Fix "git diff --stat" for interesting - but empty - file changes

The behavior of "git diff --stat" is rather odd for files that have
zero lines of changes: it will discount them entirely unless they were
renames.

Which means that the stat output will simply not show files that only
had "other" changes: they were created or deleted, or their mode was
changed.

Now, those changes do show up in the summary, but so do renames, so
the diffstat logic is inconsistent. Why does it show renames with zero
lines changed, but not mode changes or added files with zero lines
changed?

So change the logic to not check for "is_renamed", but for
"is_interesting" instead, where "interesting" is judged to be any
action but a pure data change (because a pure data change with zero
data changed really isn't worth showing, if we ever get one in our
diffpairs).

So if you did

   chmod +x Makefile
   git diff --stat

before, it would show empty (" 0 files changed"), with this it shows

 Makefile | 0
 1 file changed, 0 insertions(+), 0 deletions(-)

which I think is a more correct diffstat (and then with "--summary" it
shows *what* the metadata change to Makefile was - this is completely
consistent with our handling of renamed files).

Side note: the old behavior was *really* odd. With no changes at all,
"git diff --stat" output was empty. With just a chmod, it said "0
files changed". No way is our legacy behavior sane.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
t1400-update-ref: Add test verifying bug with symrefs in delete_ref()

When deleting a ref through a symref (e.g. using 'git update-ref -d HEAD'
to delete refs/heads/master), we currently fail to remove the packed
version of that ref. This testcase demonstrates the bug.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix failure to delete a packed ref through a symref

When deleting a ref through a symref (e.g. using 'git update-ref -d HEAD'
to delete refs/heads/master), we would remove the loose ref, but a packed
version of the same ref would remain, the end result being that instead of
deleting refs/heads/master we would appear to reset it to its state as of
the last repack.

This patch fixes the issue, by making sure we pass the correct ref name
when invoking repack_without_ref() from within delete_ref().

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pickaxe: hoist empty needle check

If we are given an empty pickaxe needle like "git log -S ''",
it is impossible for us to find anything (because no matter
what the content, the count will always be 0). We currently
check this at the lowest level of contains(). Let's hoist
the logic much earlier to has_changes(), so that it is
simpler to return our answer before loading any blob data.

Signed-off-by: Jeff King <peff@peff.net>
pickaxe: use textconv for -S counting

We currently just look at raw blob data when using "-S" to
pickaxe. This is mostly historical, as pickaxe predates the
textconv feature. If the user has bothered to define a
textconv filter, it is more likely that their search string will be
on the textconv output, as that is what they will see in the
diff (and we do not even provide a mechanism for them to
search for binary needles that contain NUL characters).

This patch teaches "-S" to use textconv, just as we
already do for "-G".

Signed-off-by: Jeff King <peff@peff.net>
Add new remote-hg transport helper

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add support for pushing

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add support for remote pushing

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add support to push URLs

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: make sure the encoding is correct

Independently of the environment.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: match hg merge behavior

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add support for hg-git compat mode

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add compat for hg-git author fixes

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: fake bookmark when there's none

Or at least no current bookmark.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add basic tests

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
test-lib: avoid full path to store test results

No reason to use the full path in case this is used externally.

Otherwise we might get errors such as:

./test-lib.sh: line 394: /home/bob/dev/git/t/test-results//home/bob/dev/git/contrib/remote-hg/test-2894.counts: No such file or directory

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add bidirectional tests

Base commands from hg-git tests:
https://bitbucket.org/durin42/hg-git/src

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add tests to compare with hg-git

The base commands come from the tests of the hg-git project.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add extra author test

For hg.hg.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
remote-hg: add option to not track branches

Some people prefer it this way.

 % git config --global remote-hg.track-branches false

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>