Return NAN for RESP3 NaN double payloads (#1718)

parseDouble() fell through to a float cast for ',nan', and
(float) 'nan' evaluates to 0.0 in PHP, so a NaN score silently became
a valid zero. Return NAN instead. The RESP3 specification also notes
that Redis before 7.2 may emit any libc representation of NaN
('-nan', 'NAN', 'nan(char-sequence)') and that clients should handle
them, so those spellings are accepted as well.

The TDigest RESP3 tests asserted 0 or null for empty sketches, which
only passed because of the collapsed 0.0 (null == 0.0 loosely); their
RESP2 counterparts already assert the string 'nan' for the same
replies. They now assert NaN.

Note for reviewers: json_encode() throws on NAN, so consumers who
serialize raw replies must handle it; the previous behavior hid NaN
behind a plausible-looking 0.0 instead.

.github/workflows/spellcheck.yml

@@ -13,7 +13,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v7
       - name: Check Spelling
-        uses: rojopolis/spellcheck-github-actions@0.63.0
+        uses: rojopolis/spellcheck-github-actions@0.66.0
         with:
           config_path: .github/spellcheck-settings.yml
           task_name: Markdown

.github/workflows/tests.yml

@@ -85,13 +85,13 @@ jobs:
         uses: actions/checkout@v7
 
       - name: Start Redis standalone image
-        uses: hoverkraft-tech/compose-action@v3.0.0
+        uses: hoverkraft-tech/compose-action@v3.1.0
         with:
           compose-file: .github/docker-compose.yml
           services: ${{ env.DOCKER_SERVICE }}
 
       - name: Start Redis unprotected image
-        uses: hoverkraft-tech/compose-action@v3.0.0
+        uses: hoverkraft-tech/compose-action@v3.1.0
         if: ${{ matrix.redis > '4.0' }}
         with:
           compose-file: .github/docker-compose.yml
@@ -99,7 +99,7 @@ jobs:
 
       - name: Start Redis stack image
         id: stack_infra
-        uses: hoverkraft-tech/compose-action@v3.0.0
+        uses: hoverkraft-tech/compose-action@v3.1.0
         if: ${{ matrix.redis >= '7.2' && matrix.redis < '8.0' }}
         with:
           compose-file: .github/docker-compose.yml
@@ -107,7 +107,7 @@ jobs:
 
       - name: Start Redis cluster image
         id: cluster_infra
-        uses: hoverkraft-tech/compose-action@v3.0.0
+        uses: hoverkraft-tech/compose-action@v3.1.0
         if: ${{ matrix.redis > '4.0' }}
         with:
           compose-file: .github/docker-compose.yml
@@ -115,7 +115,7 @@ jobs:
 
       - name: Start Redis sentinels image
         id: sentinel_infra
-        uses: hoverkraft-tech/compose-action@v3.0.0
+        uses: hoverkraft-tech/compose-action@v3.1.0
         if: ${{ matrix.redis > '4.0' }}
         with:
           compose-file: .github/docker-compose.yml

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## Changelog
 
+## Unreleased
+### Changed
+- Changed RESP3 double parsing to return `NAN` for NaN payloads instead of `0.0`
+
 ## v3.6.0 (2026-08-14)
 ### Added
 - Added support for new TS commands + Indonesian language support integration test (#1695)

VERSION

@@ -1 +1 @@
-3.6.0
+3.6.1-dev

src/Client.php

@@ -56,7 +56,7 @@ use Traversable;
  */
 class Client implements ClientInterface, IteratorAggregate
 {
-    public const VERSION = '3.6.0';
+    public const VERSION = '3.6.1-dev';
 
     /** @var OptionsInterface */
     private $options;

src/Connection/Factory.php

@@ -208,13 +208,15 @@ class Factory implements FactoryInterface
             );
         }
 
-        $connection->addConnectCommand(
-            new RawCommand('CLIENT', ['SETINFO', 'LIB-NAME', $this->buildLibraryName()])
-        );
+        if ($parameters->client_info ?? true) {
+            $connection->addConnectCommand(
+                new RawCommand('CLIENT', ['SETINFO', 'LIB-NAME', $this->buildLibraryName()])
+            );
 
