Make second argument of "AbstractEnvelope" optional

The argument "parameters" which is meant to give the wrapped rule's
exception some extra information does not always need to be defined, for
example when the exception does not need any parameter.

The current version of "AbstractEnvelope" required that argument and the
rules that are extending this class are passing an empty array.

This commit will make the "parameters" argument optional. As an extra,
it will make sure the tests from the children of "AbstractEnvelope" are
also covering their parent.

Signed-off-by: Henrique Moody <henriquemoody@gmail.com>

library/Rules/AbstractEnvelope.php

@@ -42,7 +42,7 @@ abstract class AbstractEnvelope extends AbstractRule
      * @param Validatable $validatable
      * @param array $parameters
      */
-    public function __construct(Validatable $validatable, array $parameters)
+    public function __construct(Validatable $validatable, array $parameters = [])
     {
         $this->validatable = $validatable;
         $this->parameters = $parameters;

library/Rules/FilterVar.php

@@ -53,6 +53,6 @@ final class FilterVar extends AbstractEnvelope
             throw new ComponentException('Cannot accept the given filter');
         }
 
-        parent::__construct(new Callback('filter_var', $filter, $options), []);
+        parent::__construct(new Callback('filter_var', $filter, $options));
     }
 }

library/Rules/Url.php

@@ -30,6 +30,6 @@ final class Url extends AbstractEnvelope
      */
     public function __construct()
     {
-        parent::__construct(new FilterVar(FILTER_VALIDATE_URL), []);
+        parent::__construct(new FilterVar(FILTER_VALIDATE_URL));
     }
 }

tests/unit/Rules/BetweenTest.php

@@ -20,6 +20,7 @@ use Respect\Validation\Test\Stubs\CountableStub;
 /**
  * @group rule
  *
+ * @covers \Respect\Validation\Rules\AbstractEnvelope
  * @covers \Respect\Validation\Rules\Between
  */
 final class BetweenTest extends RuleTestCase

tests/unit/Rules/FilterVarTest.php

@@ -24,6 +24,7 @@ use const FILTER_VALIDATE_URL;
 /**
  * @group rule
  *
+ * @covers \Respect\Validation\Rules\AbstractEnvelope
  * @covers \Respect\Validation\Rules\FilterVar
  *
  * @author Gabriel Caruso <carusogabriel34@gmail.com>

tests/unit/Rules/LanguageCodeTest.php

@@ -19,6 +19,7 @@ use Respect\Validation\Test\RuleTestCase;
 /**
  * @group rule
  *
+ * @covers \Respect\Validation\Rules\AbstractEnvelope
  * @covers \Respect\Validation\Rules\LanguageCode
  *
  * @author Danilo Benevides <danilobenevides01@gmail.com>

tests/unit/Rules/UrlTest.php

@@ -18,6 +18,7 @@ use Respect\Validation\Test\RuleTestCase;
 /**
  * @group rule
  *
+ * @covers \Respect\Validation\Rules\AbstractEnvelope
  * @covers \Respect\Validation\Rules\Url
  *
  * @author Gabriel Caruso <carusogabriel34@gmail.com>