comparison hgext/absorb.py @ 46780:6266d19556ad

node: introduce nodeconstants class

In preparing for moving from SHA1 hashes to a modern hash function,
place nullid and other constant magic vules in a class. Provide the
active set of constants in the repository and push it down. Provide
nullid directly in strategic places like the repository as it is
accessed very often. This changeset introduces the API change, but not
the mechanical replacement of the node.py attributes itself.

Differential Revision: https://phab.mercurial-scm.org/D9750

46779:49fd21f32695

class emptyfilecontext(object):
    """minimal filecontext representing an empty file"""

    def data(self):
        return b''

    def node(self):
        return nullid

    if pctx is not None:  # need an extra immutable fctx
        if path in pctx:
            fctxs.append(pctx[path])
        else:
            fctxs.append(emptyfilecontext())

    fctxs.reverse()
    # note: we rely on a property of hg: filerev is not reused for linear
    # history. i.e. it's impossible to have:
    #   changelog:  4----5----6 (linear, no merges)

46780:6266d19556ad

class emptyfilecontext(object):
    """minimal filecontext representing an empty file"""

    def __init__(self, repo):
        self._repo = repo

    def data(self):
        return b''

    def node(self):
        return nullid

    if pctx is not None:  # need an extra immutable fctx
        if path in pctx:
            fctxs.append(pctx[path])
        else:
            fctxs.append(emptyfilecontext(pctx.repo()))

    fctxs.reverse()
    # note: we rely on a property of hg: filerev is not reused for linear
    # history. i.e. it's impossible to have:
    #   changelog:  4----5----6 (linear, no merges)