std.path review: update

[Lars T. Kyllingstad]

On Sun, 17 Jul 2011 22:38:43 -0700, Jonathan M Davis wrote:

> On Sunday 17 July 2011 22:08:27 Brian Schott wrote:
>> The documentation comments for driveName say that the return value will
>> be an empty string in some circumstances, but the code and unit tests
>> both say that the behavior is to return null.
> 
> The fun part with that is that "" == null and a null string is empty per
> std.array.empty, so it _is_ the empty string. The only difference is
> that "" !is null. So, if the function says that it returns null, then it
> needs to return null. Since it says that it returns the empty string, it
> could return either.
> 
> Now, in spite of all that, there's still a problem since the tests
> verify that the return value is null, not empty. Either the
> documentation should say that it returns null, or the tests should be
> checking for empty, not null. But still, the documentation isn't
> incorrect. Are the tests are perfectly valid, but they really shouldn't
> be testing for is null instead of empty when the function is supposed to
> return empty.

Pending a decision on the null vs. empty issue, I have now standardised 
on using empty() for testing whether functions return empty strings.

-Lars