Bump actions/checkout from v5 to v6 and
git-for-windows/setup-git-for-windows-sdk from v1 to v2.
Both bumps are Node.js 20 to Node.js 24 runtime migrations with
no functional changes to the actions themselves. checkout v6 moves
persisted credentials to `` instead of `.git/config`,
which does not affect this workflow since no subsequent steps rely
on the credential location. The setup-sdk v2 provisions the same
minimal SDK as v1.
Risk: very low. The only precondition is a recent Actions Runner,
which github.com-hosted runners already satisfy.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Over time, as upstream Git absorbs fixes and features that originated in
or were carried by Git for Windows, downstream patches accumulate that
are no longer needed. The steady stream of merged PRs makes this
virtually inevitable. This PR collects fixup! commits to drop three such
patches during the next autosquash rebase.
The HTTP/2 workaround in `t5551` was a temporary fix for a libcurl
v8.10.0 regression on macOS CI runners. The faulty libcurl has long been
superseded by fixed versions, making it unnecessary.
The `unix-socket: avoid leak when initialization fails` patch changed
`return -1` to `goto fail` in `unix_stream_connect()` so cleanup would
run when `unix_sockaddr_init()` failed. Upstream fixed the same leak
more surgically in c5fe29f696 (unix-socket: fix memory leak when
chdir(3p) fails, 2025-01-30) by having `unix_sockaddr_init()` call
`FREE_AND_NULL(ctx->orig_dir)` before returning, making the downstream
caller-side fix redundant.
The `revision: create mark_trees_uninteresting_dense()` commit was a
preparatory patch for the path-walk API. That API has since been
upstreamed, and this commit became empty during the merging-rebase
because its changes were already in the new base.
AI-assisted contributions are a reality of open source in 2025 and
beyond. Contributors will use AI tools, and that includes the
maintainers themselves. Over recent months, I have found AI increasingly
useful for the kind of menial, tedious work that does not require much
creativity but is highly boring when done by hand: resolving merge
conflicts during merging-rebases, chasing down CI failures across
platforms, adapting downstream patches to upstream API changes.
To that end, I would like to have an `AGENTS.md` file in the code base
that helps any LLM to understand the context of the project.
A secondary goal of this is to preemptively help outside contributors.
The risk is not AI usage per se, but low-quality AI slop: contributions
where the human hits "accept" without sufficient context being available
to the model (and without proper review by the human, we've all been
there), resulting in changes that miss conventions, break patterns, or
misunderstand the project's architecture. Git's source code is about as
legacy as they come, having grown organically over two decades with no
design that AI coding models would readily grasp from a narrow code
sample alone.
This `AGENTS.md` is designed to raise the floor on AI-assisted
contributions by providing enough context that even when a human
contributor fails to steer carefully, the model has the information it
needs to produce something reasonable. It documents the repository
structure, build process, test conventions, the object model and ODB
internals, debugging techniques (Trace2, instrumenting tests, bisecting
failures), the merging-rebase workflow, conflict resolution patterns,
coding conventions (ASCII only, 80 columns, tabs), commit message
expectations, and the GitGitGadget contribution workflow. This is
information that a human might take for granted, but no coding model
will have been trained on specifically.
Similar `AGENTS.md` files have recently been added to other repositories
in the Git for Windows project:
[MINGW-packages](https://github.com/git-for-windows/MINGW-packages/pull/194),
[git-for-windows.github.io](https://github.com/git-for-windows/git-for-windows.github.io/pull/88)
and
[msys2-runtime](1e0ff37207).
This was a preparatory commit for the path-walk API, which has since
been upstreamed into v2.54.0. During the merging-rebase, the code
changes this commit introduced were already present in the new base,
leaving it empty. Drop it.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
AGENTS: document learnings from split-index + fsmonitor investigation
While investigating a CI failure in the `linux-TEST-vars` job caused by
the interaction between the `pt/fsmonitor-linux` and
`hn/git-checkout-m-with-stash` topics in `seen`, several debugging
techniques proved essential and were not previously documented.
