doctrine / orm

            $selfReferencingEntityWithoutJoinColumns = $mapping['sourceEntity'] == $mapping['targetEntity']

                && (! (isset($mapping['joinTable']['joinColumns']) || isset($mapping['joinTable']['inverseJoinColumns'])));

            if ( ! isset($mapping['joinTable']['joinColumns'])) {

                $mapping['joinTable']['joinColumns'] = [

                    [

                        'name' => $this->namingStrategy->joinKeyColumnName($mapping['sourceEntity'], $selfReferencingEntityWithoutJoinColumns ? 'source' : null),

                        'referencedColumnName' => $this->namingStrategy->referenceColumnName(),

                        'onDelete' => 'CASCADE'

                    ]

                ];

            }

            if ( ! isset($mapping['joinTable']['inverseJoinColumns'])) {

                $mapping['joinTable']['inverseJoinColumns'] = [

                ];

            }

            if ( ! isset($mapping['joinTable']['inverseJoinColumns'])) {

                $mapping['joinTable']['inverseJoinColumns'] = [

                    [

                        'name' => $this->namingStrategy->joinKeyColumnName($mapping['targetEntity'], $selfReferencingEntityWithoutJoinColumns ? 'target' : null),

                        'referencedColumnName' => $this->namingStrategy->referenceColumnName(),

                        'onDelete' => 'CASCADE'

                    ]

                ];

            }

            $mapping['joinTableColumns'] = [];