Everything is configured in Settings.yaml in path "Neos.ContentRepository.contentDimensions".
Inheritance: extends Neos\ContentRepository\Domain\Service\ConfigurationContentDimensionPresetSource, implements Neos\Neos\Domain\Service\ContentDimensionPresetSourceInterface
 /**
  * @test
  */
 public function findPresetByDimensionValuesWithoutExistingUriSegmentReturnsNull()
 {
     $source = new ConfigurationContentDimensionPresetSource();
     $source->setConfiguration($this->validConfiguration);
     $preset = $source->findPresetByDimensionValues('language', array('ja_JP', 'mul_ZZ'));
     $this->assertNull($preset);
 }
 /**
  *
  * @param array $allowedCombination
  * @param $allDimensionPresets
  * @return null|NodeInterface
  */
 protected function findAcceptableNode(array $allowedCombination, array $allDimensionPresets)
 {
     $pinnedDimensionName = $this->getDimension();
     foreach ($allowedCombination[$pinnedDimensionName] as $allowedPresetIdentifier) {
         $acceptableCombination = [$pinnedDimensionName => $allDimensionPresets[$pinnedDimensionName]['presets'][$allowedPresetIdentifier]['values']];
         $allowedAdditionalPresets = $this->configurationContentDimensionPresetSource->getAllowedDimensionPresetsAccordingToPreselection('country', [$pinnedDimensionName => $allowedPresetIdentifier]);
         foreach ($allowedAdditionalPresets as $allowedAdditionalDimensionName => $allowedAdditionalPreset) {
             $acceptableCombination[$allowedAdditionalDimensionName] = $allowedAdditionalPreset['presets'][$allowedAdditionalPreset['defaultPreset']]['values'];
         }
         $nodeInDimensions = $this->getNodeInDimensions($acceptableCombination, []);
         if ($nodeInDimensions !== null) {
             return $nodeInDimensions;
         }
     }
     return null;
 }