DOMException when using two "ditavalref"'s on first level in map

Reported here:

https://groups.yahoo.com/neo/groups/dita-users/conversations/messages/43072

I’m attaching a sample project:

two-ditavalref-map.zip

There are two ditaval files referenced on the first DITA Map level like:

<map>
  <ditavalref href="ditavals/AWS.ditaval"/>
  <ditavalref href="ditavals/LINUX.ditaval"/>

I can reproduce problem with both DITA OT 2.x and 3.x:

BUILD FAILED
C:\Users\radu_coravu\Desktop\DITA OT newest\dita-ot-3.0.1\build.xml:45: The following error occurred     while executing this line:
C:\Users\radu_coravu\Desktop\DITA OT newest\dita-ot-3.0.1\plugins\org.dita.base\build_preprocess2.xml:110: org.w3c.dom.DOMException: HIERARCHY_REQUEST_ERR: An attempt was made to insert a node where it is not permitted.
at org.apache.xerces.dom.CoreDocumentImpl.insertBefore(Unknown Source)
at org.apache.xerces.dom.NodeImpl.appendChild(Unknown Source)
at org.dita.dost.module.filter.MapBranchFilterModule.splitBranches(MapBranchFilterModule.java:326)
at org.dita.dost.module.filter.MapBranchFilterModule.processMap(MapBranchFilterModule.java:111)
at org.dita.dost.module.filter.MapBranchFilterModule.execute(MapBranchFilterModule.java:78)
at org.dita.dost.ant.ExtensibleAntInvoker.execute(ExtensibleAntInvoker.java:163)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:293)
at sun.reflect.GeneratedMethodAccessor6.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

[robander]

Right, it is murky, and I’m not sure it can be fully handled (correctly) without larger changes to the processing pipeline.

Of course, using more than one ditavalref at the start of a map has other issues too. For example if you do it with bookmap (using the proposed DITA 2.0 model), you can end up with two separate sequences of [front matter, chapters, back matter].

I think the best fix here might be:

• Implement the solution I suggested above
• If relationship tables + key scopes do not work for some cases (they might, I’m not sure), then try and work out a design with #2147)
• Advise that if you’re trying to use ditavalref on the root map, you should take care; it may not be the most logical way to publish information anyway, due to the issues that can come up

[raducoravu]

Problem can still be reproduced with latest DITA OT code.