Relationship.php

TLDR

The Relationship.php file is part of the Illuminate\Database\Eloquent\Factories namespace and contains the Relationship class. This class is responsible for creating child relationships for parent models. It also allows specifying model instances to use when creating relationships.

Methods

__construct(Factory $factory, $relationship)

This constructor method initializes the Relationship object with a Factory instance and the name of the relationship.

createFor(Model $parent)

This method creates the child relationship for the given parent model. It checks the type of the relationship and calls the appropriate methods on the factory object.

recycle($recycle)

This method specifies the model instances to always use when creating relationships. It returns the Relationship object itself.

END

<?php

namespace Illuminate\Database\Eloquent\Factories;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsToMany;
use Illuminate\Database\Eloquent\Relations\HasOneOrMany;
use Illuminate\Database\Eloquent\Relations\MorphOneOrMany;

class Relationship
{
    /**
     * The related factory instance.
     *
     * @var \Illuminate\Database\Eloquent\Factories\Factory
     */
    protected $factory;

    /**
     * The relationship name.
     *
     * @var string
     */
    protected $relationship;

    /**
     * Create a new child relationship instance.
     *
     * @param  \Illuminate\Database\Eloquent\Factories\Factory  $factory
     * @param  string  $relationship
     * @return void
     */
    public function __construct(Factory $factory, $relationship)
    {
        $this->factory = $factory;
        $this->relationship = $relationship;
    }

    /**
     * Create the child relationship for the given parent model.
     *
     * @param  \Illuminate\Database\Eloquent\Model  $parent
     * @return void
     */
    public function createFor(Model $parent)
    {
        $relationship = $parent->{$this->relationship}();

        if ($relationship instanceof MorphOneOrMany) {
            $this->factory->state([
                $relationship->getMorphType() => $relationship->getMorphClass(),
                $relationship->getForeignKeyName() => $relationship->getParentKey(),
            ])->create([], $parent);
        } elseif ($relationship instanceof HasOneOrMany) {
            $this->factory->state([
                $relationship->getForeignKeyName() => $relationship->getParentKey(),
            ])->create([], $parent);
        } elseif ($relationship instanceof BelongsToMany) {
            $relationship->attach($this->factory->create([], $parent));
        }
    }

    /**
     * Specify the model instances to always use when creating relationships.
     *
     * @param  \Illuminate\Support\Collection  $recycle
     * @return $this
     */
    public function recycle($recycle)
    {
        $this->factory = $this->factory->recycle($recycle);

        return $this;
    }
}