Add a test case for #234

[tribbloid]

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[tribbloid]

This is the error, did you see the following 3 lines?

    illTyped("""implicitly[TestRequireMsg]""","Testing 123")
    illTyped("implicitly[Set[TestFoo.FF[Int]]]", "Testing 123")
    illTyped("""implicitly[Set[Int]]""","could not find implicit value.*")

It appears that only the second line triggers the error, the first line behave completely as expected. I wonder if this could give us a cue?