GIT-PULL(1) Git Manual GIT-PULL(1)

NAME

git-pull - Fetch from and integrate with another repository or a
local branch

SYNOPSIS

git pull [<options>] [<repository> [<refspec>...]]

DESCRIPTION

Incorporates changes from a remote repository into the current
branch. If the current branch is behind the remote, then by default
it will fast-forward the current branch to match the remote. If the
current branch and the remote have diverged, the user needs to
specify how to reconcile the divergent branches with --rebase or
--no-rebase (or the corresponding configuration option in
pull.rebase).

More precisely, git pull runs git fetch with the given parameters and
then depending on configuration options or command line flags, will
call either git rebase or git merge to reconcile diverging branches.

<repository> should be the name of a remote repository as passed to
git-fetch(1). <refspec> can name an arbitrary remote ref (for
example, the name of a tag) or even a collection of refs with
corresponding remote-tracking branches (e.g.,
refs/heads/*:refs/remotes/origin/*), but usually it is the name of a
branch in the remote repository.

Default values for <repository> and <branch> are read from the
"remote" and "merge" configuration for the current branch as set by
git-branch(1) --track.

Assume the following history exists and the current branch is
"master":

A---B---C master on origin
/
D---E---F---G master
^
origin/master in your repository

Then "git pull" will fetch and replay the changes from the remote
master branch since it diverged from the local master (i.e., E) until
its current commit (C) on top of master and record the result in a
new commit along with the names of the two parent commits and a log
message from the user describing the changes.

A---B---C origin/master
/ \
D---E---F---G---H master

See git-merge(1) for details, including how conflicts are presented
and handled.

In Git 1.7.0 or later, to cancel a conflicting merge, use git reset
--merge. Warning: In older versions of Git, running git pull with
uncommitted changes is discouraged: while possible, it leaves you in
a state that may be hard to back out of in the case of a conflict.

If any of the remote changes overlap with local uncommitted changes,
the merge will be automatically canceled and the work tree untouched.
It is generally best to get any local changes in working order before
pulling or stash them away with git-stash(1).

OPTIONS

-q, --quiet
This is passed to both underlying git-fetch to squelch reporting
of during transfer, and underlying git-merge to squelch output
during merging.

-v, --verbose
Pass --verbose to git-fetch and git-merge.

--[no-]recurse-submodules[=(yes|on-demand|no)]
This option controls if new commits of populated submodules
should be fetched, and if the working trees of active submodules
should be updated, too (see git-fetch(1), git-config(1) and
gitmodules(5)).

If the checkout is done via rebase, local submodule commits are
rebased as well.

If the update is done via merge, the submodule conflicts are
resolved and checked out.

Options related to merging

--commit, --no-commit
Perform the merge and commit the result. This option can be used
to override --no-commit. Only useful when merging.

With --no-commit perform the merge and stop just before creating
a merge commit, to give the user a chance to inspect and further
tweak the merge result before committing.

Note that fast-forward updates do not create a merge commit and
therefore there is no way to stop those merges with --no-commit.
Thus, if you want to ensure your branch is not changed or updated
by the merge command, use --no-ff with --no-commit.

--edit, -e, --no-edit
Invoke an editor before committing successful mechanical merge to
further edit the auto-generated merge message, so that the user
can explain and justify the merge. The --no-edit option can be
used to accept the auto-generated message (this is generally
discouraged).

Older scripts may depend on the historical behaviour of not
allowing the user to edit the merge log message. They will see an
editor opened when they run git merge. To make it easier to
adjust such scripts to the updated behaviour, the environment
variable GIT_MERGE_AUTOEDIT can be set to no at the beginning of
them.

--cleanup=<mode>
This option determines how the merge message will be cleaned up
before committing. See git-commit(1) for more details. In
addition, if the <mode> is given a value of scissors, scissors
will be appended to MERGE_MSG before being passed on to the
commit machinery in the case of a merge conflict.

--ff-only
Only update to the new history if there is no divergent local
history. This is the default when no method for reconciling
divergent histories is provided (via the --rebase=* flags).

--ff, --no-ff
When merging rather than rebasing, specifies how a merge is
handled when the merged-in history is already a descendant of the
current history. If merging is requested, --ff is the default
unless merging an annotated (and possibly signed) tag that is not
stored in its natural place in the refs/tags/ hierarchy, in which
case --no-ff is assumed.

