diff --git a/src/Client.php b/src/Client.php
index 1636cc6f..32b9b708 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -16,9 +16,9 @@ use ArrayIterator;
 use InvalidArgumentException;
 use IteratorAggregate;
 use Predis\Command\CommandInterface;
+use Predis\Command\Container\ContainerFactory;
+use Predis\Command\Container\ContainerInterface;
 use Predis\Command\RawCommand;
-use Predis\Command\Redis\Container\ContainerFactory;
-use Predis\Command\Redis\Container\ContainerInterface;
 use Predis\Command\ScriptCommand;
 use Predis\Configuration\Options;
 use Predis\Configuration\OptionsInterface;
@@ -346,29 +346,29 @@ class Client implements ClientInterface, IteratorAggregate
     }
 
     /**
-     * @param $name
+     * @param  string             $name
      * @return ContainerInterface
      */
-    public function __get($name)
+    public function __get(string $name)
     {
         return ContainerFactory::create($this, $name);
     }
 
     /**
-     * @param $name
-     * @param $value
+     * @param  string $name
+     * @param  mixed  $value
      * @return mixed
      */
-    public function __set($name, $value)
+    public function __set(string $name, $value)
     {
         throw new RuntimeException('Not allowed');
     }
 
     /**
-     * @param $name
+     * @param  string $name
      * @return mixed
      */
-    public function __isset($name)
+    public function __isset(string $name)
     {
         throw new RuntimeException('Not allowed');
     }
diff --git a/src/ClientContextInterface.php b/src/ClientContextInterface.php
index 0de20a32..95f1590e 100644
--- a/src/ClientContextInterface.php
+++ b/src/ClientContextInterface.php
@@ -178,7 +178,9 @@ use Predis\Command\Redis\Container\Search\FTCURSOR;
  * @method $this jsonforget(string $key, string $path = '$')
  * @method $this jsonget(string $key, string $indent = '', string $newline = '', string $space = '', string ...$paths)
  * @method $this jsonnumincrby(string $key, string $path, int $value)
+ * @method $this jsonmerge(string $key, string $path, string $value)
  * @method $this jsonmget(array $keys, string $path)
+ * @method $this jsonmset(string ...$keyPathValue)
  * @method $this jsonobjkeys(string $key, string $path = '$')
  * @method $this jsonobjlen(string $key, string $path = '$')
  * @method $this jsonresp(string $key, string $path = '$')
diff --git a/src/ClientInterface.php b/src/ClientInterface.php
index e46209df..924db1ec 100644
--- a/src/ClientInterface.php
+++ b/src/ClientInterface.php
@@ -187,7 +187,9 @@ use Predis\Response\Status;
  * @method int               jsonforget(string $key, string $path = '$')
  * @method string            jsonget(string $key, string $indent = '', string $newline = '', string $space = '', string ...$paths)
  * @method string            jsonnumincrby(string $key, string $path, int $value)
+ * @method Status            jsonmerge(string $key, string $path, string $value)
  * @method array             jsonmget(array $keys, string $path)
+ * @method Status            jsonmset(string ...$keyPathValue)
  * @method array             jsonobjkeys(string $key, string $path = '$')
  * @method array             jsonobjlen(string $key, string $path = '$')
  * @method array             jsonresp(string $key, string $path = '$')
diff --git a/src/Command/Redis/Container/ACL.php b/src/Command/Container/ACL.php
similarity index 93%
rename from src/Command/Redis/Container/ACL.php
rename to src/Command/Container/ACL.php
index 2699d37e..25f86cc3 100644
--- a/src/Command/Redis/Container/ACL.php
+++ b/src/Command/Container/ACL.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use Predis\Response\Status;
 
diff --git a/src/Command/Redis/Container/AbstractContainer.php b/src/Command/Container/AbstractContainer.php
similarity index 95%
rename from src/Command/Redis/Container/AbstractContainer.php
rename to src/Command/Container/AbstractContainer.php
index 6ba86d0f..950346ba 100644
--- a/src/Command/Redis/Container/AbstractContainer.php
+++ b/src/Command/Container/AbstractContainer.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use Predis\ClientInterface;
 
diff --git a/src/Command/Redis/Container/ContainerFactory.php b/src/Command/Container/ContainerFactory.php
similarity index 93%
rename from src/Command/Redis/Container/ContainerFactory.php
rename to src/Command/Container/ContainerFactory.php
index 79d3de09..68f39a33 100644
--- a/src/Command/Redis/Container/ContainerFactory.php
+++ b/src/Command/Container/ContainerFactory.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use Predis\ClientConfiguration;
 use Predis\ClientInterface;
@@ -18,7 +18,7 @@ use UnexpectedValueException;
 
 class ContainerFactory
 {
-    private const CONTAINER_NAMESPACE = "Predis\Command\Redis\Container";
+    private const CONTAINER_NAMESPACE = "Predis\Command\Container";
 
