mirror of
https://github.com/git/git.git
synced 2026-01-12 05:43:12 +09:00
c702dd4856
In git-fetch we have an optimization to avoid issuing an ls-refs command to the server if we don't care about the value of any refs (e.g., because we are fetching exact object ids), saving a round-trip to the server. This comes from e70a3030e7 (fetch: do not list refs if fetching only hashes, 2018-09-27). It uses an explicit flag "must_list_refs" to decide when we need to do so. That was needed back then, because the list of ref-prefixes was not always complete. If it was empty, it did not necessarily mean that we were not interested in any refs). But that is no longer the case; an empty list of prefixes means that we truly do not care about any refs. And so rather than an explicit flag, we can just check whether we are interested in any ref prefixes. This simplifies the code slightly, as there is now a single source of truth for the decision. It also fixes a bug in / optimizes a very unlikely case, which is: git fetch $remote ^foo $oid I.e., a negative refspec combined with an exact oid fetch. This is somewhat nonsense, in that there are no positive refspecs mentioning refs to countermand with the negative one. But we should be able to do this without issuing an ls-refs command (excluding "foo" from the empty set will obviously still be the empty set). However, the current code does not do so. The negative refspec is not counted as a noop in un-setting the must_list_refs flag (hardly the fault of e70a3030e7, as negative refspecs did not appear until much later). But by using the prefix list as a source of truth, this naturally just works; the negative refspec does not add a prefix to ask about, and hence does not trigger the ls-refs call. This is esoteric enough that I didn't bother adding a test. The real value here is in the code simplification. 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.adoc to get started, then see
Documentation/giteveryday.adoc for a useful minimum set of commands, and
Documentation/git-<commandname>.adoc 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.adoc
(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 and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
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