Add state_attr_translated template filter and function

[piitaya]

Proposed change

Add state_attr_translated Jinja template function to translate entity attribute values, similar to the existing state_translated for entity states.

Attributes like fan_mode, hvac_action, preset_mode, etc. all have translations defined in strings.json under state_attributes, but these weren't accessible from templates until now.

Usage

{{ state_attr_translated("climate.living_room", "fan_mode") }}
{{ "climate.living_room" | state_attr_translated("fan_mode") }}

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 #
• This PR is related to issue:
• Link to documentation pull request: Add state_attr_translated template filter and function home-assistant.io#44028
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
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• There is no commented out code in this PR.
• I have followed the development checklist
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

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  Updated and included derived files by running: python3 -m script.hassfest.
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  Updated by running python3 -m script.gen_requirements_all.
• For the updated dependencies a diff between library versions and ideally a link to the changelog/release notes is added to the PR description.

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[Copilot]

Pull request overview

Adds a new Jinja template helper/filter, state_attr_translated, to translate entity attribute values using backend translation caches, analogous to existing state_translated for entity states.

Changes:

• Add async_translate_state_attr translation helper to resolve attribute-value translation keys (entity-specific, then domain/device-class fallbacks).
• Expose state_attr_translated as both a template global and a filter via a new StateAttrTranslated callable.
• Add unit tests covering translation helper behavior and template rendering behavior.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
homeassistant/helpers/translation.py	Adds cached-translation lookup helper for attribute values.
homeassistant/helpers/template/__init__.py	Registers new template global/filter and implements StateAttrTranslated.
tests/helpers/test_translation.py	Adds tests for the new translation helper’s key resolution / fallback behavior.
tests/helpers/template/test_init.py	Adds template-level tests for the new global/filter behavior.

[Copilot]

state_attr_translated always casts the attribute value to str before translating. If a user calls it on a non-string attribute (e.g., numeric/boolean), the return value will change type even when no translation exists, which can break template comparisons/logic. Consider only attempting translation when attr_value is a str (or Enum) and otherwise return the original attribute value unchanged; update the return type accordingly.

[piitaya]

@copilot open a new pull request to apply changes based on this feedback

[Copilot]

@piitaya I've opened a new pull request, #165320, to work on those changes. Once the pull request is ready, I'll request review from you.

[piitaya]

I'm not sure about Copilot suggestion. Should we preserve type for non-string attributes?