     /**
      * Mappings for class names that corresponds to PHP reserved words.
@@ -26,7 +26,7 @@ class ContainerFactory
      * @var array
      */
     private static $specialMappings = [
-        'FUNCTION' => FunctionContainer::class,
+        'FUNCTION' => FUNCTIONS::class,
     ];
 
     /**
diff --git a/src/Command/Redis/Container/ContainerInterface.php b/src/Command/Container/ContainerInterface.php
similarity index 78%
rename from src/Command/Redis/Container/ContainerInterface.php
rename to src/Command/Container/ContainerInterface.php
index ce3989b5..b4e1b0e6 100644
--- a/src/Command/Redis/Container/ContainerInterface.php
+++ b/src/Command/Container/ContainerInterface.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 interface ContainerInterface
 {
@@ -18,11 +18,11 @@ interface ContainerInterface
      * Creates Redis container command with subcommand as virtual method name
      * and sends a request to the server.
      *
-     * @param $subcommandID
-     * @param $arguments
+     * @param  string $subcommandID
+     * @param  array  $arguments
      * @return mixed
      */
-    public function __call($subcommandID, $arguments);
+    public function __call(string $subcommandID, array $arguments);
 
     /**
      * Returns containerCommandId of specific container command.
diff --git a/src/Command/Redis/Container/FunctionContainer.php b/src/Command/Container/FUNCTIONS.php
similarity index 84%
rename from src/Command/Redis/Container/FunctionContainer.php
rename to src/Command/Container/FUNCTIONS.php
index d757a44f..5b5c7860 100644
--- a/src/Command/Redis/Container/FunctionContainer.php
+++ b/src/Command/Container/FUNCTIONS.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use Predis\Response\Status;
 
@@ -18,7 +18,7 @@ use Predis\Response\Status;
  * @method string load(string $functionCode, bool $replace = 'false')
  * @method Status delete(string $libraryName)
  */
-class FunctionContainer extends AbstractContainer
+class FUNCTIONS extends AbstractContainer
 {
     public function getContainerCommandId(): string
     {
diff --git a/src/Command/Redis/Container/Json/JSONDEBUG.php b/src/Command/Container/Json/JSONDEBUG.php
similarity index 82%
rename from src/Command/Redis/Container/Json/JSONDEBUG.php
rename to src/Command/Container/Json/JSONDEBUG.php
index b20baca0..0bf4e862 100644
--- a/src/Command/Redis/Container/Json/JSONDEBUG.php
+++ b/src/Command/Container/Json/JSONDEBUG.php
@@ -10,9 +10,9 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container\Json;
+namespace Predis\Command\Container\Json;
 
-use Predis\Command\Redis\Container\AbstractContainer;
+use Predis\Command\Container\AbstractContainer;
 
 /**
  * @method array memory(string $key, string $path)
diff --git a/src/Command/Redis/Container/Search/FTCONFIG.php b/src/Command/Container/Search/FTCONFIG.php
similarity index 84%
rename from src/Command/Redis/Container/Search/FTCONFIG.php
rename to src/Command/Container/Search/FTCONFIG.php
index 9e80b8c5..5f718d3d 100644
--- a/src/Command/Redis/Container/Search/FTCONFIG.php
+++ b/src/Command/Container/Search/FTCONFIG.php
@@ -10,9 +10,9 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container\Search;
+namespace Predis\Command\Container\Search;
 
-use Predis\Command\Redis\Container\AbstractContainer;
+use Predis\Command\Container\AbstractContainer;
 use Predis\Response\Status;
 
 /**
diff --git a/src/Command/Redis/Container/Search/FTCURSOR.php b/src/Command/Container/Search/FTCURSOR.php
similarity index 85%
rename from src/Command/Redis/Container/Search/FTCURSOR.php
rename to src/Command/Container/Search/FTCURSOR.php
index 4d47c9c0..1cd4fa87 100644
--- a/src/Command/Redis/Container/Search/FTCURSOR.php
+++ b/src/Command/Container/Search/FTCURSOR.php
@@ -10,10 +10,10 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container\Search;
+namespace Predis\Command\Container\Search;
 
 use Predis\Command\Argument\Search\CursorArguments;
-use Predis\Command\Redis\Container\AbstractContainer;
+use Predis\Command\Container\AbstractContainer;
 use Predis\Response\Status;
 
