Fix code style

Author: dmitry-ivanov

src/classes/System/OS.php

@@ -6,6 +6,6 @@ class OS
 {
     public static function isWindows()
     {
-        return (strtoupper(substr(php_uname(), 0, 7)) === 'WINDOWS');
+        return strtoupper(substr(php_uname(), 0, 7)) === 'WINDOWS';
     }
 }

src/db.php

@@ -9,7 +9,7 @@ function db_is_sqlite()
         $connection = DB::getDefaultConnection();
         $driver = Config::get("database.connections.{$connection}.driver");
 
-        return ($driver == 'sqlite');
+        return $driver === 'sqlite';
     }
 }
 
@@ -19,7 +19,7 @@ function db_is_mysql()
         $connection = DB::getDefaultConnection();
         $driver = Config::get("database.connections.{$connection}.driver");
 
-        return ($driver == 'mysql');
+        return $driver === 'mysql';
     }
 }
 
@@ -35,6 +35,6 @@ function db_mysql_now()
     function db_mysql_variable($name)
     {
         $result = (array) DB::selectOne('show variables where variable_name = ?', [$name]);
-        return (isset($result['Value']) ? $result['Value'] : false);
+        return isset($result['Value']) ? $result['Value'] : false;
     }
 }

src/json.php

@@ -12,6 +12,6 @@ function is_json($string, $return = false)
             return false;
         }
 
-        return ($return ? $decoded : true);
+        return $return ? $decoded : true;
     }
 }