feat: allow customized BooleanFieldListFilter to display with horizontal styling

[justinqian42]

Do you have any examples?

For example:

Is it a third party application feature request?

For example: No

In case of third party application, when it was updated last time?

For example: N/A

Describe your feature request

In the current filter template, line 14 checks if a filter is with the default BooleanFieldListFilter class, and if yes, apply the special horizontal styling.

However, it applies to the default BooleanFieldListFilter only. So when people like me want to customize it to display other options rather than "True" or "False" with a different class name such as "StatusBooleanFieldListFilter", it will display in the default vertical styling.

Suggesting to change it to
{% if "BooleanFieldListFilter" in spec|class_name %}
so that as long as people name the inherited filter class with string BooleanFieldListFilter in, the styling would work.

Please see the attached screenshot.

Attaching my code snippet (use case) for reference.

class StatusBooleanFieldListFilter(BooleanFieldListFilter):
    def __init__(self, field, request, params, model, model_admin, field_path):
        self.title = "Status"
        super().__init__(field, request, params, model, model_admin, field_path)

    def choices(self, changelist):
        for lookup, title in ((None, "All"), ("1", "Up"), ("0", "Down")):
            yield {
                "selected": self.lookup_val == lookup,
                "query_string": changelist.get_query_string(
                    {self.lookup_kwarg: lookup}
                ),
                "display": title,
            }

Please let me know if a PR is preferred. Happy to raise one.

Thanks in advance!