With --ff, when possible resolve the merge as a fast-forward
(only update the branch pointer to match the merged branch; do
not create a merge commit). When not possible (when the merged-in
history is not a descendant of the current history), create a
merge commit.

With --no-ff, create a merge commit in all cases, even when the
merge could instead be resolved as a fast-forward.

-S[<keyid>], --gpg-sign[=<keyid>], --no-gpg-sign
GPG-sign the resulting merge commit. The keyid argument is
optional and defaults to the committer identity; if specified, it
must be stuck to the option without a space. --no-gpg-sign is
useful to countermand both commit.gpgSign configuration variable,
and earlier --gpg-sign.

--log[=<n>], --no-log
In addition to branch names, populate the log message with
one-line descriptions from at most <n> actual commits that are
being merged. See also git-fmt-merge-msg(1). Only useful when
merging.

With --no-log do not list one-line descriptions from the actual
commits being merged.

--signoff, --no-signoff
Add a Signed-off-by trailer by the committer at the end of the
commit log message. The meaning of a signoff depends on the
project to which you're committing. For example, it may certify
that the committer has the rights to submit the work under the
project's license or agrees to some contributor representation,
such as a Developer Certificate of Origin. (See
https://developercertificate.org for the one used by the Linux
kernel and Git projects.) Consult the documentation or leadership
of the project to which you're contributing to understand how the
signoffs are used in that project.

The --no-signoff option can be used to countermand an earlier
--signoff option on the command line.

--stat, -n, --no-stat
Show a diffstat at the end of the merge. The diffstat is also
controlled by the configuration option merge.stat.

With -n or --no-stat do not show a diffstat at the end of the
merge.

--squash, --no-squash
Produce the working tree and index state as if a real merge
happened (except for the merge information), but do not actually
make a commit, move the HEAD, or record $GIT_DIR/MERGE_HEAD (to
cause the next git commit command to create a merge commit). This
allows you to create a single commit on top of the current branch
whose effect is the same as merging another branch (or more in
case of an octopus).

With --no-squash perform the merge and commit the result. This
option can be used to override --squash.

With --squash, --commit is not allowed, and will fail.

Only useful when merging.

--[no-]verify
By default, the pre-merge and commit-msg hooks are run. When
--no-verify is given, these are bypassed. See also githooks(5).
Only useful when merging.

-s <strategy>, --strategy=<strategy>
Use the given merge strategy; can be supplied more than once to
specify them in the order they should be tried. If there is no -s
option, a built-in list of strategies is used instead (ort when
merging a single head, octopus otherwise).

-X <option>, --strategy-option=<option>
Pass merge strategy specific option through to the merge
strategy.

--verify-signatures, --no-verify-signatures
Verify that the tip commit of the side branch being merged is
signed with a valid key, i.e. a key that has a valid uid: in the
default trust model, this means the signing key has been signed
by a trusted key. If the tip commit of the side branch is not
signed with a valid key, the merge is aborted.

Only useful when merging.

--summary, --no-summary
Synonyms to --stat and --no-stat; these are deprecated and will
be removed in the future.

--autostash, --no-autostash
Automatically create a temporary stash entry before the operation
begins, record it in the ref MERGE_AUTOSTASH and apply it after
the operation ends. This means that you can run the operation on
a dirty worktree. However, use with care: the final stash
application after a successful merge might result in non-trivial
conflicts.

--allow-unrelated-histories
By default, git merge command refuses to merge histories that do
not share a common ancestor. This option can be used to override
this safety when merging histories of two projects that started
their lives independently. As that is a very rare occasion, no
configuration variable to enable this by default exists and will
not be added.

Only useful when merging.

-r, --rebase[=(false|true|merges|interactive)]
When true, rebase the current branch on top of the upstream
branch after fetching. If there is a remote-tracking branch
corresponding to the upstream branch and the upstream branch was
rebased since last fetched, the rebase uses that information to
avoid rebasing non-local changes.

When set to merges, rebase using git rebase --rebase-merges so
that the local merge commits are included in the rebase (see git-
rebase(1) for details).

When false, merge the upstream branch into the current branch.

When interactive, enable the interactive mode of rebase.

See pull.rebase, branch.<name>.rebase and branch.autoSetupRebase
in git-config(1) if you want to make git pull always use --rebase
instead of merging.

