tests/autodiff.py

resourceutil: don't limit resources to the `mercurial` package

This should make things a little clearer, in that it now requires the full
package name to access a resource.  But the real motivation is that
`extensions._disabledpaths()` walks the `hgext` directory looking for bundled
extensions.  This in turn feeds, among other things:

    1) Listing disabled extensions in `hg help extensions`
    2) Indicating that an unknown command is in a non-enabled extension
    3) Displaying help for non-enabled extensions
    4) Generating documentation
    5) Announcing LFS is auto-enabled (or not) when cloning from an LFS source

The filesystem based ResourceReader will happily return *.py and *.pyc, but the
one supplied by PyOxidizer doesn't.  Presumably we can change that.  The only
other idea I had here is for setup.py to generate a text file containing the
list of extensions, but that doesn't seem great when running from source.

Differential Revision: https://phab.mercurial-scm.org/D7772

# Extension dedicated to test patch.diff() upgrade modes

from __future__ import absolute_import

from mercurial import (
    error,
    patch,
    pycompat,
    registrar,
    scmutil,
)

cmdtable = {}
command = registrar.command(cmdtable)


@command(
    b'autodiff',
    [(b'', b'git', b'', b'git upgrade mode (yes/no/auto/warn/abort)')],
    b'[OPTION]... [FILE]...',
)
def autodiff(ui, repo, *pats, **opts):
    opts = pycompat.byteskwargs(opts)
    diffopts = patch.difffeatureopts(ui, opts)
    git = opts.get(b'git', b'no')
    brokenfiles = set()
    losedatafn = None
    if git in (b'yes', b'no'):
        diffopts.git = git == b'yes'
        diffopts.upgrade = False
    elif git == b'auto':
        diffopts.git = False
        diffopts.upgrade = True
    elif git == b'warn':
        diffopts.git = False
        diffopts.upgrade = True

        def losedatafn(fn=None, **kwargs):
            brokenfiles.add(fn)
            return True

    elif git == b'abort':
        diffopts.git = False
        diffopts.upgrade = True

        def losedatafn(fn=None, **kwargs):
            raise error.Abort(b'losing data for %s' % fn)

    else:
        raise error.Abort(b'--git must be yes, no or auto')

    ctx1, ctx2 = scmutil.revpair(repo, [])
    m = scmutil.match(ctx2, pats, opts)
    it = patch.diff(
        repo,
        ctx1.node(),
        ctx2.node(),
        match=m,
        opts=diffopts,
        losedatafn=losedatafn,
    )
    for chunk in it:
        ui.write(chunk)
    for fn in sorted(brokenfiles):
        ui.write((b'data lost for: %s\n' % fn))