mercurial/cffi/mpatch.py

test-check-py3-compat: exclude thirdparty and cffi which are known to fail

Otherwise the following errors would be spilled out:

  mercurial/cffi/bdiff.py: error importing: <ImportError> cannot import
  name '_bdiff' (error at bdiff.py:*)
  mercurial/cffi/bdiffbuild.py: error importing: <ModuleNotFoundError> No
  module named 'cffi' (error at bdiffbuild.py:*)
  mercurial/cffi/mpatch.py: error importing: <ImportError> cannot import
  name '_mpatch' (error at mpatch.py:*)
  mercurial/cffi/mpatchbuild.py: error importing: <ModuleNotFoundError> No
  module named 'cffi' (error at mpatchbuild.py:*)
  mercurial/cffi/osutilbuild.py: error importing: <ModuleNotFoundError> No
  module named 'cffi' (error at osutilbuild.py:*)
  mercurial/thirdparty/concurrent/futures/_base.py: invalid syntax: invalid
  syntax (<unknown>, line *)
  mercurial/thirdparty/concurrent/futures/process.py: error importing:
  <SyntaxError> invalid syntax (_base.py, line 416) (error at __init__.py:*)
  mercurial/thirdparty/concurrent/futures/thread.py: error importing:
  <SyntaxError> invalid syntax (_base.py, line 416) (error at __init__.py:*)
  mercurial/thirdparty/zope/interface/_flatten.py: error importing:
  <ImportError> cannot import name 'Declaration' (error at _flatten.py:*)

Some of them can be suppressed by building cffi modules for example, but
I don't think it's worth keeping these modules covered by the compatibility
checker.

# mpatch.py - CFFI implementation of mpatch.c
#
# Copyright 2016 Maciej Fijalkowski <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from ..pure.mpatch import *
from ..pure.mpatch import mpatchError  # silence pyflakes
from . import _mpatch

ffi = _mpatch.ffi
lib = _mpatch.lib

@ffi.def_extern()
def cffi_get_next_item(arg, pos):
    all, bins = ffi.from_handle(arg)
    container = ffi.new("struct mpatch_flist*[1]")
    to_pass = ffi.new("char[]", str(bins[pos]))
    all.append(to_pass)
    r = lib.mpatch_decode(to_pass, len(to_pass) - 1, container)
    if r < 0:
        return ffi.NULL
    return container[0]

def patches(text, bins):
    lgt = len(bins)
    all = []
    if not lgt:
        return text
    arg = (all, bins)
    patch = lib.mpatch_fold(ffi.new_handle(arg),
                            lib.cffi_get_next_item, 0, lgt)
    if not patch:
        raise mpatchError("cannot decode chunk")
    outlen = lib.mpatch_calcsize(len(text), patch)
    if outlen < 0:
        lib.mpatch_lfree(patch)
        raise mpatchError("inconsistency detected")
    buf = ffi.new("char[]", outlen)
    if lib.mpatch_apply(buf, text, len(text), patch) < 0:
        lib.mpatch_lfree(patch)
        raise mpatchError("error applying patches")
    res = ffi.buffer(buf, outlen)[:]
    lib.mpatch_lfree(patch)
    return res