The investigation required bisecting the first-parent history of `seen`
while temporarily merging the fsmonitor topic at each step. This
revealed that `GIT_TEST_SPLIT_INDEX=yes` corrupts the bisect
machinery's own index operations unless it is unset before cleanup
checkouts. It also revealed that `fprintf(stderr, ...)` instrumentation
in Git's C code is swallowed by the test framework, making Trace2 the
correct instrumentation approach.
A key insight was that the bug appeared Linux-specific only because
`linux-TEST-vars` is the sole CI job setting `GIT_TEST_SPLIT_INDEX=yes`;
there is no macOS or Windows equivalent. The actual root cause (the
`index.skipHash=true` + split-index interaction producing a null
`base_oid` in the shared index) is platform-independent.
Add four documentation sections capturing these learnings: bisecting
`seen` interactions, reproducing with exact CI variables, verifying CI
platform coverage before concluding platform-specificity, and using
Trace2 for instrumentation inside the test framework.
Assisted-by: Claude Opus 4.6
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This was marked as a temporary work-around in 4538ee661d (ci: work
around a problem with HTTP/2 vs libcurl v8.10.0 (#5165), 2024-09-24), to
help CI builds pass even on macOS. The faulty libcurl version has hence
been replaced with plenty of fixed ones, therefore this work-around is
no longer necessary.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
AGENTS.md: add pre-commit checklist for lint checks
Bundle the existing ASCII-only, 80-column, and whitespace validation
recipes into a "pre-commit checklist" block that agents should run
before every commit. The individual recipes already existed in the
Coding Conventions section but were presented as reference material
rather than as an actionable workflow step.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Claude Opus 4.6
Originally introduced as `core.useBuiltinFSMonitor` in Git for Windows
and developed, improved and stabilized there, the built-in FSMonitor
only made it into upstream Git (after unnecessarily long hemming and
hawing and throwing overly perfectionist style review sticks into the
spokes) as `core.fsmonitor = true`.
In Git for Windows, with this topic branch, we re-introduce the
now-obsolete config setting, with warnings suggesting to existing users
how to switch to the new config setting, with the intention to
ultimately drop the patch at some stage.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
AGENTS.md: document rebase, staging, and log -L tricks for AI agents
Add practical recipes for three workflows that are particularly useful
when AI agents work with Git:
Non-interactive "interactive" rebases using `sed -i 1ib` as a sequence
editor to insert a `break` command, then editing the todo file directly
via the path from `git rev-parse --git-path rebase-merge/git-rebase-todo`.
This avoids the impossible task of driving an interactive editor from an
AI agent.
Scripted hunk staging via `printf '%s\n' s y q | git add -p`, which
feeds predictable keystrokes to the add-patch protocol to stage
individual hunks without human interaction.
The `git log -L <start>,+<count>:<file>` trick for finding which commit
last touched specific lines, enabling an `hg absorb`-like workflow where
the agent can identify the right fixup! target surgically rather than
grepping through full diffs.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Claude Opus 4.6
This topic branch re-adds the deprecated --stdin/-z options to `git
reset`. Those patches were overridden by a different set of options in
the upstream Git project before we could propose `--stdin`.
We offered this in MinGit to applications that wanted a safer way to
pass lots of pathspecs to Git, and these applications will need to be
adjusted.
Instead of `--stdin`, `--pathspec-from-file=-` should be used, and
instead of `-z`, `--pathspec-file-nul`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
AGENTS.md: add upstream contribution and worktree guidance
Add sections covering the GitGitGadget workflow for contributing to
upstream Git, commit message conventions specific to the upstream
project, how to manage patch series with dependencies (branch
thickets), effective worktree usage including --update-refs for
history rewrites, and techniques for analyzing merge-structured
topic branches with git replay.
These learnings come from a session contributing the
safe.bareRepository test preparation patches via GitGitGadget.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Assisted-by: Claude Opus 4.6
A fix for calling `vim` in Windows Terminal caused a regression and was
reverted. We partially un-revert this, to get the fix again.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This adds an extensive section about resolving merge conflicts during
rebases, which happens quite often in Git for Windows' day-to-day.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In this time and age, AI is everywhere. However, it's sometimes not very
easy to use. For green-field projects it works quite a bit better than
for existing legacy projects. And Git's source code is _quite_ as legacy
code as they come... 😁
Now, the only way how AI can be used efficiently with legacy code
is by providing enough information by way of prompt context for the
AI to have a chance to make any sense of the code. The structure and
the architecture is, after all, not designed for AI, but rather the
opposite: By virtue of having grown organically over two decades, there
is no design that AI coding models would readily grasp.
