When a user runs 'git log', they expect a certain set of helpful
decorations. This includes:
* The HEAD ref
* Branches (refs/heads/)
* Stashes (refs/stash)
* Tags (refs/tags/)
* Remote branches (refs/remotes/)
* Replace refs (refs/replace/ or $GIT_REPLACE_REF_BASE)
Each of these namespaces was selected due to existing test cases that
verify these namespaces appear in the decorations. In particular,
stashes and replace refs can have custom colors from the
color.decorate.<slot> config option.
While one test checks for a decoration from notes, it only applies to
the tip of refs/notes/commit (or its configured ref name). Notes form
their own kind of decoration instead. Modify the expected output for the
tests in t4013 that expect this note decoration. There are several
tests throughout the codebase that verify that --decorate-refs,
--decorate-refs-exclude, and log.excludeDecoration work as designed and
the tests continue to pass without intervention.
However, there are other refs that are less helpful to show as
decoration:
* Prefetch refs (refs/prefetch/)
* Rebase refs (refs/rebase-merge/ and refs/rebase-apply/)
* Bundle refs (refs/bundle/) [!]
[!] The bundle refs are part of a parallel series that bootstraps a repo
from a bundle file, storing the bundle's refs into the repo's
refs/bundle/ namespace.
In the case of prefetch refs, 96eaffebbf3d0 (maintenance: set
log.excludeDecoration durin prefetch, 2021-01-19) added logic to add
refs/prefetch/ to the log.excludeDecoration config option. Additional
feedback pointed out that having such a side-effect can be confusing and
perhaps not helpful to users. Instead, we should hide these ref
namespaces that are being used by Git for internal reasons but are not
helpful for the users to see.
The way to provide a seamless user experience without setting the config
is to modify the default decoration filters to match our expectation of
what refs the user actually wants to see.
In builtin/log.c, after parsing the --decorate-refs and
--decorate-refs-exclude options from the command-line, call
set_default_decoration_filter(). This method populates the exclusions
from log.excludeDecoration, then checks if the list of pattern
modifications are empty. If none are specified, then the default set is
restricted to the set of inclusions mentioned earlier (HEAD, branches,
etc.). A previous change introduced the ref_namespaces array, which
includes all of these currently-used namespaces. The 'decoration' value
is non-zero when that namespace is associated with a special coloring
and fits into the list of "expected" decorations as described above,
which makes the implementation of this filter very simple.
Note that the logic in ref_filter_match() in log-tree.c follows this
matching pattern:
1. If there are exclusion patterns and the ref matches one, then ignore
the decoration.
2. If there are inclusion patterns and the ref matches one, then
definitely include the decoration.
3. If there are config-based exclusions from log.excludeDecoration and
the ref matches one, then ignore the decoration.
With this logic in mind, we need to ensure that we do not populate our
new defaults if any of these filters are manually set. Specifically, if
a user runs
git -c log.excludeDecoration=HEAD log
then we expect the HEAD decoration to not appear. If we left the default
inclusions in the set, then HEAD would match that inclusion before
reaching the config-based exclusions.
A potential alternative would be to check the list of default inclusions
at the end, after the config-based exclusions. This would still create a
behavior change for some uses of --decorate-refs-exclude=<X>, and could
be overwritten somewhat with --decorate-refs=refs/ and
--decorate-refs=HEAD. However, it no longer becomes possible to include
refs outside of the defaults while also excluding some using
log.excludeDecoration.
Another alternative would be to exclude the known namespaces that are
not intended to be shown. This would reduce the visible effect of the
change for expert users who use their own custom ref namespaces. The
implementation change would be very simple to swap due to our use of
ref_namespaces:
int i;
struct string_list *exclude = decoration_filter->exclude_ref_pattern;
/*
* No command-line or config options were given, so
* populate with sensible defaults.
*/
for (i = 0; i < NAMESPACE__COUNT; i++) {
if (ref_namespaces[i].decoration)
continue;
string_list_append(exclude, ref_namespaces[i].ref);
}
The main downside of this approach is that we expect to add new hidden
namespaces in the future, and that means that Git versions will be less
stable in how they behave as those namespaces are added.
It is critical that we provide ways for expert users to disable this
behavior change via command-line options and config keys. These changes
will be implemented in a future change.
Add a test that checks that the defaults are not added when
--decorate-refs is specified. We verify this by showing that HEAD is not
included as it normally would. Also add a test that shows that the
default filter avoids the unwanted decorations from refs/prefetch,
refs/rebase-merge,
and refs/bundle.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
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-<commandname>.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 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 with just "subscribe git" in the body to majordomo@vger.kernel.org (not the Git list). The mailing list archives are available at https://lore.kernel.org/git/, http://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