How I managed to encounter and recover from Computer Science's Two Hardest Problems Snippets

mistake1.php

<?php
namespace MyObject;

use Utils\ArrayUtils as _; // basically lodash

class DAO extends \Base\MySQL\DAO {
    // ...
    
    /**
     * @param int|int[] $relationAId
     * @param int|int[]|null $relationBId
     * @param int|int[]|null $relationCId
     *
     * @return MyObject|MyObject[]
     * @throws \Exception
     */
    public static function getByRelation($relationAId, $relationBId = null, $relationCId = null) {
		$result = self::getDAOCache()->getByForeignKey(MyObject::$FK_RELATION_A, $relationAId);

        if (isset($relationBId)) {
            if (empty($relationBId)) {
                return [];
            }
            $result = _::filter($result, function ($item) use ($relationBId) {
                return $item->relationBId === $relationBId;
            });
        } else if (isset($relationCId)) {
            if (empty($relationCId)) {
                return [];
            }
			$result = _::filter($result, function ($item) use ($relationCId) {
				return $item->relationCId === $relationCId;
			});
        }
        if ((!$relationBId && !$relationCId) || is_array($relationAId)) {
            return $result;
        }

        if (count($result) > 1) {
            throw new \Exception("Ambiguous object for relationA $relationAId, relationB $relationBId");
        }

        return $result;
    }
    
    // ...
}

mistake2.php

<?php
namespace MyObject;

use Utils\ArrayUtils as _; // basically lodash

class DAO extends \Base\MySQL\DAO {
    // ...
    
    /**
     * @param int|int[] $relationAId
     * @param int|int[]|null $relationBId
     * @param int|int[]|null $relationCId
     *
     * @return MyObject|MyObject[]
     * @throws \Exception
     */
    public static function getByRelation($relationAId, $relationBId = null, $relationCId = null) {
		$result = self::getDAOCache()->getByForeignKey(MyObject::$FK_RELATION_A, $relationAId);

        if (isset($relationBId)) {
            if (empty($relationBId)) {
                return [];
            }
			$relationBId = _::castArray($relationBId);
			$result = _::filter($result, function ($item) use ($relationBId) {
				return _::contains($relationBId, $item->relationBId);
			});
        } else if (isset($relationCId)) {
            if (empty($relationCId)) {
                return [];
            }
			$relationCId = _::castArray($relationCId);
			$result = _::filter($result, function ($item) use ($relationCId) {
				return _::contains($relationCId , $item->relationCId);
			});
        }
        if ((!$relationBId && !$relationCId) || is_array($relationAId)) {
            return $result;
        }

        if (count($result) > 1) {
            throw new \Exception("Ambiguous object for relationA $relationAId, relationB $relationBId");
        }

        return _::first($result);
    }
    
    // ...
}

original.php

<?php
namespace MyObject;

use Utils\ArrayUtils as _; // basically lodash

class DAO extends \Base\MySQL\DAO {
    // ...
    
    /**
     * @param int|int[] $relationAId
     * @param int|int[]|null $relationBId
     * @param int|int[]|null $relationCId
     *
     * @return MyObject|MyObject[]
     * @throws \Exception
     */
    public static function getByRelation($relationAId, $relationBId = null, $relationCId = null) {
        if (empty($relationAId)) {
            return [];
        }

        $query = self::select()->where('relationAId', $relationAId);

        if (isset($relationBId)) {
            if (empty($relationBId)) {
                return [];
            }
            $query = $query->where('relationBId', $relationBId);
        } else if (isset($relationCId)) {
            if (empty($relationCId)) {
                return [];
            }
            $query = $query->where('relationCId', $relationCId);
        }
        $result = $query->toObjects();
        if ((!$relationBId && !$relationCId) || is_array($relationAId)) {
            return $result;
        }

        if (count($result) > 1) {
            throw new \Exception("Ambiguous object for relationA $relationAId, relationB $relationBId");
        }

        return reset($result);
    }
    
    // ...
}