Issue #2909262 by borisson_: Limit taxonomy weight processor to entity reference fields, add a test

src/Plugin/facets/processor/TermWeightWidgetOrderProcessor.php

@@ -4,6 +4,9 @@ namespace Drupal\facets\Plugin\facets\processor;
 
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\TypedData\ComplexDataDefinitionInterface;
+use Drupal\Core\TypedData\DataReferenceDefinitionInterface;
+use Drupal\facets\FacetInterface;
 use Drupal\facets\Processor\SortProcessorPluginBase;
 use Drupal\facets\Result\Result;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -86,4 +89,29 @@ class TermWeightWidgetOrderProcessor extends SortProcessorPluginBase implements
     return ($term_a->getWeight() < $term_b->getWeight()) ? -1 : 1;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function supportsFacet(FacetInterface $facet) {
+    $data_definition = $facet->getDataDefinition();
+    if ($data_definition->getDataType() === 'entity_reference') {
+      return TRUE;
+    }
+    if (!($data_definition instanceof ComplexDataDefinitionInterface)) {
+      return FALSE;
+    }
+
+    $data_definition = $facet->getDataDefinition();
+    $property_definitions = $data_definition->getPropertyDefinitions();
+    foreach ($property_definitions as $definition) {
+      if ($definition instanceof DataReferenceDefinitionInterface
+        && $definition->getDataType() === 'entity_reference'
+        && $definition->getConstraint('EntityType') === 'taxonomy_term'
+      ) {
+        return TRUE;
+      }
+    }
+    return FALSE;
+  }
+
 }

tests/src/Functional/HierarchicalFacetIntegrationTest.php

@@ -203,6 +203,35 @@ class HierarchicalFacetIntegrationTest extends FacetsTestBase {
     $this->assertStringPosition('Child 2', 'Child 1');
   }
 
+  /**
+   * Tests sorting by weight of a taxonomy term.
+   */
+  public function testWeightSort() {
+    $edit = [
+      'facet_settings[translate_entity][status]' => '1',
+      'facet_sorting[term_weight_widget_order][status]' => '1',
+    ];
+    $this->drupalPostForm($this->facetEditPage, $edit, 'Save');
+
+    $this->parents['Parent 1']->setWeight(15);
+    $this->parents['Parent 1']->save();
+    $this->parents['Parent 2']->setWeight(25);
+    $this->parents['Parent 2']->save();
+
+    $this->drupalGet('search-api-test-fulltext');
+    $this->assertFacetLabel('Parent 1');
+    $this->assertFacetLabel('Parent 2');
+    $this->assertStringPosition('Parent 1', 'Parent 2');
+
+    $this->parents['Parent 2']->setWeight(5);
+    $this->parents['Parent 2']->save();
+
+    $this->drupalGet('search-api-test-fulltext');
+    $this->assertFacetLabel('Parent 1');
+    $this->assertFacetLabel('Parent 2');
+    $this->assertStringPosition('Parent 2', 'Parent 1');
+  }
+
   /**
    * Verify the "Enable parent when child gets disabled" option is working.
    */

tests/src/Functional/ProcessorIntegrationTest.php

@@ -146,7 +146,7 @@ class ProcessorIntegrationTest extends FacetsTestBase {
 
     $index = $this->getIndex();
 
-    // Index the taxonomy and entity reference fields.
+    // Index a boolean field.
     $boolean_field = new Field($index, $field_name);
     $boolean_field->setType('integer');
     $boolean_field->setPropertyPath($field_name);
@@ -806,6 +806,7 @@ class ProcessorIntegrationTest extends FacetsTestBase {
     $this->assertSession()->pageTextNotContains('Boolean item label');
     $this->assertSession()->pageTextNotContains('Transform UID to user name');
     $this->assertSession()->pageTextNotContains('Transform entity ID to label');
+    $this->assertSession()->pageTextNotContains('Sort by taxonomy term weight');
   }
 
   /**
@@ -829,7 +830,12 @@ class ProcessorIntegrationTest extends FacetsTestBase {
       }
       // These processors are hidden by default, see also
       // ::testHiddenProcessors.
-      if (in_array($processor->getPluginId(), ['boolean_item', 'translate_entity', 'uid_to_username_callback'])) {
+      $hiddenProcessors = [
+        'boolean_item',
+        'translate_entity',
+        'uid_to_username_callback',
+      ];
+      if (in_array($processor->getPluginId(), $hiddenProcessors)) {
         continue;
       }