https://issues.dlang.org/show_bug.cgi?id=20911

          Issue ID: 20911
           Summary: Documentation for test/unit is non-existant
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

Looking at https://github.com/dlang/dmd/tree/master/test/unit:

1. No description of what it is, what it is for, etc.
2. No description of what the files are
3. No description of how to compile them (attempting to compile them just
produces lots of compile errors)
4. files like `frontend.d` do not have a SINGLE COMMENT in them
5. no `main` function anywhere

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