[PATCH 1 of 6] dirstate: make dirstate.write() callers pass repo object to it

[FUJIWARA Katsunori]

At Thu, 15 Oct 2015 15:37:48 -0500,
Matt Mackall wrote:
> 
> On Thu, 2015-10-15 at 20:40 +0100, Pierre-Yves David wrote:
> > 
> > On 10/15/2015 08:37 PM, Matt Mackall wrote:
> > > On Thu, 2015-10-15 at 02:35 +0900, FUJIWARA Katsunori wrote:
> > >> # HG changeset patch
> > >> # User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
> > >> # Date 1444843899 -32400
> > >> #      Thu Oct 15 02:31:39 2015 +0900
> > >> # Node ID 59a9e52b17e1af3f69b6c9472c9c10a6b00d9b24
> > >> # Parent  79d86ab65c9def3fdd65ec972bc5fa89688a19ff
> > >> dirstate: make dirstate.write() callers pass repo object to it
> > >>
> > >> Now, 'dirstate.write(repo)' delays writing in-memory changes out, if
> > >> any transaction is running.
> > >
> > > I guess I haven't been paying close enough attention to this as I didn't
> > > notice the patch that actually introduced this parameter.
> > >
> > > We should never pass a repo object to dirstate. It's a layering
> > > violation that we've carefully avoided for 10 years and makes it way too
> > > easy to get dirstate.py more entangled with upper levels that it has no
> > > business knowing about.
> > >
> > > Passing a transaction object by itself is ok, as it's a much lower level
> > > object that dirstate has perfectly good reasons to know about.
> 
> Here I heartily approve the use of transactions in dirstate.
> 
> > replacing
> >    dirstate.write(repo)
> > with
> >    dirstate.write(repo.currenttransaction())
> > 
> > will most probably fit our needs here.
> > 
> > > Similar concerns exist for passing a repo object to a ui, another
> > > situation we've been carefully avoiding since the beginning of time.
> > > We definitely do not want ui objects poking at repo objects. They
> > > probably shouldn't have code specific to pending transactions on general
> > > principle either.
> 
> And here I say that -ui- objects (infected later in this series) should
> not know about transactions... because they're concerned only with ui
> issues and blissfully unaware of how repos and revlogs and such work.
> 
> > I'm not sure about what you mean with that last sentence, but the 
> > dirstate -must- have some collaboration with the transaction. The lack 
> > of it have been biting us for the past x years.
> 
> I hope that clears it up.

Thank you for your suggestions, Matt and Pierre-Yves.

I'll post revised series with patches to fix some layering violation
already introduced into main hg repository.


> -- 
> Mathematics is the supreme nostalgia of our time.
> 
> 

----------------------------------------------------------------------
[FUJIWARA Katsunori]                             foozy at lares.dti.ne.jp