expose class declared in unittest

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On Wednesday, 25 June 2014 at 20:17:35 UTC, rcor wrote:
> I'm trying to create a set of utility functions that cache 
> objects of various types loaded from json files, but having 
> trouble testing it. One function I'd like to test uses new to 
> instantiate an object based on a compile-time parameter:
>
> void loadDataFile(T)(string filename) {
> ...
>   T obj = new T(name, value);
> ...
> }
>
> When testing, I try to create a dummy class to test that data 
> can be written and read properly:
>
> unittest {
>   class Dummy { ... }
>   ... write some json to a tempfile ...
>   loadDataFile!Dummy(tempfile_path);
>   ... verify loaded data ...
> }
>
> When running the test, I get the error "outer function context 
> of util.jsondata.__unittestL31_1 is needed to 'new' nested 
> class util.jsondata.__unittestL31_1."
> So it seems that a class nested in a unittest can't be 'newed' 
> outside of the test.
>
> The test runs if I declare Dummy outside of the unittest, but I 
> don't want it to exist outside of the test. I could import 
> modules containing some of the classes that I will actually be 
> loading with this, but I feel like the unittest shouldn't 
> depend on those, as its designed to work with arbitrary 
> classes. Any suggestions would be appreciated.

I don't completely understand your problem, but have you tried 
marking the class as static?

static class Dummy { ... }