[PATCH 4 of 8] transaction: avoid file stat ambiguity only for files in blacklist

[Yuya Nishihara]

On Sun, 02 Jul 2017 23:55:15 +0900, FUJIWARA Katsunori wrote:
> At Sun, 2 Jul 2017 23:06:04 +0900,
> Yuya Nishihara wrote:
> > 
> > On Fri, 30 Jun 2017 01:53:11 +0900, FUJIWARA Katsunori wrote:
> > > # HG changeset patch
> > > # User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
> > > # Date 1498754869 -32400
> > > #      Fri Jun 30 01:47:49 2017 +0900
> > > # Node ID d4d47784511456e6cf77b194822f23586e052312
> > > # Parent  9114ae36f40b733912705ef0bacb2961941f18d6
> > > transaction: avoid file stat ambiguity only for files in blacklist
> > 
> > > diff --git a/mercurial/transaction.py b/mercurial/transaction.py
> > > --- a/mercurial/transaction.py
> > > +++ b/mercurial/transaction.py
> > > @@ -44,11 +44,12 @@ def active(func):
> > >      return _active
> > >  
> > >  def _playback(journal, report, opener, vfsmap, entries, backupentries,
> > > -              unlink=True):
> > > +              unlink=True, noambigstatfiles=None):
> > >      for f, o, _ignore in entries:
> > >          if o or not unlink:
> > > +            checkambig = noambigstatfiles and (f, '') in noambigstatfiles
> > >              try:
> > > -                fp = opener(f, 'a', checkambig=True)
> > > +                fp = opener(f, 'a', checkambig=checkambig)
> > >                  fp.truncate(o)
> > >                  fp.close()
> > >              except IOError:
> > > @@ -101,7 +102,8 @@ def _playback(journal, report, opener, v
> > >  
> > >  class transaction(object):
> > >      def __init__(self, report, opener, vfsmap, journalname, undoname=None,
> > > -                 after=None, createmode=None, validator=None, releasefn=None):
> > > +                 after=None, createmode=None, validator=None, releasefn=None,
> > > +                 noambigstatfiles=None):
> > >          """Begin a new transaction
> > >  
> > >          Begins a new transaction that allows rolling back writes in the event of
> > > @@ -110,6 +112,10 @@ class transaction(object):
> > >          * `after`: called after the transaction has been committed
> > >          * `createmode`: the mode of the journal file that will be created
> > >          * `releasefn`: called after releasing (with transaction and result)
> > > +
> > > +        `noambigstatfiles` is a set of (path, vfs-location) tuples,
> > > +        which determine whether file stat ambiguity should be avoided
> > > +        for corresponded files.
> > 
> > IIUC, this is a set of files that could get ambiguous, but "noambig" semed to
> > say the opposite.
> 
> I named this as "(caller requires) no ambiguity of stat for files (in
> this set)". But I agree that this name is not understandable :-)
> 
> How about "avoidambigfiles" or "avoidstatambigfiles" ? or any ideas ?

or "checkambigfiles" as the boolean flag is called as "checkambig"? I don't
know which is preferable, but any of these seem better than "noambig".