BIND 10 #2292: eliminate const_cast from domaintree.h

[BIND 10 Development]

#2292: eliminate const_cast from domaintree.h
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                   Reporter:         |                 Owner:  jinmei
  jinmei                             |                Status:  reviewing
                       Type:         |             Milestone:
  defect                             |  Sprint-20121009
                   Priority:         |            Resolution:
  medium                             |             Sensitive:  0
                  Component:  data   |           Sub-Project:  DNS
  source                             |  Estimated Difficulty:  4
                   Keywords:         |           Total Hours:  0
            Defect Severity:  N/A    |
Feature Depending on Ticket:         |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Changes (by vorner):

 * owner:  vorner => jinmei


Comment:

 Hello

 I fixed the three small issues. But about this one, I have a problem
 understanding how you mean it.
 Replying to [comment:10 jinmei]:
 > I'm afraid we cannot simply remove all of these tests.  Things like
 > loadRRSIGsRdataMixedCoveredTypes() or addOutOfZoneThrows() still seem
 > to be necessary (or at least they cannot be removed due to this
 > ticket).  Also, we need *some* interface to add a particular RRset to
 > an existing zone anyway in order to support incremental updates after
 > ixfr or DDNS.
 >
 > #2268 revised the load/add interface quite substantially, so maybe we
 > merge this branch with #2268, and update some of these tests using the
 > revised add interface while keeping the constness of the domain tree
 > interface?

 Keeping the `add()` method seems to be a mutually exclusive requirement
 for the
 find to return immutable nodes, at least without cheating. If we have
 immutable
 node, we get only immutable ZoneData and therefore can't modify it to add
 another RRset.

 Also, I thought the incremental updates would happen inside the memory
 manager
 thing, which probably will look at the data in a different way. Therefore
 it
 might be premature to do some cheating because of add() that we may not
 need in
 the end.

 Maybe the tests could be reconstructed without using add at all, just by
 providing the right iterator, or something.

 Thank you

-- 
Ticket URL: <http://bind10.isc.org/ticket/2292#comment:12>
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