[Syntax] Using php <= 7.3 syntaxes

src/AbstractSerializer.php

@@ -21,9 +21,9 @@
  */
 abstract class AbstractSerializer
 {
-    const CR  = "\r";
-    const EOL = "\r\n";
-    const LF  = "\n";
+    public const CR  = "\r";
+    public const EOL = "\r\n";
+    public const LF  = "\n";
 
     /**
      * Retrieve a single line from the stream.

src/Response.php

@@ -24,8 +24,8 @@ class Response implements ResponseInterface
 {
     use MessageTrait;
 
-    const MIN_STATUS_CODE_VALUE = 100;
-    const MAX_STATUS_CODE_VALUE = 599;
+    public const MIN_STATUS_CODE_VALUE = 100;
+    public const MAX_STATUS_CODE_VALUE = 599;
 
     /**
      * Map of standard HTTP status code/reason phrases

src/Response/JsonResponse.php

@@ -37,7 +37,7 @@ class JsonResponse extends Response
      *
      * @const int
      */
-    const DEFAULT_JSON_FLAGS = 79;
+    public const DEFAULT_JSON_FLAGS = 79;
 
     /**
      * @var mixed

src/Response/Serializer.php

@@ -94,6 +94,6 @@ private static function getStatusLine(StreamInterface $stream) : array
             throw Exception\SerializationException::forInvalidStatusLine();
         }
 
-        return [$matches['version'], (int) $matches['status'], isset($matches['reason']) ? $matches['reason'] : ''];
+        return [$matches['version'], (int) $matches['status'], $matches['reason'] ?? ''];
     }
 }

src/UploadedFile.php

@@ -32,7 +32,7 @@
 
 class UploadedFile implements UploadedFileInterface
 {
-    const ERROR_MESSAGES = [
+    public const ERROR_MESSAGES = [
         UPLOAD_ERR_OK         => 'There is no error, the file uploaded with success',
         UPLOAD_ERR_INI_SIZE   => 'The uploaded file exceeds the upload_max_filesize directive in php.ini',
         UPLOAD_ERR_FORM_SIZE  => 'The uploaded file exceeds the MAX_FILE_SIZE directive that was '

src/Uri.php

@@ -43,14 +43,14 @@ class Uri implements UriInterface
      *
      * @const string
      */
-    const CHAR_SUB_DELIMS = '!\$&\'\(\)\*\+,;=';
+    public const CHAR_SUB_DELIMS = '!\$&\'\(\)\*\+,;=';
 
     /**
      * Unreserved characters used in user info, paths, query strings, and fragments.
      *
      * @const string
      */
-    const CHAR_UNRESERVED = 'a-zA-Z0-9_\-\.~\pL';
+    public const CHAR_UNRESERVED = 'a-zA-Z0-9_\-\.~\pL';
 
     /**
      * @var int[] Array indexed by valid scheme names to their corresponding ports.
@@ -457,7 +457,7 @@ private function parseUri(string $uri) : void
         $this->scheme    = isset($parts['scheme']) ? $this->filterScheme($parts['scheme']) : '';
         $this->userInfo  = isset($parts['user']) ? $this->filterUserInfoPart($parts['user']) : '';
         $this->host      = isset($parts['host']) ? strtolower($parts['host']) : '';
-        $this->port      = isset($parts['port']) ? $parts['port'] : null;
+        $this->port      = $parts['port'] ?? null;
         $this->path      = isset($parts['path']) ? $this->filterPath($parts['path']) : '';
         $this->query     = isset($parts['query']) ? $this->filterQuery($parts['query']) : '';
         $this->fragment  = isset($parts['fragment']) ? $this->filterFragment($parts['fragment']) : '';