 /**
diff --git a/src/Command/Redis/Json/JSONMERGE.php b/src/Command/Redis/Json/JSONMERGE.php
new file mode 100644
index 00000000..a1322283
--- /dev/null
+++ b/src/Command/Redis/Json/JSONMERGE.php
@@ -0,0 +1,29 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) 2009-2020 Daniele Alessandri
+ * (c) 2021-2023 Till Krüss
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Predis\Command\Redis\Json;
+
+use Predis\Command\Command as RedisCommand;
+
+/**
+ * @see https://redis.io/commands/json.merge/
+ *
+ * Merge a given JSON value into matching paths.
+ * Consequently, JSON values at matching paths are updated, deleted, or expanded with new children.
+ */
+class JSONMERGE extends RedisCommand
+{
+    public function getId()
+    {
+        return 'JSON.MERGE';
+    }
+}
diff --git a/src/Command/Redis/Json/JSONMSET.php b/src/Command/Redis/Json/JSONMSET.php
new file mode 100644
index 00000000..4fc6cd85
--- /dev/null
+++ b/src/Command/Redis/Json/JSONMSET.php
@@ -0,0 +1,28 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) 2009-2020 Daniele Alessandri
+ * (c) 2021-2023 Till Krüss
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Predis\Command\Redis\Json;
+
+use Predis\Command\Command as RedisCommand;
+
+/**
+ * @see https://redis.io/commands/json.mset/
+ *
+ * Set or update one or more JSON values according to the specified key-path-value triplets.
+ */
+class JSONMSET extends RedisCommand
+{
+    public function getId()
+    {
+        return 'JSON.MSET';
+    }
+}
diff --git a/src/Command/Redis/SORT.php b/src/Command/Redis/SORT.php
index 428745f6..bb62d068 100644
--- a/src/Command/Redis/SORT.php
+++ b/src/Command/Redis/SORT.php
@@ -60,9 +60,9 @@ class SORT extends RedisCommand
             }
         }
 
-        if (isset($sortParams['LIMIT']) &&
-            is_array($sortParams['LIMIT']) &&
-            count($sortParams['LIMIT']) == 2) {
+        if (isset($sortParams['LIMIT'])
+            && is_array($sortParams['LIMIT'])
+            && count($sortParams['LIMIT']) == 2) {
             $query[] = 'LIMIT';
             $query[] = $sortParams['LIMIT'][0];
             $query[] = $sortParams['LIMIT'][1];
diff --git a/src/Command/Traits/Keys.php b/src/Command/Traits/Keys.php
index a623e9ca..5dc86ad7 100644
--- a/src/Command/Traits/Keys.php
+++ b/src/Command/Traits/Keys.php
@@ -25,8 +25,8 @@ trait Keys
         $argumentsLength = count($arguments);
 
         if (
-            static::$keysArgumentPositionOffset > $argumentsLength ||
-            !is_array($arguments[static::$keysArgumentPositionOffset])
+            static::$keysArgumentPositionOffset > $argumentsLength
+            || !is_array($arguments[static::$keysArgumentPositionOffset])
         ) {
             throw new UnexpectedValueException('Wrong keys argument type or position offset');
         }
diff --git a/src/Configuration/Options.php b/src/Configuration/Options.php
index de6504f7..3fff0412 100644
--- a/src/Configuration/Options.php
+++ b/src/Configuration/Options.php
@@ -67,8 +67,8 @@ class Options implements OptionsInterface
     public function defined($option)
     {
         return
-            array_key_exists($option, $this->options) ||
-            array_key_exists($option, $this->input)
+            array_key_exists($option, $this->options)
+            || array_key_exists($option, $this->input)
         ;
     }
 
@@ -78,8 +78,8 @@ class Options implements OptionsInterface
     public function __isset($option)
     {
         return (
-            array_key_exists($option, $this->options) ||
-            array_key_exists($option, $this->input)
+            array_key_exists($option, $this->options)
+            || array_key_exists($option, $this->input)
         ) && $this->__get($option) !== null;
     }
 
diff --git a/src/Connection/RelayMethods.php b/src/Connection/RelayMethods.php
index 0e460a6e..a52c4a03 100644
--- a/src/Connection/RelayMethods.php
+++ b/src/Connection/RelayMethods.php
@@ -32,7 +32,7 @@ trait RelayMethods
      * @param  string   $pattern
      * @return bool
      */
-    public function onInvalidated(?callable $callback, ?string $pattern = null)
+    public function onInvalidated(?callable $callback, string $pattern = null)
     {
         return $this->client->onInvalidated($callback, $pattern);
     }
@@ -129,7 +129,7 @@ trait RelayMethods
      * @param  ?int    $db
      * @return bool
      */
-    public function flushMemory(?string $endpointId = null, int $db = null)
+    public function flushMemory(string $endpointId = null, int $db = null)
     {
         return $this->client->flushMemory($endpointId, $db);
     }
diff --git a/src/PubSub/AbstractConsumer.php b/src/PubSub/AbstractConsumer.php
index 653517a0..c9ea2d65 100644
--- a/src/PubSub/AbstractConsumer.php
+++ b/src/PubSub/AbstractConsumer.php
@@ -32,7 +32,7 @@ abstract class AbstractConsumer implements Iterator
     public const STATUS_SUBSCRIBED = 2;  // 0b0010
     public const STATUS_PSUBSCRIBED = 4; // 0b0100
 
