circular xs:import crashes scalaxb

[eed3si9n]

reported by Andreas Sewe.

steps

1. compile a schema with circular imports like DocBook.

problem

$ scalaxb -p:http://www.w3.org/1999/xlink=xlink= -p:http://docbook.org/ns/docbook=docbook assembly.xsd docbook.xsd xlink.xsd
java.lang.RuntimeException: Circular import: List(scalaxb.compiler.xsd.Driver$$anon$3@5de9ac4, scalaxb.compiler.xsd.Driver$$anon$3@5982bcde, scalaxb.compiler.xsd.Driver$$anon$3@163dc0bb)
    at scala.Predef$.error(Predef.scala:58)
    at scalaxb.compiler.Module$class.sortByDependency(Module.scala:135)
    at scalaxb.compiler.xsd.Driver.sortByDependency(Driver.scala:32)
    at scalaxb.compiler.Module$class.processReaders(Module.scala:87)
    at scalaxb.compiler.xsd.Driver.processReaders(Driver.scala:32)
    at scalaxb.compiler.Module$class.processFiles(Module.scala:63)
    at scalaxb.compiler.xsd.Driver.processFiles(Driver.scala:32)
    at scalaxb.compiler.Main$.start(Main.scala:84)
    at scalaxb.compiler.Main$.main(Main.scala:32)
    at scalaxb.compiler.Main.main(Main.scala)

expectation

XML Schema allows circular imports. Handle it.

[eed3si9n]

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