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Tests may exist that cannot be included in the Daffodil repo, usually because of size or privacy concerns. However, it is still desirable to build and run the tests as if they were part of the normal sbt build/test process. The Daffodil build system provides a way to do this, using the daffodil-extra directory. First, create a directory containing tests using the SBT Directory Structure (you really only need src/test, and you do not need to create any sbt definition files, like build.sbt). Once this is created, add a symlink from the daffodil-extra directory to the root of your test directory:
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