Note
This is a potentially dangerous mode of operation. It
rewrites history, which does not bode well when you published
that history already. Do not use this option unless you have
read git-rebase(1) carefully.

--no-rebase
This is shorthand for --rebase=false.

Options related to fetching

--[no-]all
Fetch all remotes, except for the ones that has the
remote.<name>.skipFetchAll configuration variable set. This
overrides the configuration variable fetch.all`.

-a, --append
Append ref names and object names of fetched refs to the existing
contents of .git/FETCH_HEAD. Without this option old data in
.git/FETCH_HEAD will be overwritten.

--atomic
Use an atomic transaction to update local refs. Either all refs
are updated, or on error, no refs are updated.

--depth=<depth>
Limit fetching to the specified number of commits from the tip of
each remote branch history. If fetching to a shallow repository
created by git clone with --depth=<depth> option (see git-
clone(1)), deepen or shorten the history to the specified number
of commits. Tags for the deepened commits are not fetched.

--deepen=<depth>
Similar to --depth, except it specifies the number of commits
from the current shallow boundary instead of from the tip of each
remote branch history.

--shallow-since=<date>
Deepen or shorten the history of a shallow repository to include
all reachable commits after <date>.

--shallow-exclude=<ref>
Deepen or shorten the history of a shallow repository to exclude
commits reachable from a specified remote branch or tag. This
option can be specified multiple times.

--unshallow
If the source repository is complete, convert a shallow
repository to a complete one, removing all the limitations
imposed by shallow repositories.

If the source repository is shallow, fetch as much as possible so
that the current repository has the same history as the source
repository.

--update-shallow
By default when fetching from a shallow repository, git fetch
refuses refs that require updating .git/shallow. This option
updates .git/shallow and accepts such refs.

--negotiation-tip=<commit|glob>
By default, Git will report, to the server, commits reachable
from all local refs to find common commits in an attempt to
reduce the size of the to-be-received packfile. If specified, Git
will only report commits reachable from the given tips. This is
useful to speed up fetches when the user knows which local ref is
likely to have commits in common with the upstream ref being
fetched.

This option may be specified more than once; if so, Git will
report commits reachable from any of the given commits.

The argument to this option may be a glob on ref names, a ref, or
the (possibly abbreviated) SHA-1 of a commit. Specifying a glob
is equivalent to specifying this option multiple times, one for
each matching ref name.

See also the fetch.negotiationAlgorithm and push.negotiate
configuration variables documented in git-config(1), and the
--negotiate-only option below.

--negotiate-only
Do not fetch anything from the server, and instead print the
ancestors of the provided --negotiation-tip=* arguments, which we
have in common with the server.

This is incompatible with --recurse-submodules=[yes|on-demand].
Internally this is used to implement the push.negotiate option,
see git-config(1).

--dry-run
Show what would be done, without making any changes.

--porcelain
Print the output to standard output in an easy-to-parse format
for scripts. See section OUTPUT in git-fetch(1) for details.

This is incompatible with --recurse-submodules=[yes|on-demand]
and takes precedence over the fetch.output config option.

-f, --force
When git fetch is used with <src>:<dst> refspec, it may refuse to
update the local branch as discussed in the <refspec> part of the
git-fetch(1) documentation. This option overrides that check.

-k, --keep
Keep downloaded pack.

--prefetch
Modify the configured refspec to place all refs into the
refs/prefetch/ namespace. See the prefetch task in git-
maintenance(1).

-p, --prune
Before fetching, remove any remote-tracking references that no
longer exist on the remote. Tags are not subject to pruning if
they are fetched only because of the default tag auto-following
or due to a --tags option. However, if tags are fetched due to an
explicit refspec (either on the command line or in the remote
configuration, for example if the remote was cloned with the
--mirror option), then they are also subject to pruning.
Supplying --prune-tags is a shorthand for providing the tag
refspec.

--no-tags
By default, tags that point at objects that are downloaded from
the remote repository are fetched and stored locally. This option
disables this automatic tag following. The default behavior for a
remote may be specified with the remote.<name>.tagOpt setting.
See git-config(1).

