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Deprecate IMPERIAL_SYSTEM unit system and linked constants and properties

· One min read

As of Home Assistant Core 2022.11, the IMPERIAL_SYSTEM is deprecated, replaced by US_CUSTOMARY_SYSTEM. The is_metric and name properties of a unit system are likewise deprecated and should not be used.

Custom integrations referencing this unit system or these properties will need to be adjusted to use instance checks instead.


if hass.config.units is METRIC_SYSTEM:

if hass.config.units is US_CUSTOMARY_SYSTEM:

To avoid confusion with future unit systems, the constants CONF_UNIT_SYSTEM_IMPERIAL and CONF_UNIT_SYSTEM_METRIC are also deprecated and should no longer be referenced:

  • if they were used to compare against the name of a unit system, then this is no longer needed.
  • if they were used for another reason, then local constants should be created instead.