[patch] hashcache fixes

[Andrew Bennetts]

On Mon, Jul 10, 2006 at 04:59:05PM +1000, Andrew Bennetts wrote:
[...]
> Looking at the problem from a strict testability point of view, this suggests
> the code isn't factored well enough.  What if the _fingerprint function was a
> method of HashCache objects instead, so test cases can override it to return
> modified results -- e.g.:

It occurs to me that to completely factor out external stuff that we can't
control, the same principle applies to the use of time.time().  Hashcache could
have a "now" method that just does "return time.time()", and tests could
override it.  This way tests can completely control all the variables involved
in get_sha1, and thus test all the logic deterministically.

-Andrew.