--refmap=<refspec>
When fetching refs listed on the command line, use the specified
refspec (can be given more than once) to map the refs to
remote-tracking branches, instead of the values of remote.*.fetch
configuration variables for the remote repository. Providing an
empty <refspec> to the --refmap option causes Git to ignore the
configured refspecs and rely entirely on the refspecs supplied as
command-line arguments. See section on "Configured
Remote-tracking Branches" for details.

-t, --tags
Fetch all tags from the remote (i.e., fetch remote tags
refs/tags/* into local tags with the same name), in addition to
whatever else would otherwise be fetched. Using this option alone
does not subject tags to pruning, even if --prune is used (though
tags may be pruned anyway if they are also the destination of an
explicit refspec; see --prune).

-j, --jobs=<n>
Number of parallel children to be used for all forms of fetching.

If the --multiple option was specified, the different remotes
will be fetched in parallel. If multiple submodules are fetched,
they will be fetched in parallel. To control them independently,
use the config settings fetch.parallel and submodule.fetchJobs
(see git-config(1)).

Typically, parallel recursive and multi-remote fetches will be
faster. By default fetches are performed sequentially, not in
parallel.

--set-upstream
If the remote is fetched successfully, add upstream (tracking)
reference, used by argument-less git-pull(1) and other commands.
For more information, see branch.<name>.merge and
branch.<name>.remote in git-config(1).

--upload-pack <upload-pack>
When given, and the repository to fetch from is handled by git
fetch-pack, --exec=<upload-pack> is passed to the command to
specify non-default path for the command run on the other end.

--progress
Progress status is reported on the standard error stream by
default when it is attached to a terminal, unless -q is
specified. This flag forces progress status even if the standard
error stream is not directed to a terminal.

-o <option>, --server-option=<option>
Transmit the given string to the server when communicating using
protocol version 2. The given string must not contain a NUL or LF
character. The server's handling of server options, including
unknown ones, is server-specific. When multiple
--server-option=<option> are given, they are all sent to the
other side in the order listed on the command line. When no
--server-option=<option> is given from the command line, the
values of configuration variable remote.<name>.serverOption are
used instead.

--show-forced-updates
By default, git checks if a branch is force-updated during fetch.
This can be disabled through fetch.showForcedUpdates, but the
--show-forced-updates option guarantees this check occurs. See
git-config(1).

--no-show-forced-updates
By default, git checks if a branch is force-updated during fetch.
Pass --no-show-forced-updates or set fetch.showForcedUpdates to
false to skip this check for performance reasons. If used during
git-pull the --ff-only option will still check for forced updates
before attempting a fast-forward update. See git-config(1).

-4, --ipv4
Use IPv4 addresses only, ignoring IPv6 addresses.

-6, --ipv6
Use IPv6 addresses only, ignoring IPv4 addresses.

<repository>
The "remote" repository that is the source of a fetch or pull
operation. This parameter can be either a URL (see the section
GIT URLS below) or the name of a remote (see the section REMOTES
below).

<refspec>
Specifies which refs to fetch and which local refs to update.
When no <refspec>s appear on the command line, the refs to fetch
are read from remote.<repository>.fetch variables instead (see
the section "CONFIGURED REMOTE-TRACKING BRANCHES" in git-
fetch(1)).

The format of a <refspec> parameter is an optional plus +,
followed by the source <src>, followed by a colon :, followed by
the destination <dst>. The colon can be omitted when <dst> is
empty. <src> is typically a ref, or a glob pattern with a single
* that is used to match a set of refs, but it can also be a fully
spelled hex object name.

A <refspec> may contain a * in its <src> to indicate a simple
pattern match. Such a refspec functions like a glob that matches
any ref with the pattern. A pattern <refspec> must have one and
only one * in both the <src> and <dst>. It will map refs to the
destination by replacing the * with the contents matched from the
source.

If a refspec is prefixed by ^, it will be interpreted as a
negative refspec. Rather than specifying which refs to fetch or
which local refs to update, such a refspec will instead specify
refs to exclude. A ref will be considered to match if it matches
at least one positive refspec, and does not match any negative
refspec. Negative refspecs can be useful to restrict the scope of
a pattern refspec so that it will not include specific refs.
Negative refspecs can themselves be pattern refspecs. However,
they may only contain a <src> and do not specify a <dst>. Fully
spelled out hex object names are also not supported.

tag <tag> means the same as refs/tags/<tag>:refs/tags/<tag>; it
requests fetching everything up to the given tag.

