[PATCH 3 of 5] outgoing: add a 'missingroots' argument

[Pierre-Yves David]

On 08/14/2016 06:07 PM, Gregory Szorc wrote:
> On Thu, Aug 11, 2016 at 1:06 PM, Pierre-Yves David
> <pierre-yves.david at ens-lyon.org <mailto:pierre-yves.david at ens-lyon.org>>
> wrote:
>
>     # HG changeset patch
>     # User Pierre-Yves David <pierre-yves.david at ens-lyon.org
>     <mailto:pierre-yves.david at ens-lyon.org>>
>     # Date 1470774698 -7200
>     #      Tue Aug 09 22:31:38 2016 +0200
>     # Node ID 8c4fcb1244bdf79caadadc73fc1e489a160a07ec
>     # Parent  9ff7059253fd00094799f592462590cd837fb457
>     # EXP-Topic outgoing
>     outgoing: add a 'missingroots' argument
>
>     This argument can be used instead of 'commonheads' to determine the
>     'outgoing'
>     set. We remove the outgoingbetween function as its role can now be
>     handled by
>     'outgoing' itself.
>
>     I've thought of using an external function instead of making the
>     constructor
>     more complicated. However, there is low hanging fruit to improve the
>     current
>     code flow by storing some side products of the processing of
>     'missingroots'. So
>     in my opinion it make senses to add all this to the class.
>
>     diff -r 9ff7059253fd -r 8c4fcb1244bd mercurial/changegroup.py
>     --- a/mercurial/changegroup.py  Tue Aug 09 15:55:44 2016 +0200
>     +++ b/mercurial/changegroup.py  Tue Aug 09 22:31:38 2016 +0200
>     @@ -943,7 +943,7 @@ def changegroupsubset(repo, roots, heads
>          Another wrinkle is doing the reverse, figuring out which
>     changeset in
>          the changegroup a particular filenode or manifestnode belongs to.
>          """
>     -    outgoing = discovery.outgoingbetween(repo, roots, heads)
>     +    outgoing = discovery.outgoing(repo, missingroots=roots,
>     missingheads=heads)
>          bundler = getbundler(version, repo)
>          return getsubset(repo, outgoing, bundler, source)
>
>     diff -r 9ff7059253fd -r 8c4fcb1244bd mercurial/discovery.py
>     --- a/mercurial/discovery.py    Tue Aug 09 15:55:44 2016 +0200
>     +++ b/mercurial/discovery.py    Tue Aug 09 22:31:38 2016 +0200
>     @@ -76,11 +76,25 @@ class outgoing(object):
>          The sets are computed on demand from the heads, unless provided
>     upfront
>          by discovery.'''
>
>     -    def __init__(self, repo, commonheads=None, missingheads=None):
>     +    def __init__(self, repo, commonheads=None, missingheads=None,
>     +                 missingroots=None):
>     +        # at least one of them must not be set
>     +        assert None in (commonheads, missingroots)
>              cl = repo.changelog
>              if not missingheads:
>                  missingheads = cl.heads()
>     -        if not commonheads:
>     +        if missingroots:
>     +            discbases = []
>     +            for n in missingroots:
>     +                discbases.extend([p for p in cl.parents(n) if p !=
>     nullid])
>     +            # TODO remove call to nodesbetween.
>     +            # TODO populate attributes on outgoing instance instead
>     of setting
>     +            # discbases.
>     +            csets, roots, heads = cl.nodesbetween(missingroots,
>     missingheads)
>     +            included = set(csets)
>     +            missingheads = heads
>     +            commonheads = [n for n in discbases if n not in included]
>     +        elif not commonheads:
>                  commonheads = [nullid]
>              self.commonheads = commonheads
>              self.missingheads = missingheads
>     @@ -106,27 +120,6 @@ class outgoing(object):
>                  self._computecommonmissing()
>              return self._missing
>
>     -def outgoingbetween(repo, roots, heads):
>     -    """create an ``outgoing`` consisting of nodes between roots and
>     heads
>     -
>     -    The ``missing`` nodes will be descendants of any of the
>     ``roots`` and
>     -    ancestors of any of the ``heads``, both are which are defined
>     as a list
>     -    of binary nodes.
>     -    """
>     -    cl = repo.changelog
>     -    if not roots:
>     -        roots = [nullid]
>     -    discbases = []
>     -    for n in roots:
>     -        discbases.extend([p for p in cl.parents(n) if p != nullid])
>     -    # TODO remove call to nodesbetween.
>     -    # TODO populate attributes on outgoing instance instead of setting
>     -    # discbases.
>     -    csets, roots, heads = cl.nodesbetween(roots, heads)
>     -    included = set(csets)
>     -    discbases = [n for n in discbases if n not in included]
>     -    return outgoing(repo, discbases, heads)
>     -
>      def findcommonoutgoing(repo, other, onlyheads=None, force=False,
>                             commoninc=None, portable=False):
>          '''Return an outgoing instance to identify the nodes present in
>     repo but
>
>
> I'm not thrilled about the complexity of outgoing.__init__. Personally,
> I'd rather have a "dumb" container object that is populated by N
> specialized functions (like "outgoingbetween"). But that's just my style.

Next step after this is to move the complexe computation from __init__ 
to dedicated method and have the object computed other attributes on the 
fly when requested (as we do for other ones). This should trim the 
complexity of __init__ back to picking default value when needed. I 
think that would be fine. What do you think?

Cheers.

-- 
Pierre-Yves David