comparison mercurial/utils/storageutil.py @ 40007:1470183068b8

storageutil: invert logic of file data comparison

IMO things make more sense when the function is explicitly a test
for file data equivalence.

Not bothering with API since the function was introduced by the
previous commit.

Differential Revision: https://phab.mercurial-scm.org/D4802

40006:422beffd71ba

    if meta and b'copy' in meta and b'copyrev' in meta:
        return meta[b'copy'], bin(meta[b'copyrev'])

    return False

def filerevisiondifferent(store, node, filedata):
    """Determines whether file data is equivalent to a stored node."""

    if filedata.startswith(b'\x01\n'):
        revisiontext = b'\x01\n\x01\n' + filedata
    else:
        revisiontext = filedata

    p1, p2 = store.parents(node)

    computednode = hashrevisionsha1(revisiontext, p1, p2)

    if computednode == node:
        return False

    # Censored files compare against the empty file.
    if store.iscensored(store.rev(node)):
        return filedata != b''

    # Renaming a file produces a different hash, even if the data
    # remains unchanged. Check if that's the case.
    if store.renamed(node):
        return store.read(node) != filedata

    return True

def iterrevs(storelen, start=0, stop=None):
    """Iterate over revision numbers in a store."""
    step = 1

40007:1470183068b8

    if meta and b'copy' in meta and b'copyrev' in meta:
        return meta[b'copy'], bin(meta[b'copyrev'])

    return False

def filedataequivalent(store, node, filedata):
    """Determines whether file data is equivalent to a stored node.

    Returns True if the passed file data would hash to the same value
    as a stored revision and False otherwise.

    When a stored revision is censored, filedata must be empty to have
    equivalence.

    When a stored revision has copy metadata, it is ignored as part
    of the compare.
    """

    if filedata.startswith(b'\x01\n'):
        revisiontext = b'\x01\n\x01\n' + filedata
    else:
        revisiontext = filedata

    p1, p2 = store.parents(node)

    computednode = hashrevisionsha1(revisiontext, p1, p2)

    if computednode == node:
        return True

    # Censored files compare against the empty file.
    if store.iscensored(store.rev(node)):
        return filedata == b''

    # Renaming a file produces a different hash, even if the data
    # remains unchanged. Check if that's the case.
    if store.renamed(node):
        return store.read(node) == filedata

    return False

def iterrevs(storelen, start=0, stop=None):
    """Iterate over revision numbers in a store."""
    step = 1