[PATCH 2 of 3] context: override workingctx.hex() to avoid a crash

[Matt Mackall]

On Tue, 2015-06-16 at 00:26 +0900, Yuya Nishihara wrote:
> On Mon, 15 Jun 2015 00:28:58 -0400, Matt Harbison wrote:
> > # HG changeset patch
> > # User Matt Harbison <matt_harbison at yahoo.com>
> > # Date 1434333857 14400
> > #      Sun Jun 14 22:04:17 2015 -0400
> > # Node ID f5f5e4ae488d9cae8111e9a212f647ed1430a019
> > # Parent  9c738d2588313bb624465495a8923b293c45b999
> > context: override workingctx.hex() to avoid a crash
> > 
> > Since node is None for workingctx, it can't use the base class implementation of
> > 'hex(self.node())'.
> > 
> > It doesn't appear that there are any current callers of this, but there will be
> > when archive supports 'wdir()'.  Since 'hg id' prints "p1.node() + '+'" for a
> > dirty working copy, this does too.  That of course means that it isn't possible
> > to call 'bin(ctx.hex())', but that seems circuitous.  Having the '+' seems like
> > a useful distinction when building the .hg_archival.txt file.
> > 
> > diff --git a/mercurial/context.py b/mercurial/context.py
> > --- a/mercurial/context.py
> > +++ b/mercurial/context.py
> > @@ -1334,6 +1334,12 @@
> >      def __contains__(self, key):
> >          return self._repo.dirstate[key] not in "?r"
> >  
> > +    def hex(self):
> > +        hex = self.p1().hex()
> > +        if self.dirty():
> > +            hex += '+'
> > +        return hex
> 
> I won't argue, but I have to say it won't be so useful.

I think this is pretty iffy. We might want to instead do something
analogous to null and assign fff... to the working copy. If I were
smarter way back when, I might have made the scheme look like:

rev     hash
0       00000  <- null revision
1       ???    <- first revision
...     
maxint ffff   <- working copy

-- 
Mathematics is the supreme nostalgia of our time.