diff --git a/src/Commands/QueueClear.php b/src/Commands/QueueClear.php
index 5d8e175..0080454 100644
--- a/src/Commands/QueueClear.php
+++ b/src/Commands/QueueClear.php
@@ -50,7 +50,8 @@ class QueueClear extends BaseCommand
     public function run(array $params)
     {
         // Read params
-        if (! $queue = array_shift($params)) {
+        $queue = array_shift($params);
+        if ($queue === null) {
             CLI::error('The queueName is not specified.');
 
             return EXIT_ERROR;
diff --git a/src/Commands/QueueForget.php b/src/Commands/QueueForget.php
index 7a02ee3..df55a5d 100644
--- a/src/Commands/QueueForget.php
+++ b/src/Commands/QueueForget.php
@@ -50,7 +50,8 @@ class QueueForget extends BaseCommand
     public function run(array $params)
     {
         // Read params
-        if (! $id = array_shift($params)) {
+        $id = array_shift($params);
+        if ($id === null) {
             CLI::error('The ID of the failed job is not specified.');
 
             return EXIT_ERROR;
diff --git a/src/Commands/QueueRetry.php b/src/Commands/QueueRetry.php
index 6bbb43b..ad993b5 100644
--- a/src/Commands/QueueRetry.php
+++ b/src/Commands/QueueRetry.php
@@ -59,7 +59,8 @@ class QueueRetry extends BaseCommand
     public function run(array $params)
     {
         // Read params
-        if (! $id = array_shift($params)) {
+        $id = array_shift($params);
+        if ($id === null) {
             CLI::error('The ID of the failed job is not specified.');
 
             return EXIT_ERROR;
diff --git a/src/Commands/QueueStop.php b/src/Commands/QueueStop.php
index 91085d1..0becf7a 100644
--- a/src/Commands/QueueStop.php
+++ b/src/Commands/QueueStop.php
@@ -58,7 +58,8 @@ class QueueStop extends BaseCommand
     public function run(array $params)
     {
         // Read params
-        if (! $queue = array_shift($params)) {
+        $queue = array_shift($params);
+        if ($queue === null) {
             CLI::error('The queueName is not specified.');
 
             return EXIT_ERROR;
diff --git a/src/Commands/QueueWork.php b/src/Commands/QueueWork.php
index 7f19bd8..18235c3 100644
--- a/src/Commands/QueueWork.php
+++ b/src/Commands/QueueWork.php
@@ -80,7 +80,8 @@ public function run(array $params)
         $waiting       = false;
 
         // Read queue name from params
-        if (! $queue = array_shift($params)) {
+        $queue = array_shift($params);
+        if ($queue === null) {
             CLI::error('The queueName is not specified.');
 
             return EXIT_ERROR;
diff --git a/src/Handlers/PredisHandler.php b/src/Handlers/PredisHandler.php
index 32f52f8..ea2267c 100644
--- a/src/Handlers/PredisHandler.php
+++ b/src/Handlers/PredisHandler.php
@@ -62,15 +62,22 @@ public function pop(string $queue, array $priorities): ?QueueJob
         $now   = Time::now()->timestamp;
 
         foreach ($priorities as $priority) {
-            if ($tasks = $this->predis->zrangebyscore("queues:{$queue}:{$priority}", '-inf', $now, ['LIMIT' => [0, 1]])) {
-                if ($this->predis->zrem("queues:{$queue}:{$priority}", ...$tasks)) {
+            $tasks = $this->predis->zrangebyscore(
+                "queues:{$queue}:{$priority}",
+                '-inf',
+                $now,
+                ['LIMIT' => [0, 1]]
+            );
+            if ($tasks !== []) {
+                $removed = $this->predis->zrem("queues:{$queue}:{$priority}", ...$tasks);
+                if ($removed !== 0) {
                     break;
                 }
                 $tasks = [];
             }
         }
 
-        if (empty($tasks[0])) {
+        if ($tasks === []) {
             return null;
         }
 
@@ -93,7 +100,11 @@ public function later(QueueJob $queueJob, int $seconds): bool
         $queueJob->status       = Status::PENDING->value;
         $queueJob->available_at = Time::now()->addSeconds($seconds)->timestamp;
 
-        if ($result = $this->predis->zadd("queues:{$queueJob->queue}:{$queueJob->priority}", [json_encode($queueJob) => $queueJob->available_at->timestamp])) {
+        $result = $this->predis->zadd(
+            "queues:{$queueJob->queue}:{$queueJob->priority}",
+            [json_encode($queueJob) => $queueJob->available_at->timestamp]
+        );
+        if ($result !== 0) {
             $this->predis->hdel("queues:{$queueJob->queue}::reserved", [$queueJob->id]);
         }
 
@@ -131,14 +142,16 @@ public function done(QueueJob $queueJob, bool $keepJob): bool
     public function clear(?string $queue = null): bool
     {
         if ($queue !== null) {
-            if ($keys = $this->predis->keys("queues:{$queue}:*")) {
+            $keys = $this->predis->keys("queues:{$queue}:*");
+            if ($keys !== []) {
                 return $this->predis->del($keys) > 0;
             }
 
             return true;
         }
 
-        if ($keys = $this->predis->keys('queues:*')) {
+        $keys = $this->predis->keys('queues:*');
+        if ($keys !== []) {
             return $this->predis->del($keys) > 0;
         }
 
diff --git a/src/Handlers/RedisHandler.php b/src/Handlers/RedisHandler.php
index 3036893..64f5562 100644
--- a/src/Handlers/RedisHandler.php
+++ b/src/Handlers/RedisHandler.php
@@ -89,7 +89,7 @@ public function pop(string $queue, array $priorities): ?QueueJob
             }
         }
 
-        if (empty($tasks[0])) {
+        if ($tasks === []) {
             return null;
         }
 
@@ -114,7 +114,12 @@ public function later(QueueJob $queueJob, int $seconds): bool
         $queueJob->status       = Status::PENDING->value;
         $queueJob->available_at = Time::now()->addSeconds($seconds)->timestamp;
 
-        if ($result = (int) $this->redis->zAdd("queues:{$queueJob->queue}:{$queueJob->priority}", $queueJob->available_at->timestamp, json_encode($queueJob))) {
+        $result = (int) $this->redis->zAdd(
+            "queues:{$queueJob->queue}:{$queueJob->priority}",
+            $queueJob->available_at->timestamp,
+            json_encode($queueJob)
+        );
+        if ($result !== 0) {
             $this->redis->hDel("queues:{$queueJob->queue}::reserved", (string) $queueJob->id);
         }