-        $connection->addConnectCommand(
-            new RawCommand('CLIENT', ['SETINFO', 'LIB-VER', Client::VERSION])
-        );
+            $connection->addConnectCommand(
+                new RawCommand('CLIENT', ['SETINFO', 'LIB-VER', Client::VERSION])
+            );
+        }
 
         if (isset($parameters->database) && strlen($parameters->database)) {
             $connection->addConnectCommand(

src/Connection/ParametersInterface.php

@@ -36,7 +36,7 @@ use Predis\Retry\Retry;
  * @property string $database           Database index (see the SELECT command).
  * @property bool   $async_connect      Performs the connect() operation asynchronously.
  * @property bool   $tcp_nodelay        Toggles the Nagle's algorithm for coalescing.
- * @property bool   $client_info        Whether to set LIB-NAME and LIB-VER when connecting.
+ * @property bool   $client_info        Whether to set LIB-NAME and LIB-VER when connecting, enabled by default.
  * @property Retry  $retry              Retry configuration
  * @property bool   $cache              (Relay only) Whether to use in-memory caching.
  * @property string $serializer         (Relay only) Serializer used for data serialization.

src/Protocol/Parser/Strategy/Resp3Strategy.php

@@ -63,10 +63,18 @@ class Resp3Strategy extends Resp2Strategy
      */
     protected function parseDouble(string $string): float
     {
-        if ($string === 'inf' || $string === '-inf') {
+        if ($string === 'inf') {
             return INF;
         }
 
+        if ($string === '-inf') {
+            return -INF;
+        }
+
+        if (preg_match('/^-?nan(\(.*\))?$/i', $string) === 1) {
+            return NAN;
+        }
+
         return (float) $string;
     }
 

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

@@ -118,7 +118,11 @@ class TDIGESTBYRANK_Test extends PredisCommandTestCase
         $actualResponse = $redis->tdigestbyrank('key', 0, 1, 2, 3, 4, 5, 6);
 
         $this->assertEquals($expectedResponse, $actualResponse);
-        $this->assertEquals([null, null], $redis->tdigestbyrank('empty_key', 0, 1));
+        $emptyResponse = $redis->tdigestbyrank('empty_key', 0, 1);
+        $this->assertCount(2, $emptyResponse);
+        foreach ($emptyResponse as $value) {
+            $this->assertNan($value);
+        }
     }
 
     /**

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

@@ -118,7 +118,11 @@ class TDIGESTBYREVRANK_Test extends PredisCommandTestCase
         $actualResponse = $redis->tdigestbyrevrank('key', 0, 1, 2, 3, 4, 5, 6);
 
         $this->assertEquals($expectedResponse, $actualResponse);
-        $this->assertEquals([null, null], $redis->tdigestbyrevrank('empty_key', 0, 1));
+        $emptyResponse = $redis->tdigestbyrevrank('empty_key', 0, 1);
+        $this->assertCount(2, $emptyResponse);
+        foreach ($emptyResponse as $value) {
+            $this->assertNan($value);
+        }
     }
 
     /**

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

@@ -118,7 +118,11 @@ class TDIGESTCDF_Test extends PredisCommandTestCase
         $actualResponse = $redis->tdigestcdf('key', 0, 1, 2, 3, 4);
 
         $this->assertSameWithPrecision($expectedResponse, $actualResponse, 5);
-        $this->assertSame([0.0, 0.0], $redis->tdigestcdf('empty_key', 0, 1));
+        $emptyResponse = $redis->tdigestcdf('empty_key', 0, 1);
+        $this->assertCount(2, $emptyResponse);
+        foreach ($emptyResponse as $value) {
+            $this->assertNan($value);
+        }
     }
 
     /**

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

@@ -116,7 +116,7 @@ class TDIGESTMAX_Test extends PredisCommandTestCase
         $actualResponse = $redis->tdigestmax('key');
 
         $this->assertEquals('5', $actualResponse);
-        $this->assertEquals(0, $redis->tdigestmax('empty_key'));
+        $this->assertNan($redis->tdigestmax('empty_key'));
     }
 
     /**

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

@@ -116,7 +116,7 @@ class TDIGESTMIN_Test extends PredisCommandTestCase
         $actualResponse = $redis->tdigestmin('key');
 
