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Cached objects are virtual objects that can be set up without writing anything into the object store directly, which is used by git-blame(1) to create fake commits for the working tree. These cached objects are stored in a global variable, which is another roadblock for libification of the object subsystem. Refactor the code so that we instead store the array as part of the raw object store. This refactoring raises the question whether virtual objects should really be specific to a single repository (or rather a single object store). Hypothetical usecases might for example span across submodules, and here it may or may not be the right thing to provide virtual objects across submodule boundaries. The only existing usecase is git-blame(1) though, which does not know to blame across submodule boundaries in the first place. As such, storing these objects both globally and per-repository would achieve the same result right now. But arguably, if we learned to blame across submodule boundaries, we would likely want to create separate fare working tree commits for each of the submodules so that the user can learn which worktree a specific uncommitted change belongs to. And even if we would want to create the same fake commit for each of the submodules we could do that when storing separate virtual objects per object store. While this is all rather hypothetical, the takeaway is that handling virtual objects per-object store gives us more flexibility compared to storing them globally. In a hypothetical future where we have achieved full libification one might be able to handle unrelated repositories in a single process, where the state of one repository should not have an impact on the state of another repository. As such, storing these cached objects per object store will enable more usecases and should lead to less surprising outcomes overall. Signed-off-by: Patrick Steinhardt <ps@pks.im> 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