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name: ha-test-harness description: Testing patterns for Home Assistant custom components—coordinator and entity unit tests, register map coverage, write-path tests, and unique_id/device stability checks. license: Complete terms in LICENSE.txt

HA Test Harness

Use when adding tests for a custom integration.

Quick start

• Unit test the coordinator (success, cached fallback, error paths, option changes).
• Validate register maps and expected entities (keys, tiers, categories).
• Test entity properties (state_class/device_class/units) and translation_key wiring.
• Write-path tests: encoding, device_id usage, no immediate refresh contention.

References

• references/coordinator-tests.md
• references/entity-tests.md
• references/write-path-tests.md
• references/registry-stability.md