Use dataclass properties in yamaha_musiccast discovery

[epenet]

Proposed change

Use dataclass properties in yamaha_musiccast discovery.

Linked to #60540

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• Dependency upgrade
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[probot-home-assistant]

Hey there @vigonotion, @micha91, mind taking a look at this pull request as it has been labeled with an integration (yamaha_musiccast) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[frenck]

Thanks, @epenet 👍

[MartinHjelmare]

Does this mean we can update the config entry host to be an empty string? Is that valid?

[epenet]

Hi @MartinHjelmare
This change was to satisfy mypy:

• urlparse reacts differently if it is passed str versus str | None
• then the generated hostname can still be None

This should be caught on line 87 though, so maybe using the form if TYPE_CHECKING twice (once for ssdp_location, and then again for hostname) would have been better?
https://github.com/epenet/home-assistant-core/blob/3b0d984959beef06a29a620815de4f3e810c73e5/homeassistant/components/yamaha_musiccast/config_flow.py#L87

I think using the standard form if discovery_info.ssdp_location is None it would have become impossible to build a test for it.

[epenet]

I can refactor as part of #60787 if needed.

[epenet]

For the discussion around urlparse, see this comment from a previous hue PR: #60598 (comment)

[MartinHjelmare]

We shouldn't accommodate bugs or write code that looks like a bug to satisfy typing. Either use if TYPE_CHECKING or some other explicit way of setting the type without allowing a potential bug to sneak in.