54 files declare their use of FacetInterface in Facets 8

ArrayWidget.php in src/Plugin/facets/widget/ArrayWidget.php

BooleanItemProcessor.php in src/Plugin/facets/processor/BooleanItemProcessor.php

BuildProcessorInterface.php in src/Processor/BuildProcessorInterface.php

CountLimitProcessor.php in src/Plugin/facets/processor/CountLimitProcessor.php

CustomWidget.php in tests/facets_custom_widget/src/Plugin/facets/widget/CustomWidget.php

DateItemProcessor.php in src/Plugin/facets/processor/DateItemProcessor.php

DefaultFacetManager.php in src/FacetManager/DefaultFacetManager.php

DependentFacetProcessor.php in src/Plugin/facets/processor/DependentFacetProcessor.php

DropdownWidget.php in src/Plugin/facets/widget/DropdownWidget.php

ExcludeSpecifiedItemsProcessor.php in src/Plugin/facets/processor/ExcludeSpecifiedItemsProcessor.php

Facet.php in src/Entity/Facet.php

FacetController.php in src/Controller/FacetController.php

facets.module in ./facets.module

Contains facets.module.

FacetSettingsForm.php in src/Form/FacetSettingsForm.php

FacetSourcePluginInterface.php in src/FacetSource/FacetSourcePluginInterface.php

GranularItemProcessor.php in src/Plugin/facets/processor/GranularItemProcessor.php

HideActiveItemsProcessor.php in src/Plugin/facets/processor/HideActiveItemsProcessor.php

HideNonNarrowingResultProcessor.php in src/Plugin/facets/processor/HideNonNarrowingResultProcessor.php

HideOnlyOneItemProcessor.php in src/Plugin/facets/processor/HideOnlyOneItemProcessor.php

InvalidQT.php in tests/facets_custom_widget/src/Plugin/facets/processor/InvalidQT.php

LinksWidget.php in src/Plugin/facets/widget/LinksWidget.php

ListItemProcessor.php in src/Plugin/facets/processor/ListItemProcessor.php

PostQueryProcessorInterface.php in src/Processor/PostQueryProcessorInterface.php

PreQueryProcessorInterface.php in src/Processor/PreQueryProcessorInterface.php

ProcessorInterface.php in src/Processor/ProcessorInterface.php

ProcessorPluginBase.php in src/Processor/ProcessorPluginBase.php

QueryString.php in src/Plugin/facets/url_processor/QueryString.php

QueryStringCreated.php in src/Event/QueryStringCreated.php

RangeSliderProcessor.php in modules/facets_range_widget/src/Plugin/facets/processor/RangeSliderProcessor.php

RangeSliderWidget.php in modules/facets_range_widget/src/Plugin/facets/widget/RangeSliderWidget.php

Result.php in src/Result/Result.php

SearchApiBaseFacetSource.php in src/Plugin/facets/facet_source/SearchApiBaseFacetSource.php

SearchApiDateTest.php in tests/src/Kernel/Plugin/query_type/SearchApiDateTest.php

SearchApiDisplay.php in src/Plugin/facets/facet_source/SearchApiDisplay.php

SearchApiGranularTest.php in tests/src/Unit/Plugin/query_type/SearchApiGranularTest.php

SearchApiStringTest.php in tests/src/Unit/Plugin/query_type/SearchApiStringTest.php

ShowOnlyDeepestLevelItemsProcessor.php in src/Plugin/facets/processor/ShowOnlyDeepestLevelItemsProcessor.php

ShowSiblingsProcessor.php in src/Plugin/facets/processor/ShowSiblingsProcessor.php

SliderProcessor.php in modules/facets_range_widget/src/Plugin/facets/processor/SliderProcessor.php

SliderWidget.php in modules/facets_range_widget/src/Plugin/facets/widget/SliderWidget.php

SortProcessorPluginBase.php in src/Processor/SortProcessorPluginBase.php

TermWeightWidgetOrderProcessor.php in src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php

TestPreQuery.php in tests/facets_custom_widget/src/Plugin/facets/processor/TestPreQuery.php

TranslateEntityAggregatedFieldProcessor.php in src/Plugin/facets/processor/TranslateEntityAggregatedFieldProcessor.php

TranslateEntityProcessor.php in src/Plugin/facets/processor/TranslateEntityProcessor.php

TranslateEntityProcessorTest.php in tests/src/Unit/Plugin/processor/TranslateEntityProcessorTest.php

UidToUserNameCallbackProcessor.php in src/Plugin/facets/processor/UidToUserNameCallbackProcessor.php

UrlIntegrationTest.php in tests/src/Functional/UrlIntegrationTest.php

UrlProcessorHandler.php in src/Plugin/facets/processor/UrlProcessorHandler.php

UrlProcessorInterface.php in src/UrlProcessor/UrlProcessorInterface.php

UrlProcessorPluginBase.php in src/UrlProcessor/UrlProcessorPluginBase.php

WidgetPluginBase.php in src/Widget/WidgetPluginBase.php

WidgetPluginInterface.php in src/Widget/WidgetPluginInterface.php

WidgetTestBase.php in tests/src/Unit/Plugin/widget/WidgetTestBase.php