         $this->assertEquals('1', $actualResponse);
-        $this->assertEquals(0, $redis->tdigestmin('empty_key'));
+        $this->assertNan($redis->tdigestmin('empty_key'));
     }
 
     /**

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

@@ -118,7 +118,11 @@ class TDIGESTQUANTILE_Test extends PredisCommandTestCase
         $this->assertEquals([1.0, 2.0, 3.0, 3.0, 4.0, 4.0, 4.0, 5.0, 5.0, 5.0, 5.0], $quantileResponse);
 
         $redis->tdigestcreate('empty_key');
-        $this->assertEquals([null, null], $redis->tdigestquantile('empty_key', 0.0, 0.1));
+        $emptyResponse = $redis->tdigestquantile('empty_key', 0.0, 0.1);
+        $this->assertCount(2, $emptyResponse);
+        foreach ($emptyResponse as $value) {
+            $this->assertNan($value);
+        }
     }
 
     /**

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

@@ -129,10 +129,11 @@ class TDIGESTRESET_Test extends PredisCommandTestCase
 
         $this->assertEquals('OK', $actualResponse);
         $this->assertSame(500, $info['Compression']);
-        $this->assertEquals(
-            [null, null, null, null, null, null],
-            $redis->tdigestbyrank('key', 0, 1, 2, 3, 4, 5)
-        );
+        $resetResponse = $redis->tdigestbyrank('key', 0, 1, 2, 3, 4, 5);
+        $this->assertCount(6, $resetResponse);
+        foreach ($resetResponse as $value) {
+            $this->assertNan($value);
+        }
     }
 
     /**

tests/Predis/Connection/FactoryTest.php

@@ -585,6 +585,24 @@ class FactoryTest extends PredisTestCase
         $this->assertSame(['SETINFO', 'LIB-VER', Client::VERSION], $initCommands[2]->getArguments());
     }
 
+    /**
+     * @group disconnected
+     * @return void
+     */
+    public function testDoesNotSetClientNameAndVersionOnConnectionWithClientInfoDisabled(): void
+    {
+        $parameters = ['client_info' => false];
+
+        $factory = new Factory();
+        $connection = $factory->create($parameters);
+        $initCommands = $connection->getInitCommands();
+
+        $this->assertCount(1, $initCommands);
+        $this->assertInstanceOf(RawCommand::class, $initCommands[0]);
+        $this->assertSame('HELLO', $initCommands[0]->getId());
+        $this->assertSame([2, 'SETNAME', 'predis'], $initCommands[0]->getArguments());
+    }
+
     /**
      * @group disconnected
      */

tests/Predis/Protocol/Parser/Strategy/Resp3StrategyTest.php

@@ -60,11 +60,24 @@ class Resp3StrategyTest extends PredisTestCase
      * @param  string $data
      * @return void
      */
-    public function testParseDataReturnsFloatInfinityOnInfinityOrNegativeInfinity(string $data): void
+    public function testParseDataReturnsFloatInfinityOnInfinityOrNegativeInfinity(string $data, float $expectedValue): void
     {
         $actualResponse = $this->strategy->parseData($data);
 
-        $this->assertInfinite($actualResponse);
+        $this->assertSame($expectedValue, $actualResponse);
+    }
+
+    /**
+     * @dataProvider nanProvider
+     * @group disconnected
+     * @param  string $data
+     * @return void
+     */
+    public function testParseDataReturnsFloatNanOnNanValue(string $data): void
+    {
+        $actualResponse = $this->strategy->parseData($data);
+
+        $this->assertNan($actualResponse);
     }
 
     /**
@@ -166,8 +179,18 @@ class Resp3StrategyTest extends PredisTestCase
     public function infinityProvider(): array
     {
         return [
-            'positive infinity' => [",inf\r\n"],
-            'negative infinity' => [",-inf\r\n"],
+            'positive infinity' => [",inf\r\n", INF],
+            'negative infinity' => [",-inf\r\n", -INF],
+        ];
+    }
+
+    public function nanProvider(): array
+    {
+        return [
+            'canonical nan' => [",nan\r\n"],
+            'negative nan' => [",-nan\r\n"],
+            'uppercase nan' => [",NAN\r\n"],
+            'nan with payload' => [",nan(ind)\r\n"],
         ];
     }