So here is a document that describes all kinds of aspects about this
project. The idea is to help AI by providing information that it does
not have ingrained in its weights. The idea is to provide information
that a human prompter might take for granted, but no coding model will
have been trained on specifically.
Assisted-by: Claude Opus 4.5
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This is the recommended way on GitHub to describe policies revolving around
security issues and about supported versions.
Helped-by: Sven Strickroth <email@cs-ware.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reintroduce the 'core.useBuiltinFSMonitor' config setting (originally added
in 0a756b2a25 (fsmonitor: config settings are repository-specific,
2021-03-05)) after its removal from the upstream version of FSMonitor.
Upstream, the 'core.useBuiltinFSMonitor' setting was rendered obsolete by
"overloading" the 'core.fsmonitor' setting to take a boolean value. However,
several applications (e.g., 'scalar') utilize the original config setting,
so it should be preserved for a deprecation period before complete removal:
* if 'core.fsmonitor' is a boolean, the user is correctly using the new
config syntax; do not use 'core.useBuiltinFSMonitor'.
* if 'core.fsmonitor' is unspecified, use 'core.useBuiltinFSMonitor'.
* if 'core.fsmonitor' is a path, override and use the builtin FSMonitor if
'core.useBuiltinFSMonitor' is 'true'; otherwise, use the FSMonitor hook
indicated by the path.
Additionally, for this deprecation period, advise users to switch to using
'core.fsmonitor' to specify their use of the builtin FSMonitor.
Signed-off-by: Victoria Dye <vdye@github.com>
The `--stdin` option was a well-established paradigm in other commands,
therefore we implemented it in `git reset` for use by Visual Studio.
Unfortunately, upstream Git decided that it is time to introduce
`--pathspec-from-file` instead.
To keep backwards-compatibility for some grace period, we therefore
reinstate the `--stdin` option on top of the `--pathspec-from-file`
option, but mark it firmly as deprecated.
Helped-by: Victoria Dye <vdye@github.com>
Helped-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In e3f7e01b50 (Revert "editor: save and reset terminal after calling
EDITOR", 2021-11-22), we reverted the commit wholesale where the
terminal state would be saved and restored before/after calling an
editor.
The reverted commit was intended to fix a problem with Windows Terminal
where simply calling `vi` would cause problems afterwards.
To fix the problem addressed by the revert, but _still_ keep the problem
with Windows Terminal fixed, let's revert the revert, with a twist: we
restrict the save/restore _specifically_ to the case where `vi` (or
`vim`) is called, and do not do the same for any other editor.
This should still catch the majority of the cases, and will bridge the
time until the original patch is re-done in a way that addresses all
concerns.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git for Windows accepts pull requests; Core Git does not. Therefore we
need to adjust the template (because it only matches core Git's
project management style, not ours).
Also: direct Git for Windows enhancements to their contributions page,
space out the text for easy reading, and clarify that the mailing list
is plain text, not HTML.
Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Rather than using private IFTTT Applets that send mails to this
maintainer whenever a new version of a Git for Windows component was
released, let's use the power of GitHub workflows to make this process
publicly visible.
This workflow monitors the Atom/RSS feeds, and opens a ticket whenever a
new version was released.
Note: Bash sometimes releases multiple patched versions within a few
minutes of each other (i.e. 5.1p1 through 5.1p4, 5.0p15 and 5.0p16). The
MSYS2 runtime also has a similar system. We can address those patches as
a group, so we shouldn't get multiple issues about them.
Note further: We're not acting on newlib releases, OpenSSL alphas, Perl
release candidates or non-stable Perl releases. There's no need to open
issues about them.
