view contrib/hgfixes/fix_bytesmod.py @ 21932:21a2f31f054d stable

largefiles: use "normallookup", if "mtime" of standin is unset

Before this patch, largefiles gotten from "other" revision (without
conflict) at "hg merge" become "clean" unexpectedly in steps below:

    1. "merge.update()" is invoked
      1-1 standinfile SF is updated in the working directory
      1-2 "dirstate" entry for SF is "normallookup"-ed

    2. "lfcommands.updatelfiles()" is invoked (by "overrides.hgmerge()")
      2-1 largefile LF (for SF) is updated in the working directory
      2-2 "dirstate" returns "n" for SF (by 1-2)
      2-3 "lfdirstate" entry for LF is "normal"-ed
      2-4 "lfdirstate" is written into ".hg/largefiles/dirstate", and
          timestamp of LF is stored into "lfdirstate" file
          (ASSUMPTION: timestamp of LF differs from one of "lfdirstate" file)

Then, "hs status" treats LF as "clean", even though LF is updated by
"other" revision (by 2-1), because "lfilesrepo.status()" always treats
"normal"-ed files (by 2-3 and 2-4) as "clean".

When timestamp is not set (= negative value) for standinfile in
"dirstate", largefile should be "normallookup"-ed regardless of
rebasing or not, because "n" state in "dirstate" doesn't ensure
"clean"-ness of a standinfile at that time.

This patch uses "normallookup" instead of "normal", if "mtime" of
standin is unset

This is a temporary way to fix with less changes. For fundamental
resolution of this kind of problems in the future, "lfdirstate" should
be updated with "dirstate" simultaneously while "merge.update"
execution: maybe by hooking "recordupdates"

It is also why this patch (temporarily) uses internal field "_map" of
"dirstate" directly.

This patch uses "[debug] dirstate.delaywrite" feature in the test, to
ensure that timestamp of the largefile gotten from "other" revision is
stored into ".hg/largefiles/dirstate". (for ASSUMPTION at 2-4)

This patch newly adds "test-largefiles-update.t", to avoid increasing
cost to run other tests for largefiles by subsequent patches
(especially, "[debug] dirstate.delaywrite" causes so).

"""Fixer that changes bytes % whatever to a function that actually formats
it."""

from lib2to3 import fixer_base
from lib2to3.fixer_util import is_tuple, Call, Comma, Name, touch_import

# XXX: Implementing a blacklist in 2to3 turned out to be more troublesome than
# blacklisting some modules inside the fixers. So, this is what I came with.

blacklist = ['mercurial/demandimport.py',
             'mercurial/py3kcompat.py',
             'mercurial/i18n.py',
            ]

def isnumberremainder(formatstr, data):
    try:
        if data.value.isdigit():
            return True
    except AttributeError:
        return False

class FixBytesmod(fixer_base.BaseFix):
    # XXX: There's one case (I suppose) I can't handle: when a remainder
    # operation like foo % bar is performed, I can't really know what the
    # contents of foo and bar are. I believe the best approach is to "correct"
    # the to-be-converted code and let bytesformatter handle that case in
    # runtime.
    PATTERN = '''
              term< formatstr=STRING '%' data=STRING > |
              term< formatstr=STRING '%' data=atom > |
              term< formatstr=NAME '%' data=any > |
              term< formatstr=any '%' data=any >
              '''

    def transform(self, node, results):
        for bfn in blacklist:
            if self.filename.endswith(bfn):
                return
        if not self.filename.endswith('mercurial/py3kcompat.py'):
            touch_import('mercurial', 'py3kcompat', node=node)

        formatstr = results['formatstr'].clone()
        data = results['data'].clone()
        formatstr.prefix = '' # remove spaces from start

        if isnumberremainder(formatstr, data):
            return

        # We have two possibilities:
        # 1- An identifier or name is passed, it is going to be a leaf, thus, we
        #    just need to copy its value as an argument to the formatter;
        # 2- A tuple is explicitly passed. In this case, we're gonna explode it
        # to pass to the formatter
        # TODO: Check for normal strings. They don't need to be translated

        if is_tuple(data):
            args = [formatstr, Comma().clone()] + \
                   [c.clone() for c in data.children[:]]
        else:
            args = [formatstr, Comma().clone(), data]

        call = Call(Name('bytesformatter', prefix=' '), args)
        return call