Extended support by implementing TDIGEST.MAX command (#1099)

* Added support for TDIGEST.MAX command

* Codestyle fixes

---------

Co-authored-by: Vladyslav Vildanov <vladyslavvildanov@Vladyslav-Vildanov-MacBook-Pro.local>

src/ClientContextInterface.php

@@ -179,6 +179,7 @@ use Predis\Command\CommandInterface;
  * @method $this tdigestcdf(string $key, int ...$value)
  * @method $this tdigestcreate(string $key, int $compression = 0)
  * @method $this tdigestinfo(string $key)
+ * @method $this tdigestmax(string $key)
  * @method $this zadd($key, array $membersAndScoresDictionary)
  * @method $this zcard($key)
  * @method $this zcount($key, $min, $max)

src/ClientInterface.php

@@ -189,6 +189,7 @@ use Predis\Response\Status;
  * @method array             tdigestcdf(string $key, int ...$value)
  * @method Status            tdigestcreate(string $key, int $compression = 0)
  * @method array             tdigestinfo(string $key)
+ * @method string            tdigestmax(string $key)
  * @method string            xadd(string $key, array $dictionary, string $id = '*', array $options = null)
  * @method int               xdel(string $key, string ...$id)
  * @method int               xlen(string $key)

src/Command/Redis/TDigest/TDIGESTMAX.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\TDigest;
+
+use Predis\Command\Command as RedisCommand;
+
+/**
+ * @see https://redis.io/commands/tdigest.max/
+ *
+ * Returns the maximum observation value from a t-digest sketch.
+ */
+class TDIGESTMAX extends RedisCommand
+{
+    public function getId()
+    {
+        return 'TDIGEST.MAX';
+    }
+}

tests/Predis/Command/Redis/TDigest/TDIGESTMAX_Test.php

@@ -0,0 +1,92 @@
+<?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\TDigest;
+
+use Predis\Command\Redis\PredisCommandTestCase;
+use Predis\Response\ServerException;
+
+class TDIGESTMAX_Test extends PredisCommandTestCase
+{
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedCommand(): string
+    {
+        return TDIGESTMAX::class;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function getExpectedId(): string
+    {
+        return 'TDIGESTMAX';
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testFilterArguments(): void
+    {
+        $actualArguments = ['key'];
+        $expectedArguments = ['key'];
+
+        $command = $this->getCommand();
+        $command->setArguments($actualArguments);
+
+        $this->assertSameValues($expectedArguments, $command->getArguments());
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testParseResponse(): void
+    {
+        $this->assertSame(1, $this->getCommand()->parseResponse(1));
+    }
+
+    /**
+     * @group connected
+     * @return void
+     * @requiresRedisBfVersion >= 2.4.0
+     */
+    public function testReturnsMaxValueFromGivenSketch(): void
+    {
+        $redis = $this->getClient();
+
+        $redis->tdigestcreate('key');
+        $redis->tdigestcreate('empty_key');
+
+        $redis->tdigestadd('key', 3, 2, 4, 5, 1);
+
+        $actualResponse = $redis->tdigestmax('key');
+
+        $this->assertSame('5', $actualResponse);
+        $this->assertSame('nan', $redis->tdigestmax('empty_key'));
+    }
+
+    /**
+     * @group connected
+     * @return void
+     * @requiresRedisBfVersion >= 2.4.0
+     */
+    public function testThrowsExceptionOnNonExistingTDigestSketch(): void
+    {
+        $redis = $this->getClient();
+
+        $this->expectException(ServerException::class);
+        $this->expectExceptionMessage('ERR T-Digest: key does not exist');
+
+        $redis->tdigestmax('key');
+    }
+}