Revert "fix: #3569316 Client connection () must be of type object, null given when deleting a node"

    foreach (array_reverse($this->stack()) as $id => $item) {

      $this->unpile($item->name, $id);

    }

    // Run post-transaction callbacks now (while Connection is still valid).

    // Prevents destructor-order bug: Connection::__destruct can run before

    // Transaction::__destruct, leaving PDO null when callbacks run.

    $this->processPostTransactionCallbacks();

  }

  /**

    $this->assertRowPresent('row');

  }

  /**

   * Tests post-transaction callback executes on "garbage collection".

   *

   * Simulate the end of a request by closing the connection and destroying

   * the transaction manually. The order matters for this test as the garbage

   * collection is unpredictable and could operate this way.

   */

  public function testPostTransactionsAlwaysExecutedBeforeConnectionIsDestroyed(): void {

    $transaction = $this->createRootTransaction('', FALSE);

    $this->connection->transactionManager()->addPostTransactionCallback([$this, 'rootTransactionCallback']);

    $this->insertRow('row');

    $this->assertNull($this->postTransactionCallbackAction);

    $this->assertRowAbsent('rtcCommit');

    Database::closeConnection();

    // @phpstan-ignore unset.possiblyHookedProperty

    unset($this->connection);

    unset($transaction);

    // Reopen the database connection so we can continue running assertions.

    $this->connection = Database::getConnection();

    // The post-transaction callback should now have inserted a 'rtcCommit'

    // row.

    $this->assertSame('rtcCommit', $this->postTransactionCallbackAction);

    $this->assertRowPresent('row');

    $this->assertRowPresent('rtcCommit');

  }

  /**

   * A post-transaction callback for testing purposes.

   */