No need for "iterable_multibulk" as a default connection parameter.

Furthermore, connections that do not support certain parameters should
check and throw whether they are set, independently from their value.

lib/Predis/Connection/ConnectionParameters.php

@@ -28,7 +28,6 @@ class ConnectionParameters implements ConnectionParametersInterface
         'host' => '127.0.0.1',
         'port' => 6379,
         'timeout' => 5.0,
-        'iterable_multibulk' => false,
     );
 
     /**

lib/Predis/Connection/PhpiredisConnection.php

@@ -90,10 +90,10 @@ class PhpiredisConnection extends AbstractConnection
      */
     protected function checkParameters(ConnectionParametersInterface $parameters)
     {
-        if ($parameters->iterable_multibulk === true) {
+        if (isset($parameters->iterable_multibulk)) {
             $this->onInvalidOption('iterable_multibulk', $parameters);
         }
-        if ($parameters->persistent === true) {
+        if (isset($parameters->persistent)) {
             $this->onInvalidOption('persistent', $parameters);
         }
 

lib/Predis/Connection/PhpiredisStreamConnection.php

@@ -77,7 +77,7 @@ class PhpiredisStreamConnection extends StreamConnection
      */
     protected function checkParameters(ConnectionParametersInterface $parameters)
     {
-        if ($parameters->iterable_multibulk === true) {
+        if (isset($parameters->iterable_multibulk)) {
             $this->onInvalidOption('iterable_multibulk', $parameters);
         }
 

tests/Predis/Connection/ConnectionParametersTest.php

@@ -30,7 +30,6 @@ class ParametersTest extends StandardTestCase
         $this->assertEquals($defaults['scheme'], $parameters->scheme);
         $this->assertEquals($defaults['host'], $parameters->host);
         $this->assertEquals($defaults['port'], $parameters->port);
-        $this->assertEquals($defaults['iterable_multibulk'], $parameters->iterable_multibulk);
         $this->assertEquals($defaults['timeout'], $parameters->timeout);
     }
 
@@ -140,7 +139,6 @@ class ParametersTest extends StandardTestCase
             'host' => '127.0.0.1',
             'port' => 6379,
             'timeout' => 5.0,
-            'iterable_multibulk' => false,
         );
     }