diff --git a/tests/phpunit/tests/media.php b/tests/phpunit/tests/media.php
index 06b8cdb59a..0e8870f6b6 100644
--- a/tests/phpunit/tests/media.php
+++ b/tests/phpunit/tests/media.php
@@ -1430,7 +1430,7 @@ EOF;
 	}
 
 	/**
-	 * Helper function to get image size array from size "name"
+	 * Helper function to get image size array from size "name".
 	 */
 	function _get_image_size_array_from_meta( $image_meta, $size_name ) {
 		$array = false;
@@ -1443,6 +1443,10 @@ EOF;
 			}
 		}
 
+		if ( ! $array ) {
+			$this->fail( sprintf( "Could not retrieve image metadata for size '%s'.", $size_name ) );
+		}
+
 		return $array;
 	}