Add a SingleSelectSqlFinalizer that can take care of adding offset/li…

…mit as well as locking mode statements to a given SQL query.

Add a FinalizedSelectExecutor that executes given, finalized SQL statements.

lib/Doctrine/ORM/Query/Exec/FinalizedSelectExecutor.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\ORM\Query\Exec;
+
+use Doctrine\DBAL\Connection;
+use Doctrine\DBAL\Result;
+
+/**
+ * SQL executor for a given, final, single SELECT SQL query
+ */
+class FinalizedSelectExecutor extends AbstractSqlExecutor
+{
+    public function __construct(string $sql)
+    {
+        parent::__construct();
+
+        $this->sqlStatements = $sql;
+    }
+
+    public function execute(Connection $conn, array $params, array $types): Result
+    {
+        return $conn->executeQuery($this->getSqlStatements(), $params, $types, $this->queryCacheProfile);
+    }
+}

lib/Doctrine/ORM/Query/Exec/SingleSelectSqlFinalizer.php

@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\ORM\Query\Exec;
+
+use Doctrine\DBAL\LockMode;
+use Doctrine\ORM\Query;
+use Doctrine\ORM\Query\QueryException;
+
+/**
+ * SingleSelectSqlFinalizer finalizes a given SQL query by applying
+ * the query's firstResult/maxResult values as well as extra read lock/write lock
+ * statements, both through the platform-specific methods.
+ *
+ * The resulting, "finalized" SQL is passed to a FinalizedSelectExecutor.
+ */
+class SingleSelectSqlFinalizer implements SqlFinalizer
+{
+    /** @var string */
+    private $sql;
+
+    public function __construct(string $sql)
+    {
+        $this->sql = $sql;
+    }
+
+    /**
+     * @internal
+     *
+     * @psalm-internal Doctrine\ORM
+     *
+     * This method exists temporarily to support old SqlWalker interfaces.
+     */
+    public function finalizeSql(Query $query): string
+    {
+        $platform = $query->getEntityManager()->getConnection()->getDatabasePlatform();
+
+        $sql = $platform->modifyLimitQuery($this->sql, $query->getMaxResults(), $query->getFirstResult());
+
+        $lockMode = $query->getHint(Query::HINT_LOCK_MODE) ?: LockMode::NONE;
+
+        if ($lockMode !== LockMode::NONE && $lockMode !== LockMode::OPTIMISTIC && $lockMode !== LockMode::PESSIMISTIC_READ && $lockMode !== LockMode::PESSIMISTIC_WRITE) {
+            throw QueryException::invalidLockMode();
+        }
+
+        if ($lockMode === LockMode::PESSIMISTIC_READ) {
+            $sql .= ' ' . $platform->getReadLockSQL();
+        } elseif ($lockMode === LockMode::PESSIMISTIC_WRITE) {
+            $sql .= ' ' . $platform->getWriteLockSQL();
+        }
+
+        return $sql;
+    }
+
+    public function createExecutor(Query $query): AbstractSqlExecutor
+    {
+        return new FinalizedSelectExecutor($this->finalizeSql($query));
+    }
+}