Add array conversion on creating validator

framework/yii/base/Model.php

@@ -390,7 +390,7 @@ class Model extends Component implements IteratorAggregate, ArrayAccess
 			if ($rule instanceof Validator) {
 				$validators->append($rule);
 			} elseif (is_array($rule) && isset($rule[0], $rule[1])) { // attributes, validator type
-				$validator = Validator::createValidator($rule[1], $this, $rule[0], array_slice($rule, 2));
+				$validator = Validator::createValidator($rule[1], $this, (array) $rule[0], array_slice($rule, 2));
 				$validators->append($validator);
 			} else {
 				throw new InvalidConfigException('Invalid validation rule: a rule must specify both attribute names and validator type.');

tests/unit/data/validators/models/FakedValidationModel.php

@@ -29,7 +29,7 @@ class FakedValidationModel extends Model
 	{
 		return [
 			[['val_attr_a', 'val_attr_b'], 'required', 'on' => 'reqTest'],
-			[['val_attr_c'], 'integer'],
+			['val_attr_c', 'integer'],
 		];
 	}