view mercurial/minifileset.py @ 45468:09edbff6ae8d

merge: store ACTION_KEEP_ABSENT when we are keeping the file absent locally

If a file is not present on the local side, and it's unchanged between other
merge parent and ancestor, we don't use any action, neither we had a if-else
branch for that condition. This leads to bid-merge missing that there is a
such action possible which can be performed.

As test changes demonstrate, we now choose the locally deleted side instead
of choosing the remote one consistently. This is also wrong behavior which is
resulted because of missing possible action. It will be fixed in next patch.

This whole logic is not acurrate as we should prompt user on what to do
when this kind of criss-cross merge is in play.

Differential Revision: https://phab.mercurial-scm.org/D8940

# minifileset.py - a simple language to select files
#
# Copyright 2017 Facebook, Inc.
#
# 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 .i18n import _
from . import (
    error,
    fileset,
    filesetlang,
    pycompat,
)


def _sizep(x):
    # i18n: "size" is a keyword
    expr = filesetlang.getstring(x, _(b"size requires an expression"))
    return fileset.sizematcher(expr)


def _compile(tree):
    if not tree:
        raise error.ParseError(_(b"missing argument"))
    op = tree[0]
    if op == b'withstatus':
        return _compile(tree[1])
    elif op in {b'symbol', b'string', b'kindpat'}:
        name = filesetlang.getpattern(
            tree, {b'path'}, _(b'invalid file pattern')
        )
        if name.startswith(b'**'):  # file extension test, ex. "**.tar.gz"
            ext = name[2:]
            for c in pycompat.bytestr(ext):
                if c in b'*{}[]?/\\':
                    raise error.ParseError(_(b'reserved character: %s') % c)
            return lambda n, s: n.endswith(ext)
        elif name.startswith(b'path:'):  # directory or full path test
            p = name[5:]  # prefix
            pl = len(p)
            f = lambda n, s: n.startswith(p) and (
                len(n) == pl or n[pl : pl + 1] == b'/'
            )
            return f
        raise error.ParseError(
            _(b"unsupported file pattern: %s") % name,
            hint=_(b'paths must be prefixed with "path:"'),
        )
    elif op in {b'or', b'patterns'}:
        funcs = [_compile(x) for x in tree[1:]]
        return lambda n, s: any(f(n, s) for f in funcs)
    elif op == b'and':
        func1 = _compile(tree[1])
        func2 = _compile(tree[2])
        return lambda n, s: func1(n, s) and func2(n, s)
    elif op == b'not':
        return lambda n, s: not _compile(tree[1])(n, s)
    elif op == b'func':
        symbols = {
            b'all': lambda n, s: True,
            b'none': lambda n, s: False,
            b'size': lambda n, s: _sizep(tree[2])(s),
        }

        name = filesetlang.getsymbol(tree[1])
        if name in symbols:
            return symbols[name]

        raise error.UnknownIdentifier(name, symbols.keys())
    elif op == b'minus':  # equivalent to 'x and not y'
        func1 = _compile(tree[1])
        func2 = _compile(tree[2])
        return lambda n, s: func1(n, s) and not func2(n, s)
    elif op == b'list':
        raise error.ParseError(
            _(b"can't use a list in this context"),
            hint=_(b'see \'hg help "filesets.x or y"\''),
        )
    raise error.ProgrammingError(b'illegal tree: %r' % (tree,))


def compile(text):
    """generate a function (path, size) -> bool from filter specification.

    "text" could contain the operators defined by the fileset language for
    common logic operations, and parenthesis for grouping.  The supported path
    tests are '**.extname' for file extension test, and '"path:dir/subdir"'
    for prefix test.  The ``size()`` predicate is borrowed from filesets to test
    file size.  The predicates ``all()`` and ``none()`` are also supported.

    '(**.php & size(">10MB")) | **.zip | (path:bin & !path:bin/README)' for
    example, will catch all php files whose size is greater than 10 MB, all
    files whose name ends with ".zip", and all files under "bin" in the repo
    root except for "bin/README".
    """
    tree = filesetlang.parse(text)
    tree = filesetlang.analyze(tree)
    tree = filesetlang.optimize(tree)
    return _compile(tree)