Fix AttributeError in Roborock Empty Mode entity

[allenporter]

Proposed change

Fix AttributeError in Roborock Empty Mode entity.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Roborock select entity failes with AttributeError when dust_collection_mode is None (Saros 10 dock) #159267
• This PR is related to issue:
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

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• Tests have been added to verify that the new code works.
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[home-assistant]

Hey there @Lash-L, mind taking a look at this pull request as it has been labeled with an integration (roborock) you are listed as a code owner for? Thanks!

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[Copilot]

Pull request overview

This PR fixes an AttributeError that occurs when the Roborock dust collection mode's mode attribute is None. The bug would cause a crash when trying to access .name on a None value.

Key changes:

• Updated the value_fn lambda in the dust collection mode select entity to safely handle None values using the walrus operator
• Added comprehensive test coverage for the None handling scenario with parameterized tests

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
homeassistant/components/roborock/select.py	Modified the dust_collection_mode value_fn to use walrus operator for None-safe access to mode.name, returning None when mode is None (which displays as "unknown" state)
tests/components/roborock/test_select.py	Added parameterized test test_dust_collection_mode_none to verify correct handling of None, smart, and light mode values with appropriate state expectations

[epenet]

Small tweak - I think the policy for multiline lambdas is to have the whole thing wrapped in a brackets.

Suggested change

	value_fn=lambda api: (
	mode.name if (mode := api.dust_collection_mode.mode) is not None else None # type: ignore[union-attr]
	),
	value_fn=(
	lambda api: mode.name
	if (mode := api.dust_collection_mode.mode) is not None # type: ignore[union-attr]
	else None
	),

Also
None if val is None else val
is shorter than
val if val is not None else None

[epenet]

But then again - maybe that's one for a follow-up PR as the chosen style is used accross the entity descriptions.

[epenet]

LGTM 👍