esphome/tests/components/text_sensor/common.yaml

text_sensor:
  - platform: template
    name: "Test Substitute Single"
    id: test_substitute_single
    filters:
      - substitute:
          - ERROR -> Error

  - platform: template
    name: "Test Substitute Multiple"
    id: test_substitute_multiple
    filters:
      - substitute:
          - ERROR -> Error
          - WARN -> Warning
          - INFO -> Information
          - DEBUG -> Debug

  - platform: template
    name: "Test Substitute Chained"
    id: test_substitute_chained
    filters:
      - substitute:
          - foo -> bar
      - to_upper
      - substitute:
          - BAR -> baz

  - platform: template
    name: "Test Map Single"
    id: test_map_single
    filters:
      - map:
          - ON -> Active

  - platform: template
    name: "Test Map Multiple"
    id: test_map_multiple
    filters:
      - map:
          - ON -> Active
          - OFF -> Inactive
          - UNKNOWN -> Error
          - IDLE -> Standby

  - platform: template
    name: "Test Map Passthrough"
    id: test_map_passthrough
    filters:
      - map:
          - Good -> Excellent
          - Bad -> Poor

  - platform: template
    name: "Test All Filters"
    id: test_all_filters
    filters:
      - to_upper
      - to_lower
      - append: " suffix"
      - prepend: "prefix "
      - substitute:
          - prefix -> PREFIX
          - suffix -> SUFFIX
      - map:
          - PREFIX text SUFFIX -> mapped