-    protected $position = null;
+    protected $position;
     protected $statusFlags = self::STATUS_VALID;
 
     /**
diff --git a/tests/PHPUnit/OneOfConstraint.php b/tests/PHPUnit/OneOfConstraint.php
index 7c30cdbd..79529d38 100644
--- a/tests/PHPUnit/OneOfConstraint.php
+++ b/tests/PHPUnit/OneOfConstraint.php
@@ -44,7 +44,7 @@ class OneOfConstraint extends Constraint
     }
 
     /**
-     * @param $other
+     * @param  mixed  $other
      * @return string
      */
     protected function failureDescription($other): string
diff --git a/tests/PHPUnit/PredisTestCase.php b/tests/PHPUnit/PredisTestCase.php
index d334f59a..d67829e8 100644
--- a/tests/PHPUnit/PredisTestCase.php
+++ b/tests/PHPUnit/PredisTestCase.php
@@ -22,7 +22,7 @@ use Predis\Connection;
  */
 abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
 {
-    protected $redisServerVersion = null;
+    protected $redisServerVersion;
     protected $redisJsonVersion;
 
     /**
@@ -73,7 +73,7 @@ abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
      *
      * @return RedisCommandConstraint
      */
-    public function isRedisCommand($command = null, ?array $arguments = null): RedisCommandConstraint
+    public function isRedisCommand($command = null, array $arguments = null): RedisCommandConstraint
     {
         return new RedisCommandConstraint($command, $arguments);
     }
@@ -224,7 +224,7 @@ abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
      *
      * @return Client
      */
-    protected function createClient(?array $parameters = null, ?array $options = null, ?bool $flushdb = true): Client
+    protected function createClient(array $parameters = null, array $options = null, ?bool $flushdb = true): Client
     {
         $parameters = array_merge(
             $this->getDefaultParametersArray(),
@@ -300,7 +300,6 @@ abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
      * the default connection parameters used by Predis or a set of connection
      * parameters specified in the optional second argument.
      *
-
      * @param array|string|null $parameters Optional connection parameters
      *
      * @return MockObject|Connection\NodeConnectionInterface
@@ -362,9 +361,9 @@ abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
             $this->getName(false)
         );
 
-        if (isset($annotations['method']['requiresRedisVersion'], $annotations['method']['group']) &&
-            !empty($annotations['method']['requiresRedisVersion']) &&
-            in_array('connected', $annotations['method']['group'])
+        if (isset($annotations['method']['requiresRedisVersion'], $annotations['method']['group'])
+            && !empty($annotations['method']['requiresRedisVersion'])
+            && in_array('connected', $annotations['method']['group'])
         ) {
             return $annotations['method']['requiresRedisVersion'][0];
         }
@@ -517,9 +516,9 @@ abstract class PredisTestCase extends \PHPUnit\Framework\TestCase
             $this->getName(false)
         );
 
-        if (isset($annotations['method'][$moduleAnnotation], $annotations['method']['group']) &&
-            !empty($annotations['method'][$moduleAnnotation]) &&
-            in_array('connected', $annotations['method']['group'], true)
+        if (isset($annotations['method'][$moduleAnnotation], $annotations['method']['group'])
+            && !empty($annotations['method'][$moduleAnnotation])
+            && in_array('connected', $annotations['method']['group'], true)
         ) {
             return $annotations['method'][$moduleAnnotation][0];
         }
diff --git a/tests/PHPUnit/RedisCommandConstraint.php b/tests/PHPUnit/RedisCommandConstraint.php
index 8cb77e18..d4e0b4ec 100644
--- a/tests/PHPUnit/RedisCommandConstraint.php
+++ b/tests/PHPUnit/RedisCommandConstraint.php
@@ -25,7 +25,7 @@ class RedisCommandConstraint extends \PHPUnit\Framework\Constraint\Constraint
      * @param string|CommandInterface $command   Expected command instance or command ID
      * @param ?array                  $arguments Expected command arguments
      */
-    public function __construct($command, ?array $arguments = null)
+    public function __construct($command, array $arguments = null)
     {
         if ($command instanceof CommandInterface) {
             $this->commandID = strtoupper($command->getId());
diff --git a/tests/Predis/Cluster/PredisStrategyTest.php b/tests/Predis/Cluster/PredisStrategyTest.php
index 594c4ed3..fbf7922c 100644
--- a/tests/Predis/Cluster/PredisStrategyTest.php
+++ b/tests/Predis/Cluster/PredisStrategyTest.php
@@ -310,7 +310,7 @@ class PredisStrategyTest extends PredisTestCase
      *
      * @return array
      */
-    protected function getExpectedCommands(?string $type = null): array
+    protected function getExpectedCommands(string $type = null): array
     {
         $commands = [
             /* commands operating on the key space */
diff --git a/tests/Predis/Cluster/RedisStrategyTest.php b/tests/Predis/Cluster/RedisStrategyTest.php
index d19eec85..dd570d53 100644
--- a/tests/Predis/Cluster/RedisStrategyTest.php
+++ b/tests/Predis/Cluster/RedisStrategyTest.php
@@ -333,7 +333,7 @@ class RedisStrategyTest extends PredisTestCase
      *
      * @return array
      */
-    protected function getExpectedCommands(?string $type = null): array
+    protected function getExpectedCommands(string $type = null): array
     {
         $commands = [
             /* commands operating on the key space */
diff --git a/tests/Predis/Command/Redis/Container/AbstractContainerTest.php b/tests/Predis/Command/Container/AbstractContainerTest.php
similarity index 98%
rename from tests/Predis/Command/Redis/Container/AbstractContainerTest.php
rename to tests/Predis/Command/Container/AbstractContainerTest.php
index 7a91307e..857f7502 100644
--- a/tests/Predis/Command/Redis/Container/AbstractContainerTest.php
+++ b/tests/Predis/Command/Container/AbstractContainerTest.php
@@ -10,7 +10,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use PHPUnit\Framework\TestCase;
 use Predis\ClientInterface;
diff --git a/tests/Predis/Command/Redis/Container/ContainerFactoryTest.php b/tests/Predis/Command/Container/ContainerFactoryTest.php
similarity index 93%
rename from tests/Predis/Command/Redis/Container/ContainerFactoryTest.php
rename to tests/Predis/Command/Container/ContainerFactoryTest.php
index f98901e1..2aa13044 100644
--- a/tests/Predis/Command/Redis/Container/ContainerFactoryTest.php
+++ b/tests/Predis/Command/Container/ContainerFactoryTest.php
@@ -10,12 +10,12 @@
  * file that was distributed with this source code.
  */
 
