The git-diff command can directly compare two blobs (or a
blob and a file), but we don't test this at all. Let's add
some basic tests that reveal a few problems.
There are basically four interesting inputs:
1. sha1 against sha1 (where diff has no information beyond
the contents)
2. tree:path against tree:path (where it can get
information via get_sha1_with_context)
3. Same as (2), but using the ".." range syntax
4. tree:path against a filename
And beyond generating a sane diff, we care about a few
little bits: which paths they show in the diff header, and
whether they correctly pick up a mode change.
They should all be able to show a mode except for (1),
though note that case (3) is currently broken.
For the headers, we would ideally show the path within the
tree if we have it, making:
git diff a:path b:path
look the same as:
git diff a b -- path
We can't always do that (e.g., in the direct sha1/sha1 diff,
we have no path to show), in which case we should fall back
to the name that resolved to the blob (which is nonsense
from the repository's perspective, but is the best we can
do).
Aside from the fallback case in (1), none of the cases get
this right. Cases (2) and (3) always show the full
tree:path, even though we should be able to know just the
"path" portion.
Case (4) picks up the filename path, but assigns it to
_both_ sides of the diff. So this works for:
git diff tree:path path
but not for:
git diff tree:other_path path
The appropriate tests are marked to expect failure.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just "subscribe git" in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://public-inbox.org/git/, http://marc.info/?l=git and other archival sites.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks