[5.8] Add setDriver()

[stancl]

I'd like to change the Redis driver at runtime (in tests, to verify that a part of my package works both with predis and phpredis). I'm unable to do that because RedisManager seems to be a singleton whose driver property can't be changed.

>>> use Illuminate\Support\Facades\Redis;
>>> config('database.redis.client');
=> "phpredis"
>>> Redis::resolve('default');
=> Illuminate\Redis\Connections\PhpRedisConnection {#3062}
>>> config(['database.redis.client' => 'predis']);
=> null
>>> config('database.redis.client');
=> "predis"
>>> Redis::resolve('default');
=> Illuminate\Redis\Connections\PhpRedisConnection {#3058}

Changing the driver property on RedisManager should allow to switch the connection driver. All methods for resolving connections use the connector() method which returns a connector instance based on the value of the driver property:

framework/src/Illuminate/Redis/RedisManager.php

Lines 147 to 160 in 74b4267

	/**
	* Get the connector instance for the current driver.
	*
	* @return \Illuminate\Redis\Connectors\PhpRedisConnector|\Illuminate\Redis\Connectors\PredisConnector
	*/
	protected function connector()
	{
	switch ($this->driver) {
	case 'predis':
	return new Connectors\PredisConnector;
	case 'phpredis':
	return new Connectors\PhpRedisConnector;
	}
	}

I see that changing the Redis driver at runtime doesn't have much use in application code, unlike the database, because you can have multiple connections. However, it's impossible to test predis and phpredis support without this feature. If you don't want a setter, changing the visibility of the driver property to a public would work as well.