JSONResponse(request.path_params)
    app = Starlette(debug=True, routes=[
        Route('/path/{number:float}', test_homepage),
    ])
    client = test_client_factory(app)
    response = client.get("/path/2-2")
    assert response.status_code == 200

This results in status code 404.

Is this intended behavior?

[Kludex]

Can you confirm that there's a 500 on the case 2 before this PR?

[iudeen]

This is in master.

self = <starlette.convertors.FloatConvertor object at 0x000001CE400C8520>
value = '2+2'

    def convert(self, value: str) -> float:
>       return float(value)
E       ValueError: could not convert string to float: '2+2'
..\starlette\convertors.py:57: ValueError

[Kludex]

Well... ValueError within the TestClient is a 500.

[iudeen]

Okay, yes, I wasn't too sure about that. So yes, before PR, Case 2 results in 500.

[iudeen]

FYR: Here is the test used: iudeen@b429651

[Kludex]

It looks like the original branch was deleted?