Switch from class_uses() to duck test for File::setModel() #4748

Co-Authored-By: Nico Hoffmann  ෴. <3788865+distantnative@users.noreply.github.com>
Co-Authored-By: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-Authored-By: Lukas Bestle <1595007+lukasbestle@users.noreply.github.com>

src/Filesystem/File.php

@@ -444,7 +444,7 @@ public function root(): string|null
 	 */
 	protected function setModel(object|null $model = null): static
 	{
-		if ($model !== null && in_array(IsFile::class, class_uses($model)) !== true) {
+		if ($model !== null && method_exists($model, 'hasIsFileTrait') !== true) {
 			throw new InvalidArgumentException('The model object must use the "Kirby\Filesystem\IsFile" trait');
 		}
 

src/Filesystem/IsFile.php

@@ -109,6 +109,16 @@ public function exists(): bool
 		return file_exists($this->root()) === true;
 	}
 
+	/**
+	 * To check the existence of the IsFile trait
+	 *
+	 * @todo Switch to class constant in traits when min PHP version 8.2 required
+	 * @codeCoverageIgnore
+	 */
+	protected function hasIsFileTrait(): bool
+	{
+		return true;
+	}
 
 	/**
 	 * Returns the app instance

tests/Filesystem/FileTest.php

@@ -8,6 +8,11 @@
 
 require_once __DIR__ . '/mocks.php';
 
+class InvalidFileModel
+{
+	public string $foo = 'bar';
+}
+
 /**
  * @coversDefaultClass \Kirby\Filesystem\File
  */
@@ -462,7 +467,7 @@ public function testInvalidModel()
 
 		new File([
 			'root' => $this->fixtures . '/test.js',
-			'model' => Page::factory(['slug' => 'test'])
+			'model' => new InvalidFileModel()
 		]);
 	}