1 # narrowrevlog.py - revlog storing irrelevant nodes as "ellipsis" nodes

     2 #

     3 # Copyright 2017 Google, Inc.

     4 #

     5 # This software may be used and distributed according to the terms of the

     6 # GNU General Public License version 2 or any later version.

     7 

     8 from __future__ import absolute_import

     9 

    10 from mercurial import (

    11    revlog,

    12    util,

    13 )

    14 

    15 def readtransform(self, text):

    16     return text, False

    17 

    18 def writetransform(self, text):

    19     return text, False

    20 

    21 def rawtransform(self, text):

    22     return False

    23 

    24 revlog.addflagprocessor(revlog.REVIDX_ELLIPSIS,

    25                         (readtransform, writetransform, rawtransform))

    26 

    27 def setup():

    28     # We just wanted to add the flag processor, which is done at module

    29     # load time.

    30     pass

    31 

    32 def makenarrowfilelog(fl, narrowmatch):

    33     class narrowfilelog(fl.__class__):

    34         def renamed(self, node):

    35             # Renames that come from outside the narrowspec are

    36             # problematic at least for git-diffs, because we lack the

    37             # base text for the rename. This logic was introduced in

    38             # 3cd72b1 of narrowhg (authored by martinvonz, reviewed by

    39             # adgar), but that revision doesn't have any additional

    40             # commentary on what problems we can encounter.

    41             m = super(narrowfilelog, self).renamed(node)

    42             if m and not narrowmatch(m[0]):

    43                 return None

    44             return m

    45 

    46         def size(self, rev):

    47             # We take advantage of the fact that remotefilelog

    48             # lacks a node() method to just skip the

    49             # rename-checking logic when on remotefilelog. This

    50             # might be incorrect on other non-revlog-based storage

    51             # engines, but for now this seems to be fine.

    52             #

    53             # TODO: when remotefilelog is in core, improve this to

    54             # explicitly look for remotefilelog instead of cheating

    55             # with a hasattr check.

    56             if util.safehasattr(self, 'node'):

    57                 node = self.node(rev)

    58                 # Because renamed() is overridden above to

    59                 # sometimes return None even if there is metadata

    60                 # in the revlog, size can be incorrect for

    61                 # copies/renames, so we need to make sure we call

    62                 # the super class's implementation of renamed()

    63                 # for the purpose of size calculation.

    64                 if super(narrowfilelog, self).renamed(node):

    65                     return len(self.read(node))

    66             return super(narrowfilelog, self).size(rev)

    67 

    68         def cmp(self, node, text):

    69             different = super(narrowfilelog, self).cmp(node, text)

    70             if different:

    71                 # Similar to size() above, if the file was copied from

    72                 # a file outside the narrowspec, the super class's

    73                 # would have returned True because we tricked it into

    74                 # thinking that the file was not renamed.

    75                 if super(narrowfilelog, self).renamed(node):

    76                     t2 = self.read(node)

    77                     return t2 != text

    78             return different

    79 

    80     fl.__class__ = narrowfilelog