Introduce a null SQL logger

lib/Doctrine/DBAL/Configuration.php

@@ -3,6 +3,7 @@
 namespace Doctrine\DBAL;
 
 use Doctrine\Common\Cache\Cache;
+use Doctrine\DBAL\Logging\NullLogger;
 use Doctrine\DBAL\Logging\SQLLogger;
 use Doctrine\DBAL\Schema\AbstractAsset;
 use function preg_match;
@@ -35,12 +36,14 @@ class Configuration
 
     /**
      * Gets the SQL logger that is used.
-     *
-     * @return SQLLogger|null
      */
-    public function getSQLLogger()
+    public function getSQLLogger() : SQLLogger
     {
-        return $this->_attributes['sqlLogger'] ?? null;
+        if (! isset($this->_attributes['sqlLogger'])) {
+            $this->_attributes['sqlLogger'] = new NullLogger();
+        }
+
+        return $this->_attributes['sqlLogger'];
     }
 
     /**

lib/Doctrine/DBAL/Connection.php

@@ -889,9 +889,7 @@ class Connection implements DriverConnection
         $this->connect();
 
         $logger = $this->_config->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($query, $params, $types);
-        }
 
         try {
             if ($params) {
@@ -913,9 +911,7 @@ class Connection implements DriverConnection
 
         $stmt->setFetchMode($this->defaultFetchMode);
 
-        if ($logger) {
         $logger->stopQuery();
-        }
 
         return $stmt;
     }
@@ -1002,9 +998,7 @@ class Connection implements DriverConnection
         $args = func_get_args();
 
         $logger = $this->_config->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($args[0]);
-        }
 
         try {
             $statement = $this->_conn->query(...$args);
@@ -1014,9 +1008,7 @@ class Connection implements DriverConnection
 
         $statement->setFetchMode($this->defaultFetchMode);
 
-        if ($logger) {
         $logger->stopQuery();
-        }
 
         return $statement;
     }
@@ -1040,9 +1032,7 @@ class Connection implements DriverConnection
         $this->connect();
 
         $logger = $this->_config->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($query, $params, $types);
-        }
 
         try {
             if ($params) {
@@ -1063,9 +1053,7 @@ class Connection implements DriverConnection
             throw DBALException::driverExceptionDuringQuery($this->_driver, $ex, $query, $this->resolveParams($params, $types));
         }
 
-        if ($logger) {
         $logger->stopQuery();
-        }
 
         return $result;
     }
@@ -1084,9 +1072,7 @@ class Connection implements DriverConnection
         $this->connect();
 
         $logger = $this->_config->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($statement);
-        }
 
         try {
             $result = $this->_conn->exec($statement);
@@ -1094,9 +1080,7 @@ class Connection implements DriverConnection
             throw DBALException::driverExceptionDuringQuery($this->_driver, $ex, $statement);
         }
 
-        if ($logger) {
         $logger->stopQuery();
-        }
 
         return $result;
     }
@@ -1240,23 +1224,15 @@ class Connection implements DriverConnection
         $logger = $this->_config->getSQLLogger();
 
         if ($this->transactionNestingLevel === 1) {
-            if ($logger) {
             $logger->startQuery('"START TRANSACTION"');
-            }
             $this->_conn->beginTransaction();
-            if ($logger) {
             $logger->stopQuery();
-            }
         } elseif ($this->nestTransactionsWithSavepoints) {
-            if ($logger) {
             $logger->startQuery('"SAVEPOINT"');
-            }
             $this->createSavepoint($this->_getNestedTransactionSavePointName());
-            if ($logger) {
             $logger->stopQuery();
         }
     }
-    }
 
     /**
      * Commits the current transaction.
@@ -1280,22 +1256,14 @@ class Connection implements DriverConnection
         $logger = $this->_config->getSQLLogger();
 
         if ($this->transactionNestingLevel === 1) {
-            if ($logger) {
             $logger->startQuery('"COMMIT"');
-            }
             $this->_conn->commit();
-            if ($logger) {
             $logger->stopQuery();
-            }
         } elseif ($this->nestTransactionsWithSavepoints) {
-            if ($logger) {
             $logger->startQuery('"RELEASE SAVEPOINT"');
-            }
             $this->releaseSavepoint($this->_getNestedTransactionSavePointName());
-            if ($logger) {
             $logger->stopQuery();
         }
-        }
 
         --$this->transactionNestingLevel;
 
@@ -1340,28 +1308,20 @@ class Connection implements DriverConnection
         $logger = $this->_config->getSQLLogger();
 
         if ($this->transactionNestingLevel === 1) {
-            if ($logger) {
             $logger->startQuery('"ROLLBACK"');
-            }
             $this->transactionNestingLevel = 0;
             $this->_conn->rollBack();
             $this->isRollbackOnly = false;
-            if ($logger) {
             $logger->stopQuery();
-            }
 
             if ($this->autoCommit === false) {
                 $this->beginTransaction();
             }
         } elseif ($this->nestTransactionsWithSavepoints) {
-            if ($logger) {
             $logger->startQuery('"ROLLBACK TO SAVEPOINT"');
-            }
             $this->rollbackSavepoint($this->_getNestedTransactionSavePointName());
             --$this->transactionNestingLevel;
-            if ($logger) {
             $logger->stopQuery();
-            }
         } else {
             $this->isRollbackOnly = true;
             --$this->transactionNestingLevel;

lib/Doctrine/DBAL/Connections/MasterSlaveConnection.php

@@ -348,15 +348,11 @@ class MasterSlaveConnection extends Connection
         $args = func_get_args();
 
         $logger = $this->getConfiguration()->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($args[0]);
-        }
 
         $statement = $this->_conn->query(...$args);
 
-        if ($logger) {
         $logger->stopQuery();
-        }
 
         return $statement;
     }

lib/Doctrine/DBAL/Logging/NullLogger.php

+<?php
+
+namespace Doctrine\DBAL\Logging;
+
+/**
+ * A SQL logger that does nothing.
+ */
+class NullLogger implements SQLLogger
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function startQuery($sql, array $params = null, array $types = null)
+    {
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function stopQuery()
+    {
+    }
+}

lib/Doctrine/DBAL/Statement.php

@@ -144,16 +144,12 @@ class Statement implements IteratorAggregate, DriverStatement
         }
 
         $logger = $this->conn->getConfiguration()->getSQLLogger();
-        if ($logger) {
         $logger->startQuery($this->sql, $this->params, $this->types);
-        }
 
         try {
             $stmt = $this->stmt->execute($params);
         } catch (Throwable $ex) {
-            if ($logger) {
             $logger->stopQuery();
-            }
             throw DBALException::driverExceptionDuringQuery(
                 $this->conn->getDriver(),
                 $ex,
@@ -162,9 +158,7 @@ class Statement implements IteratorAggregate, DriverStatement
             );
         }
 
-        if ($logger) {
         $logger->stopQuery();
-        }
         $this->params = [];
         $this->types  = [];