public function testPrefixForTable()
{
$redis = M::mock(Redis::class);
// schema version
$redis->shouldReceive('get')->with('2d23e940e190c4fefe3955fe8cf5c8a8')->andReturn(1);
// update version
$redis->shouldReceive('get')->with('1031d621441d2f689f95870d86225cf2')->andReturn(6);
$meta = new RedisMeta($redis);
$prefix = $meta->prefix('angejia', 'user', true);
$this->assertEquals('pea:angejia:user:1:6', $prefix);
}