Use coalesce operator (#982)

* Use coalesce operator

* Use coalesce operator

* Use coalesce operator

* Use coalesce operator

src/Monolog/ErrorHandler.php

@@ -175,7 +175,7 @@ class ErrorHandler
 
         // fatal error codes are ignored if a fatal error handler is present as well to avoid duplicate log entries
         if (!$this->hasFatalErrorHandler || !in_array($code, self::$fatalErrors, true)) {
-            $level = isset($this->errorLevelMap[$code]) ? $this->errorLevelMap[$code] : LogLevel::CRITICAL;
+            $level = $this->errorLevelMap[$code] ?? LogLevel::CRITICAL;
             $this->logger->log($level, self::codeToString($code).': '.$message, ['code' => $code, 'message' => $message, 'file' => $file, 'line' => $line]);
         }
 

src/Monolog/Handler/ChromePHPHandler.php

@@ -132,7 +132,7 @@ class ChromePHPHandler extends AbstractProcessingHandler
                 return;
             }
 
-            self::$json['request_uri'] = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : '';
+            self::$json['request_uri'] = $_SERVER['REQUEST_URI'] ?? '';
         }
 
         $json = @json_encode(self::$json);

src/Monolog/Handler/PHPConsoleHandler.php

@@ -203,10 +203,10 @@ class PHPConsoleHandler extends AbstractProcessingHandler
         $context = $record['context'];
 
         $this->connector->getErrorsDispatcher()->dispatchError(
-            isset($context['code']) ? $context['code'] : null,
-            isset($context['message']) ? $context['message'] : $record['message'],
-            isset($context['file']) ? $context['file'] : null,
-            isset($context['line']) ? $context['line'] : null,
+            $context['code'] ?? null,
+            $context['message'] ?? $record['message'],
+            $context['file'] ?? null,
+            $context['line'] ?? null,
             $this->options['classesPartialsTraceIgnore']
         );
     }

src/Monolog/Processor/WebProcessor.php

@@ -88,7 +88,7 @@ class WebProcessor
     private function appendExtraFields(array $extra): array
     {
         foreach ($this->extraFields as $extraName => $serverName) {
-            $extra[$extraName] = isset($this->serverData[$serverName]) ? $this->serverData[$serverName] : null;
+            $extra[$extraName] = $this->serverData[$serverName] ?? null;
         }
 
         if (isset($this->serverData['UNIQUE_ID'])) {