Co-authored-by: Matthias Aßhauer <mha1993@live.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This patch introduces support to set special NTFS attributes that are
interpreted by the Windows Subsystem for Linux as file mode bits, UID
and GID.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Previously, we did not install any handler for Ctrl+C, but now we really
want to because the MSYS2 runtime learned the trick to call the
ConsoleCtrlHandler when Ctrl+C was pressed.
With this, hitting Ctrl+C while `git log` is running will only terminate
the Git process, but not the pager. This finally matches the behavior on
Linux and on macOS.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Windows Subsystem for Linux (WSL) version 2 allows to use `chmod` on
NTFS volumes provided that they are mounted with metadata enabled (see
https://devblogs.microsoft.com/commandline/chmod-chown-wsl-improvements/
for details), for example:
$ chmod 0755 /mnt/d/test/a.sh
In order to facilitate better collaboration between the Windows
version of Git and the WSL version of Git, we can make the Windows
version of Git also support reading and writing NTFS file modes
in a manner compatible with WSL.
Since this slightly slows down operations where lots of files are
created (such as an initial checkout), this feature is only enabled when
`core.WSLCompat` is set to true. Note that you also have to set
`core.fileMode=true` in repositories that have been initialized without
enabling WSL compatibility.
There are several ways to enable metadata loading for NTFS volumes
in WSL, one of which is to modify `/etc/wsl.conf` by adding:
```
[automount]
enabled = true
options = "metadata,umask=027,fmask=117"
```
And reboot WSL.
It can also be enabled temporarily by this incantation:
$ sudo umount /mnt/c &&
sudo mount -t drvfs C: /mnt/c -o metadata,uid=1000,gid=1000,umask=22,fmask=111
It's important to note that this modification is compatible with, but
does not depend on WSL. The helper functions in this commit can operate
independently and functions normally on devices where WSL is not
installed or properly configured.
Signed-off-by: xungeng li <xungeng@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The TerminateProcess() function does not actually leave the child
processes any chance to perform any cleanup operations. This is bad
insofar as Git itself expects its signal handlers to run.
A symptom is e.g. a left-behind .lock file that would not be left behind
if the same operation was run, say, on Linux.
To remedy this situation, we use an obscure trick: we inject a thread
into the process that needs to be killed and to let that thread run the
ExitProcess() function with the desired exit status. Thanks J Wyman for
describing this trick.
The advantage is that the ExitProcess() function lets the atexit
handlers run. While this is still different from what Git expects (i.e.
running a signal handler), in practice Git sets up signal handlers and
atexit handlers that call the same code to clean up after itself.
In case that the gentle method to terminate the process failed, we still
fall back to calling TerminateProcess(), but in that case we now also
make sure that processes spawned by the spawned process are terminated;
TerminateProcess() does not give the spawned process a chance to do so
itself.
Please note that this change only affects how Git for Windows tries to
terminate processes spawned by Git's own executables. Third-party
software that *calls* Git and wants to terminate it *still* need to make
sure to imitate this gentle method, otherwise this patch will not have
any effect.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Getting started contributing to Git can be difficult on a Windows
machine. CONTRIBUTING.md contains a guide to getting started, including
detailed steps for setting up build tools, running tests, and
submitting patches to upstream.
[includes an example by Pratik Karki how to submit v2, v3, v4, etc.]
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
With this patch, Git for Windows works as intended on mounted APFS
volumes (where renaming read-only files would fail).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Git project followed Git for Windows' lead and added their Code of
Conduct, based on the Contributor Covenant v1.4, later updated to v2.0.
We adapt it slightly to Git for Windows.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The Git for Windows project has grown quite complex over the years,
certainly much more complex than during the first years where the
`msysgit.git` repository was abusing Git for package management purposes
and the `git/git` fork was called `4msysgit.git`.
Let's describe the status quo in a thorough way.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
These are Git for Windows' Git GUI and gitk patches. We will have to
decide at some point what to do about them, but that's a little lower
priority (as Git GUI seems to be unmaintained for the time being, and
the gitk maintainer keeps a very low profile on the Git mailing list,
too).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, the current working directory is pretty much guaranteed to
contain a colon. If we feed that path to CVS, it mistakes it for a
separator between host and port, though.
