Add support in morphTo relationship for null values (1547) (#1549)

Co-authored-by: Barry vd. Heuvel <[email protected]>

tests/Console/ModelsCommand/Morphs/Test.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\Morphs;
+
+use Barryvdh\LaravelIdeHelper\Console\ModelsCommand;
+use Barryvdh\LaravelIdeHelper\Tests\Console\ModelsCommand\AbstractModelsCommand;
+
+class Test extends AbstractModelsCommand
+{
+    public function test(): void
+    {
+        $command = $this->app->make(ModelsCommand::class);
+
+        $tester = $this->runCommand($command, [
+            '--write' => true,
+        ]);
+
+        $this->assertSame(0, $tester->getStatusCode());
+        $this->assertStringContainsString('Written new phpDocBlock to', $tester->getDisplay());
+        $this->assertMatchesMockedSnapshot();
+    }
+}