The remote ref that matches <src> is fetched, and if <dst> is not
an empty string, an attempt is made to update the local ref that
matches it.

Whether that update is allowed without --force depends on the ref
namespace it's being fetched to, the type of object being
fetched, and whether the update is considered to be a
fast-forward. Generally, the same rules apply for fetching as
when pushing, see the <refspec>... section of git-push(1) for
what those are. Exceptions to those rules particular to git fetch
are noted below.

Until Git version 2.20, and unlike when pushing with git-push(1),
any updates to refs/tags/* would be accepted without + in the
refspec (or --force). When fetching, we promiscuously considered
all tag updates from a remote to be forced fetches. Since Git
version 2.20, fetching to update refs/tags/* works the same way
as when pushing. I.e. any updates will be rejected without + in
the refspec (or --force).

Unlike when pushing with git-push(1), any updates outside of
refs/{tags,heads}/* will be accepted without + in the refspec (or
--force), whether that's swapping e.g. a tree object for a blob,
or a commit for another commit that doesn't have the previous
commit as an ancestor etc.

Unlike when pushing with git-push(1), there is no configuration
which'll amend these rules, and nothing like a pre-fetch hook
analogous to the pre-receive hook.

As with pushing with git-push(1), all of the rules described
above about what's not allowed as an update can be overridden by
adding an optional leading + to a refspec (or using the --force
command line option). The only exception to this is that no
amount of forcing will make the refs/heads/* namespace accept a
non-commit object.

Note
When the remote branch you want to fetch is known to be
rewound and rebased regularly, it is expected that its new
tip will not be a descendant of its previous tip (as stored
in your remote-tracking branch the last time you fetched).
You would want to use the + sign to indicate non-fast-forward
updates will be needed for such branches. There is no way to
determine or declare that a branch will be made available in
a repository with this behavior; the pulling user simply must
know this is the expected usage pattern for a branch.

Note
There is a difference between listing multiple <refspec>
directly on git pull command line and having multiple
remote.<repository>.fetch entries in your configuration for a
<repository> and running a git pull command without any
explicit <refspec> parameters. <refspec>s listed explicitly
on the command line are always merged into the current branch
after fetching. In other words, if you list more than one
remote ref, git pull will create an Octopus merge. On the
other hand, if you do not list any explicit <refspec>
parameter on the command line, git pull will fetch all the
<refspec>s it finds in the remote.<repository>.fetch
configuration and merge only the first <refspec> found into
the current branch. This is because making an Octopus from
remote refs is rarely done, while keeping track of multiple
remote heads in one-go by fetching more than one is often
useful.

GIT URLS

In general, URLs contain information about the transport protocol,
the address of the remote server, and the path to the repository.
Depending on the transport protocol, some of this information may be
absent.

Git supports ssh, git, http, and https protocols (in addition, ftp
and ftps can be used for fetching, but this is inefficient and
deprecated; do not use them).

The native transport (i.e. git:// URL) does no authentication and
should be used with caution on unsecured networks.

The following syntaxes may be used with them:

+o ssh://[<user>@]<host>[:<port>]/<path-to-git-repo>

+o git://<host>[:<port>]/<path-to-git-repo>

+o http[s]://<host>[:<port>]/<path-to-git-repo>

+o ftp[s]://<host>[:<port>]/<path-to-git-repo>

An alternative scp-like syntax may also be used with the ssh
protocol:

+o [<user>@]<host>:/<path-to-git-repo>

This syntax is only recognized if there are no slashes before the
first colon. This helps differentiate a local path that contains a
colon. For example the local path foo:bar could be specified as an
absolute path or ./foo:bar to avoid being misinterpreted as an ssh
url.

The ssh and git protocols additionally support ~<username> expansion:

+o ssh://[<user>@]<host>[:<port>]/~<user>/<path-to-git-repo>

+o git://<host>[:<port>]/~<user>/<path-to-git-repo>

+o [<user>@]<host>:~<user>/<path-to-git-repo>

For local repositories, also supported by Git natively, the following
syntaxes may be used:

+o /path/to/repo.git/

+o file:///path/to/repo.git/

These two syntaxes are mostly equivalent, except when cloning, when
the former implies --local option. See git-clone(1) for details.

git clone, git fetch and git pull, but not git push, will also accept
a suitable bundle file. See git-bundle(1).

