IS_REQUIRED error on Migration from Magento 1.9.2.2 to 2.2.6

Question

I'm trying some dry run to migrate data from Magento 1.9.2.2 to 2.2.6. After some adjustment, I'm stuck on the following error

[2018-10-28 14:57:56][INFO][mode: data][stage: data migration][step: Map Step]: started
26% [=======>--------------------] Remaining Time: 2 mins
[2018-10-28 14:58:59][ERROR]: Record structure does not contain field is_required

  [Migration\Exception]
  Data Migration failed

In map-eav xml there is a rule to transform it

    <transform>
        <field>eav_attribute.is_required</field>
        <handler class="\Migration\Handler\GetDestinationValue" />
    </transform>

but I don't know where to check and how to go on.

Answer 1

I solved with this fix

There are some files to upgrade.