-namespace Predis\Command\Redis\Container;
+namespace Predis\Command\Container;
 
 use PHPUnit\Framework\MockObject\MockObject;
 use PHPUnit\Framework\TestCase;
 use Predis\ClientInterface;
-use Predis\Command\Redis\Container\Search\FTCONFIG;
+use Predis\Command\Container\Search\FTCONFIG;
 use UnexpectedValueException;
 
 class ContainerFactoryTest extends TestCase
@@ -73,7 +73,7 @@ class ContainerFactoryTest extends TestCase
     public function containerProvider(): array
     {
         return [
-            'core command' => ['function', FunctionContainer::class],
+            'core command' => ['function', FUNCTIONS::class],
             'module command' => ['ftconfig', FTCONFIG::class],
         ];
     }
diff --git a/tests/Predis/Command/Redis/EVALSHA_RO_Test.php b/tests/Predis/Command/Redis/EVALSHA_RO_Test.php
index 596e4c38..74ad40ce 100644
--- a/tests/Predis/Command/Redis/EVALSHA_RO_Test.php
+++ b/tests/Predis/Command/Redis/EVALSHA_RO_Test.php
@@ -61,10 +61,10 @@ class EVALSHA_RO_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider scriptsProvider
-     * @param string $script
-     * @param array  $keys
-     * @param array  $arguments
-     * @param $expectedResponse
+     * @param  string $script
+     * @param  array  $keys
+     * @param  array  $arguments
+     * @param  mixed  $expectedResponse
      * @return void
      * @requiresRedisVersion >= 7.0.0
      */
diff --git a/tests/Predis/Command/Redis/EVAL_RO_Test.php b/tests/Predis/Command/Redis/EVAL_RO_Test.php
index 89c93d40..cdeb5b70 100644
--- a/tests/Predis/Command/Redis/EVAL_RO_Test.php
+++ b/tests/Predis/Command/Redis/EVAL_RO_Test.php
@@ -61,11 +61,11 @@ class EVAL_RO_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider scriptsProvider
-     * @param array  $dictionary
-     * @param string $script
-     * @param array  $keys
-     * @param array  $arguments
-     * @param $expectedResponse
+     * @param  array  $dictionary
+     * @param  string $script
+     * @param  array  $keys
+     * @param  array  $arguments
+     * @param  mixed  $expectedResponse
      * @return void
      * @requiresRedisVersion >= 7.0.0
      */
diff --git a/tests/Predis/Command/Redis/EXPIREAT_Test.php b/tests/Predis/Command/Redis/EXPIREAT_Test.php
index 44829683..cee43824 100644
--- a/tests/Predis/Command/Redis/EXPIREAT_Test.php
+++ b/tests/Predis/Command/Redis/EXPIREAT_Test.php
@@ -166,14 +166,14 @@ class EXPIREAT_Test extends PredisCommandTestCase
                 ['noExpiry', time() + 10, 'XX'],
             ],
             'only if new expiry is greater then current one' => [
-                ['newExpiryLower', 'value', 'EXAT', time() + 1000],
-                ['newExpiryGreater', 'value', 'EXAT', time() + 10],
+                ['newExpiryLower', 'value', 'EX', 1000],
+                ['newExpiryGreater', 'value', 'EX', 10],
                 ['newExpiryGreater', time() + 20, 'GT'],
                 ['newExpiryLower', time() + 20, 'GT'],
             ],
             'only if new expiry is lower then current one' => [
-                ['newExpiryLower', 'value', 'EXAT', time() + 1000],
-                ['newExpiryGreater', 'value', 'EXAT', time() + 10],
+                ['newExpiryLower', 'value', 'EX', 1000],
+                ['newExpiryGreater', 'value', 'EX', 10],
                 ['newExpiryLower', time() + 20, 'LT'],
                 ['newExpiryGreater', time() + 20, 'LT'],
             ],
diff --git a/tests/Predis/Command/Redis/FCALL_RO_Test.php b/tests/Predis/Command/Redis/FCALL_RO_Test.php
index a90695f3..87a3d334 100644
--- a/tests/Predis/Command/Redis/FCALL_RO_Test.php
+++ b/tests/Predis/Command/Redis/FCALL_RO_Test.php
@@ -113,8 +113,8 @@ class FCALL_RO_Test extends PredisCommandTestCase
         );
 
