Added a test for SUBSTR on integer-encoded values.

test/RedisCommandsTest.php

@@ -210,8 +210,12 @@ class RedisCommandTestSuite extends PHPUnit_Framework_TestCase {
         $this->assertEquals('foo', $this->redis->substr('var', 0, 2));
         $this->assertEquals('bar', $this->redis->substr('var', 3, 5));
         $this->assertEquals('bar', $this->redis->substr('var', -3, -1));
+
         $this->assertNull($this->redis->substr('var', 5, 0));
 
+        $this->redis->set('numeric', 123456789);
+        $this->assertEquals(12345, $this->redis->substr('numeric', 0, 4));
+
         RC::testForServerException($this, RC::EXCEPTION_WRONG_TYPE, function($test) {
             $test->redis->pushTail('metavars', 'foo');
             $test->redis->substr('metavars', 0, 3);