URL encoding for request params in version 0.28.1

[ajjajjajjajj]

I'm encountering the following when using the OData $filter keyword as part of my GET request params:

On httpx version 0.27.2, I was able to make get requests (using Client.request()) with an OData filter with the following:

import httpx
url = "..."
with httpx.Client() as client:
    response = client.request(
        "get",
        link,
        params={
            "$filter": "createdAt gt 2025-06-11T07:46:35.713000+00:00",
        },
        headers=headers,
    )

if response.status_code == 200:
    print(response.json()) # succeeds with version 0.27.2
else:
    print(f"Failed to fetch data: {response.status_code}, {response.text}") # fails with 0.28.1

When upgraded to version 0.28.1, it seems that the URL fails to encode correctly (spaces replaced with "+" rather than "%20"):

INFO:httpx:HTTP Request: GET <url>?%24filter=createdAt+gt+2025-06-11T07%3A46%3A35.713000%2B00%3A00 "HTTP/1.1 400 Bad Request"
Failed to fetch data: 400, {"error":{"code":"400","message":"Parsing URL failed at position 166: Expected \"(\", \"/\", a whitespace, or an optional whitespace but \"+\" found."}}

Any advice on this would be appreciated!

[lovelydinosaur]

Browsers use "+" replacement for " " in query strings. It's not incorrect behaviour. (either is valid^*.)

The PR changing this is #3373... that PR is mentioned in the CHANGELOG, though isn't explicit enough about the behavior change.

^* - To be more precise here... from query inputs use the + escaping, inputs in the URL bar use the %20 style.