std/package.d - better unittests

[Anonymous]

Looking through the std/package.d unittests, it seems too prone 
to mistakes. There is currently nothing in place to make sure 
that `import std` actually does import all of the modules in the 
standard library.

I threw together a quick unittest that checks to make sure that 
all standard library modules are imported by std/package.d: 
(diff) https://pastebin.com/v1EnyZ53 (warning: very 
hacked-together)

I ran it, and got these results:

std.typetuple is not imported in std.package.
std.xml is not imported in std.package.
std.outbuffer is not imported in std.package.

Is there a reason that these are not imported, or is it just 
accidental?

I think there should be an additional unittest added to 
std.package that checks like this to prevent mistakes when new 
modules are added to phobos.


Thoughts?