diff --git a/tests/tests/Imagick/LayersTest.php b/tests/tests/Imagick/LayersTest.php
index 15d964d3..a5e5b4b4 100644
--- a/tests/tests/Imagick/LayersTest.php
+++ b/tests/tests/Imagick/LayersTest.php
@@ -92,6 +92,10 @@ public function testWebpFormatIsAllowedAsAnimatedFormat()
             ->method('getNumberImages')
             ->will($this->returnValue(42));
 
+        $resource->expects($this->atLeastOnce())
+            ->method('getImage')
+            ->will($this->returnValue($resource));
+
         $layers = new Layers(new Image($resource, $palette, new MetadataBag()), $palette, $resource);
 
         $layers->animate('webp', 200, 0);