createCustomFields example

static::assertFalse($this->columnExists($con));

        $m = new Migration1681382023AddCustomFieldAllowCartExpose();
        $m->update($con);

        static::assertTrue($this->columnExists($con));

        $con->setNestTransactionsWithSavepoints(true);
        $con->beginTransaction();

        $this->createCustomFields();
        $this->createRule();

        static::assertEquals(['0', '0', '0'], $this->getExposeSettings($con));

        $m->update($con);

        static::assertEquals(['1', '0', '1'], $this->getExposeSettings($con));

        $con->rollBack();
    }