         if (
-            isset($annotations['method']['group']) &&
-            in_array('connected', $annotations['method']['group'], true)
+            isset($annotations['method']['group'])
+            && in_array('connected', $annotations['method']['group'], true)
         ) {
             $redis = $this->getClient();
             $redis->function->delete(self::LIB_NAME);
diff --git a/tests/Predis/Command/Redis/FCALL_Test.php b/tests/Predis/Command/Redis/FCALL_Test.php
index 8729e6f1..4e4ab055 100644
--- a/tests/Predis/Command/Redis/FCALL_Test.php
+++ b/tests/Predis/Command/Redis/FCALL_Test.php
@@ -78,9 +78,9 @@ class FCALL_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider functionsProvider
-     * @param string $function
-     * @param array  $functionArguments
-     * @param $expectedResponse
+     * @param  string $function
+     * @param  array  $functionArguments
+     * @param  mixed  $expectedResponse
      * @return void
      * @requiresRedisVersion >= 7.0.0
      */
diff --git a/tests/Predis/Command/Redis/Json/JSONMERGE_Test.php b/tests/Predis/Command/Redis/Json/JSONMERGE_Test.php
new file mode 100644
index 00000000..b9cb7a74
--- /dev/null
+++ b/tests/Predis/Command/Redis/Json/JSONMERGE_Test.php
@@ -0,0 +1,103 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) 2009-2020 Daniele Alessandri
+ * (c) 2021-2023 Till Krüss
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Predis\Command\Redis\Json;
+
+use Predis\Command\Redis\PredisCommandTestCase;
+
+class JSONMERGE_Test extends PredisCommandTestCase
+{
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedCommand(): string
+    {
+        return JSONMERGE::class;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedId(): string
+    {
+        return 'JSONMERGE';
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testFilterArguments(): void
+    {
+        $arguments = ['key', '$..', '{"a":2}'];
+        $expected = ['key', '$..', '{"a":2}'];
+
+        $command = $this->getCommand();
+        $command->setArguments($arguments);
+
+        $this->assertSame($expected, $command->getArguments());
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testParseResponse(): void
+    {
+        $this->assertSame(1, $this->getCommand()->parseResponse(1));
+    }
+
+    /**
+     * @dataProvider jsonProvider
+     * @group connected
+     * @param  array  $setArguments
+     * @param  array  $mergeArguments
+     * @param  string $expectedResponse
+     * @return void
+     * @requiresRedisJsonVersion >= 2.6.0
+     */
+    public function testMergeCorrectlyMergeJsonValues(
+        array $setArguments,
+        array $mergeArguments,
+        string $expectedResponse
+    ): void {
+        $redis = $this->getClient();
+
+        $this->assertEquals('OK', $redis->jsonset(...$setArguments));
+        $this->assertEquals('OK', $redis->jsonmerge(...$mergeArguments));
+        $this->assertEquals($expectedResponse, $redis->jsonget('key'));
+    }
+
+    public function jsonProvider(): array
+    {
+        return [
+            'create non-existing value' => [
+                ['key', '$', '{"a":2}'],
+                ['key', '$.b', '8'],
+                '{"a":2,"b":8}',
+            ],
+            'replace existing value' => [
+                ['key', '$', '{"a":2}'],
+                ['key', '$.a', '3'],
+                '{"a":3}',
+            ],
+            'replace an array' => [
+                ['key', '$', '{"a":[2,4,6,8]}'],
+                ['key', '$.a', '[10,12]'],
+                '{"a":[10,12]}',
+            ],
+            'merge in multiple-paths' => [
+                ['key', '$', '{"f1": {"a":1}, "f2":{"a":2}}'],
+                ['key', '$', '{"f2":{"a":3, "b":4}, "f3":[2,4,6]}'],
+                '{"f1":{"a":1},"f2":{"a":3,"b":4},"f3":[2,4,6]}',
+            ],
+        ];
+    }
+}
diff --git a/tests/Predis/Command/Redis/Json/JSONMSET_Test.php b/tests/Predis/Command/Redis/Json/JSONMSET_Test.php
new file mode 100644
index 00000000..2083d39c
--- /dev/null
+++ b/tests/Predis/Command/Redis/Json/JSONMSET_Test.php
@@ -0,0 +1,85 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) 2009-2020 Daniele Alessandri
+ * (c) 2021-2023 Till Krüss
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Predis\Command\Redis\Json;
+
+use Predis\Command\Redis\PredisCommandTestCase;
+use Predis\Response\ServerException;
+
+class JSONMSET_Test extends PredisCommandTestCase
+{
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedCommand(): string
+    {
+        return JSONMSET::class;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedId(): string
+    {
+        return 'JSONMSET';
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testFilterArguments(): void
+    {
+        $arguments = ['key', '$..', 'value', 'key1', '$', 'value1'];
+        $expected = ['key', '$..', 'value', 'key1', '$', 'value1'];
+
+        $command = $this->getCommand();
+        $command->setArguments($arguments);
+
+        $this->assertSame($expected, $command->getArguments());
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testParseResponse(): void
+    {
+        $this->assertSame(1, $this->getCommand()->parseResponse(1));
+    }
+
+    /**
+     * @group connected
+     * @return void
+     * @requiresRedisJsonVersion >= 2.6.0
+     */
+    public function testSetMultipleJsonDocuments(): void
+    {
+        $redis = $this->getClient();
+
+        $this->assertEquals('OK', $redis->jsonmset('doc1', '$', '{"a":2}', 'doc2', '$', '{"b":3}'));
+        $this->assertEquals(['[{"a":2}]', '[{"b":3}]'], $redis->jsonmget(['doc1', 'doc2'], '$'));
+    }
+
+    /**
+     * @group connected
+     * @return void
+     * @requiresRedisJsonVersion >= 2.6.0
+     */
+    public function testThrowsExceptionOnNewValuesNotInTheRootPath(): void
+    {
+        $redis = $this->getClient();
+
+        $this->expectException(ServerException::class);
+        $this->expectExceptionMessage('ERR new objects must be created at the root');
+
+        $redis->jsonmset('doc1', '$', '{"a":2}', 'doc2', '$.f', '{"b":3}');
+    }
+}
diff --git a/tests/Predis/Command/Redis/LCS_Test.php b/tests/Predis/Command/Redis/LCS_Test.php
index 839084a3..72cb5c6c 100644
--- a/tests/Predis/Command/Redis/LCS_Test.php
+++ b/tests/Predis/Command/Redis/LCS_Test.php
@@ -58,9 +58,9 @@ class LCS_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider stringsProvider
-     * @param array $stringsArguments
-     * @param array $functionArguments
-     * @param $expectedResponse
+     * @param  array $stringsArguments
+     * @param  array $functionArguments
+     * @param  mixed $expectedResponse
      * @return void
      * @requiresRedisVersion >= 7.0.0
      */
diff --git a/tests/Predis/Command/Redis/Search/FTSEARCH_Test.php b/tests/Predis/Command/Redis/Search/FTSEARCH_Test.php
index 58254af5..dfca91d5 100644
--- a/tests/Predis/Command/Redis/Search/FTSEARCH_Test.php
+++ b/tests/Predis/Command/Redis/Search/FTSEARCH_Test.php
@@ -113,6 +113,9 @@ class FTSEARCH_Test extends PredisCommandTestCase
         $ftCreateResponse = $redis->ftcreate('idx_hash', $schema, $ftCreateArguments);
         $this->assertEquals('OK', $ftCreateResponse);
 
