view tests/autodiff.py @ 41454:d1d3094b54f9

patch: handle 0 context lines (diff.unified=0) when parsing patches

Previously, if there were no context lines, we would just keep updating the
ranges and the hunk, but not actually storing the hunk (just overwriting it each
time).  Thus a diff like this:

    $ hg diff --config diff.unified=0
    diff --git a/bar b/bar
    --- a/bar
    +++ b/bar
    @@ -1,0 +2,1 @@ 1
    +change1
    @@ -3,0 +5,1 @@ 3
    +change2

would come out of the parser like this (change1 is lost):

    bar:
    @@ -3,0 +5,1 @@ 3
    +change2

This had some really weird side effects for things like commit --interactive,
split, etc.

Differential Revision: https://phab.mercurial-scm.org/D5743

# 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))