[8.x] Added class and method to create cross joined sequences for fac…

…tories (#40542)

* Added class to create matrix sequences for factories

* Fix for php7.3 support

* Rename MatrixSequence to CrossJoinSequence. Add crossJoinSequence method to Factory.

* Fix import order lint failure.

src/Illuminate/Database/Eloquent/Factories/CrossJoinSequence.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Illuminate\Database\Eloquent\Factories;
+
+use Illuminate\Support\Arr;
+
+class CrossJoinSequence extends Sequence
+{
+    /**
+     * Create a new cross join sequence instance.
+     *
+     * @param  array  $sequences
+     * @return void
+     */
+    public function __construct(...$sequences)
+    {
+        $crossJoined = array_map(
+            function ($a) {
+                return array_merge(...$a);
+            },
+            Arr::crossJoin(...$sequences),
+        );
+
+        parent::__construct(...$crossJoined);
+    }
+}

src/Illuminate/Database/Eloquent/Factories/Factory.php

@@ -491,6 +491,17 @@ public function sequence(...$sequence)
         return $this->state(new Sequence(...$sequence));
     }
 
+    /**
+     * Add a new cross joined sequenced state transformation to the model definition.
+     *
+     * @param  array  $sequence
+     * @return static
+     */
+    public function crossJoinSequence(...$sequence)
+    {
+        return $this->state(new CrossJoinSequence(...$sequence));
+    }
+
     /**
      * Define a child relationship for the model.
      *

tests/Database/DatabaseEloquentFactoryTest.php

@@ -7,6 +7,7 @@
 use Illuminate\Contracts\Foundation\Application;
 use Illuminate\Database\Capsule\Manager as DB;
 use Illuminate\Database\Eloquent\Collection;
+use Illuminate\Database\Eloquent\Factories\CrossJoinSequence;
 use Illuminate\Database\Eloquent\Factories\Factory;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Factories\Sequence;
@@ -413,6 +414,45 @@ public function test_sequences()
         $this->assertSame('index: 1', $users[1]->name);
     }
 
+    public function test_cross_join_sequences()
+    {
+        $assert = function ($users) {
+            $assertions = [
+                ['first_name' => 'Thomas', 'last_name' => 'Anderson'],
+                ['first_name' => 'Thomas', 'last_name' => 'Smith'],
+                ['first_name' => 'Agent', 'last_name' => 'Anderson'],
+                ['first_name' => 'Agent', 'last_name' => 'Smith'],
+            ];
+
+            foreach ($assertions as $key => $assertion) {
+                $this->assertSame(
+                    $assertion,
+                    $users[$key]->only('first_name', 'last_name'),
+                );
+            }
+        };
+
+        $usersByClass = FactoryTestUserFactory::times(4)
+            ->state(
+                new CrossJoinSequence(
+                    [['first_name' => 'Thomas'], ['first_name' => 'Agent']],
+                    [['last_name' => 'Anderson'], ['last_name' => 'Smith']],
+                ),
+            )
+            ->make();
+
+        $assert($usersByClass);
+
+        $usersByMethod = FactoryTestUserFactory::times(4)
+            ->crossJoinSequence(
+                [['first_name' => 'Thomas'], ['first_name' => 'Agent']],
+                [['last_name' => 'Anderson'], ['last_name' => 'Smith']],
+            )
+            ->make();
+
+        $assert($usersByMethod);
+    }
+
     public function test_resolve_nested_model_factories()
     {
         Factory::useNamespace('Factories\\');