+        // Timeout to make sure that index created before search performed.
+        usleep(2000);
+
         $ftSearchArguments = new SearchArguments();
         $ftSearchArguments->addReturn(1, 'should_return');
 
diff --git a/tests/Predis/Command/Redis/ZINTERCARD_Test.php b/tests/Predis/Command/Redis/ZINTERCARD_Test.php
index d307eff1..7923b4d8 100644
--- a/tests/Predis/Command/Redis/ZINTERCARD_Test.php
+++ b/tests/Predis/Command/Redis/ZINTERCARD_Test.php
@@ -110,8 +110,8 @@ class ZINTERCARD_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider unexpectedValuesProvider
-     * @param $keys
-     * @param $limit
+     * @param  mixed  $keys
+     * @param  mixed  $limit
      * @param  string $expectedExceptionMessage
      * @return void
      * @requiresRedisVersion >= 7.0.0
diff --git a/tests/Predis/Command/Redis/ZINTERSTORE_Test.php b/tests/Predis/Command/Redis/ZINTERSTORE_Test.php
index 3c7229a9..bad586c1 100644
--- a/tests/Predis/Command/Redis/ZINTERSTORE_Test.php
+++ b/tests/Predis/Command/Redis/ZINTERSTORE_Test.php
@@ -133,9 +133,9 @@ class ZINTERSTORE_Test extends PredisCommandTestCase
 
