[PATCH 3 of 6] revlog: add support for 'original text' to addrevision and addgroup

[Matt Mackall]

On Mon, 2011-02-07 at 12:29 +0100, Sune Foldager wrote:
> On 01-02-2011 00:43, Matt Mackall wrote:
> > On Mon, 2011-01-31 at 11:21 +0100, Sune Foldager wrote:
> >> diff --git a/mercurial/revlog.py b/mercurial/revlog.py
> >> --- a/mercurial/revlog.py
> >> +++ b/mercurial/revlog.py
> >> @@ -923,7 +923,8 @@
> >>           tr.replace(self.indexfile, trindex * self._io.size)
> >>           self._chunkclear()
> >>
> >> -    def addrevision(self, text, transaction, link, p1, p2, cachedelta=None):
> >> +    def addrevision(self, text, transaction, link, p1, p2, cachedelta=None,
> >> +                    origtext=None):
> >
> > I think this is not the ideal interface.
> 
> Me neither.. I don't really like it too much.
> 
> > This appears to be motivated by the need to calculate the hash based on
> > the known text. But wouldn't it be better to factor out hash calculation
> > (already done!), then have filelog pass the hash in?
> 
> Unfortunately, the origtext is also needed for caching purposes (in 
> _addrevision), unless we, e.g., were to decide to not cache when this 
> feature is invoked. I am not sure about the implications of doing that 
> right now. Ideas?

Actually, that's trivial to work around - just have filelog update the
cache itself.

We also we want origtext for storing a proper length. But as it turns
out, this has long been slightly broken for renamed revisions.

What's most ugly here is passing in the text -three- different ways
(text, origtext, cachedelta). It seems like we should be able to break
this into a few layers, but I'm not sure how yet.

-- 
Mathematics is the supreme nostalgia of our time.