https://issues.dlang.org/show_bug.cgi?id=13454

          Issue ID: 13454
           Summary: Unit tests should be compiled in a module, where they
                    are declared
           Product: D
           Version: D1 & D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: performance
          Severity: normal
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: dfj1esp02@sneakemail.com

http://forum.dlang.org/post/luoc6f$2qcg$1@digitalmars.com
There's no way to disable unittests compiled as part of templates, instantiated
from another library.


Error:
---
template A(T)
{
  int a;
  unittest{ f(); }
}

version(unittest) void f(){}
---
If this module is compiled without unittests, `f` function will not be compiled, then if another module is compiled with unittests and instantiates the template, the template's unittest is compiled and it will link with `f` function, which wasn't compiled, so linking will fail? There will be no way to compile the importing module with unittests.


Performance:
---
import core.stdc.stdio:puts;
template A(T)
{
    shared int a;
    unittest { puts("test"); }
}

int main()
{
    A!(int).a=0;
    A!(long).a=0;
    return 0;
}
---
test
test
---
The same test was executed twice (for each instance of a template). It's questionable that duplicating tests for each instantiation of a template is intended.

--