fix: Restore 3.1.x-compatible Redis counters and reads. Follow-up to #82.

system/core/CodeIgniter.php

@@ -56,7 +56,7 @@
  * @var	string
  *
  */
-	const CI_VERSION = '3.4.6';
+	const CI_VERSION = '3.4.7';
 
 /*
  * ------------------------------------------------------

system/libraries/Cache/drivers/Cache_redis.php

@@ -162,18 +162,12 @@ public function __construct()
 	public function get($key)
 	{
 		$data = $this->_redis->hMGet($key, array('__ci_type', '__ci_value'));
-		// Also serves scalars that 3.1.x cached as plain strings
+
 		if ($data === FALSE)
 		{
 			return $this->_get_v31($key);
 		}
 
-		// Key doesn't exist (hMGet returns an array of FALSE values)
-		if ( ! isset($data['__ci_type'], $data['__ci_value']) OR $data['__ci_value'] === FALSE)
-		{
-			return FALSE;
-		}
-
 		switch ($data['__ci_type'])
 		{
 			case 'array':
@@ -295,15 +289,14 @@ public function decrement($id, $offset = 1)
 	 */
 	protected function _increment($id, $offset)
 	{
-		// Also serves scalars that 3.1.x cached as plain strings, incrBy creates the key if not existing
-		if ($this->_redis->type($id) === Redis::REDIS_STRING)
+		$value = $this->_redis->incrBy($id, $offset);
+
+		if ($value === FALSE)
 		{
-			return $this->_redis->incrBy($id, $offset);
+			$value = $this->_redis->hIncrBy($id, '__ci_value', $offset);
+			$value === FALSE OR $this->_redis->hSet($id, '__ci_type', 'integer');
 		}
 
-		$value = $this->_redis->hIncrBy($id, '__ci_value', $offset);
-		$value === FALSE OR $this->_redis->hSet($id, '__ci_type', 'integer');
-
 		return $value;
 	}
 
@@ -391,16 +384,16 @@ public function __destruct()
 	// ------------------------------------------------------------------------
 
 	/**
-	 * Get scalars that 3.1.x cached as plain strings
+	 * Get a value stored as a Redis string: a counter from increment() or a value cached by 3.1.x
 	 *
 	 * @param	string	$key	Cache ID
 	 * @return	mixed
 	 */
-	private function _get_v31($key)
+	protected function _get_v31($key)
 	{
 		$value = $this->_redis->get($key);
 
-		if ($value !== FALSE && $this->_redis->sIsMember('_ci_redis_serialized', $key))
+		if ($value !== FALSE && ! is_numeric($value) && $this->_redis->sIsMember('_ci_redis_serialized', $key))
 		{
 			return unserialize($value);
 		}

tests/codeigniter/libraries/Cache_redis_test.php

@@ -64,12 +64,35 @@ public function test_increment_non_numeric_value()
 		$this->assertSame('string', $this->redis->hashes['data']['__ci_type']);
 	}
 
+	// --------------------------------------------------------------------
+
+	public function test_get_value_cached_by_31x()
+	{
+		$this->redis->strings['plain'] = 'bar';
+		$this->redis->strings['list'] = serialize(array('a' => 1));
+		$this->redis->serialized[] = 'list';
+
+		$this->assertSame('bar', $this->cache->get('plain'));
+		$this->assertSame(array('a' => 1), $this->cache->get('list'));
+	}
+
+	// --------------------------------------------------------------------
+
+	public function test_get_counter_named_in_stale_serialized_set()
+	{
+		$this->redis->serialized[] = 'hits';
+
+		$this->assertSame(5, $this->cache->increment('hits', 5));
+		$this->assertEquals(5, $this->cache->get('hits'));
+	}
+
 }
 
 class Cache_redis_server_stub {
 
 	public $strings = array();
 	public $hashes = array();
+	public $serialized = array();
 
 	public function incrBy($key, $offset)
 	{
@@ -134,7 +157,7 @@ public function get($key)
 
 	public function sIsMember($key, $member)
 	{
-		return FALSE;
+		return $key === '_ci_redis_serialized' && in_array($member, $this->serialized, TRUE);
 	}
 
 	public function close()