This has not been a problem so far because Git for Windows uses MSYS2's
Bash using a POSIX emulation layer that also pretends that the current
directory is a Unix path (at least as long as we're in a shell script).
However, that is rather limiting, as Git for Windows also explores other
ports of other Unix shells. One of those is BusyBox-w32's ash, which is
a native port (i.e. *not* using any POSIX emulation layer, and certainly
not emulating Unix paths).
So let's just detect if there is a colon in $PWD and punt in that case.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
To verify that the symlink is resolved correctly, we use the fact that
`git.exe` is a native Win32 program, and that `git.exe config -f <path>`
therefore uses the native symlink resolution.
Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git for Windows uses MSYS2's Bash to run the test suite, which comes
with benefits but also at a heavy price: on the plus side, MSYS2's
POSIX emulation layer allows us to continue pretending that we are on a
Unix system, e.g. use Unix paths instead of Windows ones, yet this is
bought at a rather noticeable performance penalty.
There *are* some more native ports of Unix shells out there, though,
most notably BusyBox-w32's ash. These native ports do not use any POSIX
emulation layer (or at most a *very* thin one, choosing to avoid
features such as fork() that are expensive to emulate on Windows), and
they use native Windows paths (usually with forward slashes instead of
backslashes, which is perfectly legal in almost all use cases).
And here comes the problem: with a $PWD looking like, say,
C:/git-sdk-64/usr/src/git/t/trash directory.t5813-proto-disable-ssh
Git's test scripts get quite a bit confused, as their assumptions have
been shattered. Not only does this path contain a colon (oh no!), it
also does not start with a slash.
This is a problem e.g. when constructing a URL as t5813 does it:
ssh://remote$PWD. Not only is it impossible to separate the "host" from
the path with a $PWD as above, even prefixing $PWD by a slash won't
work, as /C:/git-sdk-64/... is not a valid path.
As a workaround, detect when $PWD does not start with a slash on
Windows, and simply strip the drive prefix, using an obscure feature of
Windows paths: if an absolute Windows path starts with a slash, it is
implicitly prefixed by the drive prefix of the current directory. As we
are talking about the current directory here, anyway, that strategy
works.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, symbolic links have a type: a "file symlink" must point at
a file, and a "directory symlink" must point at a directory. If the
type of symlink does not match its target, it doesn't work.
Git does not record the type of symlink in the index or in a tree. On
checkout it'll guess the type, which only works if the target exists
at the time the symlink is created. This may often not be the case,
for example when the link points at a directory inside a submodule.
By specifying `symlink=file` or `symlink=dir` the user can specify what
type of symlink Git should create, so Git doesn't have to rely on
unreliable heuristics.
Signed-off-by: Bert Belder <bertbelder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When t5605 tries to verify that files are hardlinked (or that they are
not), it uses the `-links` option of the `find` utility.
BusyBox' implementation does not support that option, and BusyBox-w32's
lstat() does not even report the number of hard links correctly (for
performance reasons).
So let's just switch to a different method that actually works on
Windows.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
While it may seem super convenient to some old Unix hands to simpy
require Perl to be available when running the test suite, this is a
major hassle on Windows, where we want to verify that Perl is not,
actually, required in a NO_PERL build.
As a super ugly workaround, we "install" a script into /usr/bin/perl
reading like this:
#!/bin/sh
# We'd much rather avoid requiring Perl altogether when testing
# an installed Git. Oh well, that's why we cannot have nice
# things.
exec c:/git-sdk-64/usr/bin/perl.exe "$@"
The problem with that is that BusyBox assumes that the #! line in a
script refers to an executable, not to a script. So when it encounters
the line #!/usr/bin/perl in t5532's proxy-get-cmd, it barfs.
Let's help this situation by simply executing the Perl script with the
"interpreter" specified explicitly.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
At some stage, t5003-archive-zip wants to add a file that is not ASCII.
To that end, it uses /bin/sh. But that file may actually not exist (it
is too easy to forget that not all the world is Unix/Linux...)! Besides,
we already have perfectly fine binary files intended for use solely by
the tests. So let's use one of them instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When running with BusyBox, we will want to avoid calling executables on
the PATH that are implemented in BusyBox itself.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