     /**
      * @dataProvider unexpectedValueProvider
-     * @param string $destination
-     * @param $keys
-     * @param $weights
+     * @param  string $destination
+     * @param  mixed  $keys
+     * @param  mixed  $weights
      * @param  string $aggregate
      * @param  string $expectedExceptionMessage
      * @return void
diff --git a/tests/Predis/Command/Redis/ZINTER_Test.php b/tests/Predis/Command/Redis/ZINTER_Test.php
index 9390cd5a..22eaef5b 100644
--- a/tests/Predis/Command/Redis/ZINTER_Test.php
+++ b/tests/Predis/Command/Redis/ZINTER_Test.php
@@ -127,8 +127,8 @@ class ZINTER_Test extends PredisCommandTestCase
 
     /**
      * @dataProvider unexpectedValueProvider
-     * @param $keys
-     * @param $weights
+     * @param  mixed  $keys
+     * @param  mixed  $weights
      * @param  string $aggregate
      * @param  bool   $withScores
      * @param  string $expectedExceptionMessage
diff --git a/tests/Predis/Command/Redis/ZRANGESTORE_Test.php b/tests/Predis/Command/Redis/ZRANGESTORE_Test.php
index d60e4ad6..2989a3ed 100644
--- a/tests/Predis/Command/Redis/ZRANGESTORE_Test.php
+++ b/tests/Predis/Command/Redis/ZRANGESTORE_Test.php
@@ -102,14 +102,14 @@ class ZRANGESTORE_Test extends PredisCommandTestCase
     /**
      * @group connected
      * @dataProvider unexpectedValuesProvider
-     * @param int|string  $min
-     * @param int|string  $max
-     * @param string|bool $by
-     * @param $rev
-     * @param $limit
-     * @param  int    $offset
-     * @param  int    $count
-     * @param  string $expectedExceptionMessage
+     * @param  int|string  $min
+     * @param  int|string  $max
+     * @param  string|bool $by
+     * @param              $rev
+     * @param              $limit
+     * @param  int         $offset
+     * @param  int         $count
+     * @param  string      $expectedExceptionMessage
      * @return void
      * @requiresRedisVersion >= 6.2.0
      */
diff --git a/tests/Predis/Command/Redis/ZUNIONSTORE_Test.php b/tests/Predis/Command/Redis/ZUNIONSTORE_Test.php
index 3bc036a4..2d9e8532 100644
--- a/tests/Predis/Command/Redis/ZUNIONSTORE_Test.php
+++ b/tests/Predis/Command/Redis/ZUNIONSTORE_Test.php
@@ -133,9 +133,9 @@ class ZUNIONSTORE_Test extends PredisCommandTestCase
 
     /**
      * @dataProvider unexpectedValueProvider
-     * @param string $destination
-     * @param $keys
-     * @param $weights
+     * @param  string $destination
+     * @param         $keys
+     * @param         $weights
      * @param  string $aggregate
      * @param  string $expectedExceptionMessage
      * @return void
diff --git a/tests/Predis/Command/Redis/ZUNION_Test.php b/tests/Predis/Command/Redis/ZUNION_Test.php
index 2e1d3ed4..0cd033c9 100644
--- a/tests/Predis/Command/Redis/ZUNION_Test.php
+++ b/tests/Predis/Command/Redis/ZUNION_Test.php
@@ -101,8 +101,8 @@ class ZUNION_Test extends PredisCommandTestCase
 
     /**
      * @dataProvider unexpectedValueProvider
-     * @param $keys
-     * @param $weights
+     * @param         $keys
+     * @param         $weights
      * @param  string $aggregate
      * @param  bool   $withScores
      * @param  string $expectedExceptionMessage
diff --git a/tests/Predis/Replication/ReplicationStrategyTest.php b/tests/Predis/Replication/ReplicationStrategyTest.php
index ca9ae4bd..128bbce4 100644
--- a/tests/Predis/Replication/ReplicationStrategyTest.php
+++ b/tests/Predis/Replication/ReplicationStrategyTest.php
@@ -390,7 +390,7 @@ class ReplicationStrategyTest extends PredisTestCase
      *
      * @return array
      */
-    protected function getExpectedCommands(?string $type = null): array
+    protected function getExpectedCommands(string $type = null): array
     {
         $commands = [
             /* commands operating on the connection */