When Git doesn't know how to handle a certain transport protocol, it
attempts to use the remote-<transport> remote helper, if one exists.
To explicitly request a remote helper, the following syntax may be
used:

+o <transport>::<address>

where <address> may be a path, a server and path, or an arbitrary
URL-like string recognized by the specific remote helper being
invoked. See gitremote-helpers(7) for details.

If there are a large number of similarly-named remote repositories
and you want to use a different format for them (such that the URLs
you use will be rewritten into URLs that work), you can create a
configuration section of the form:

[url "<actual-url-base>"]
insteadOf = <other-url-base>

For example, with this:

[url "git://git.host.xz/"]
insteadOf = host.xz:/path/to/
insteadOf = work:

a URL like "work:repo.git" or like "host.xz:/path/to/repo.git" will
be rewritten in any context that takes a URL to be
"git://git.host.xz/repo.git".

If you want to rewrite URLs for push only, you can create a
configuration section of the form:

[url "<actual-url-base>"]
pushInsteadOf = <other-url-base>

For example, with this:

[url "ssh://example.org/"]
pushInsteadOf = git://example.org/

a URL like "git://example.org/path/to/repo.git" will be rewritten to
"ssh://example.org/path/to/repo.git" for pushes, but pulls will still
use the original URL.

REMOTES

The name of one of the following can be used instead of a URL as
<repository> argument:

+o a remote in the Git configuration file: $GIT_DIR/config,

+o a file in the $GIT_DIR/remotes directory, or

+o a file in the $GIT_DIR/branches directory.

All of these also allow you to omit the refspec from the command line
because they each contain a refspec which git will use by default.

Named remote in configuration file

You can choose to provide the name of a remote which you had
previously configured using git-remote(1), git-config(1) or even by a
manual edit to the $GIT_DIR/config file. The URL of this remote will
be used to access the repository. The refspec of this remote will be
used by default when you do not provide a refspec on the command
line. The entry in the config file would appear like this:

[remote "<name>"]
url = <URL>
pushurl = <pushurl>
push = <refspec>
fetch = <refspec>

The <pushurl> is used for pushes only. It is optional and defaults to
<URL>. Pushing to a remote affects all defined pushurls or all
defined urls if no pushurls are defined. Fetch, however, will only
fetch from the first defined url if multiple urls are defined.

Named file in $GIT_DIR/remotes
You can choose to provide the name of a file in $GIT_DIR/remotes. The
URL in this file will be used to access the repository. The refspec
in this file will be used as default when you do not provide a
refspec on the command line. This file should have the following
format:

URL: one of the above URL formats
Push: <refspec>
Pull: <refspec>

Push: lines are used by git push and Pull: lines are used by git pull
and git fetch. Multiple Push: and Pull: lines may be specified for
additional branch mappings.

Named file in $GIT_DIR/branches
You can choose to provide the name of a file in $GIT_DIR/branches.
The URL in this file will be used to access the repository. This file
should have the following format:

<URL>#<head>

<URL> is required; #<head> is optional.

Depending on the operation, git will use one of the following
refspecs, if you don't provide one on the command line. <branch> is
the name of this file in $GIT_DIR/branches and <head> defaults to
master.

git fetch uses:

refs/heads/<head>:refs/heads/<branch>

git push uses:

HEAD:refs/heads/<head>

MERGE STRATEGIES

The merge mechanism (git merge and git pull commands) allows the
backend merge strategies to be chosen with -s option. Some strategies
can also take their own options, which can be passed by giving
-X<option> arguments to git merge and/or git pull.

ort
This is the default merge strategy when pulling or merging one
branch. This strategy can only resolve two heads using a 3-way
merge algorithm. When there is more than one common ancestor that
can be used for 3-way merge, it creates a merged tree of the
common ancestors and uses that as the reference tree for the
3-way merge. This has been reported to result in fewer merge
conflicts without causing mismerges by tests done on actual merge
commits taken from Linux 2.6 kernel development history.
Additionally this strategy can detect and handle merges involving
renames. It does not make use of detected copies. The name for
this algorithm is an acronym ("Ostensibly Recursive's Twin") and
came from the fact that it was written as a replacement for the
previous default algorithm, recursive.

The ort strategy can take the following options:

ours
This option forces conflicting hunks to be auto-resolved
cleanly by favoring our version. Changes from the other tree
that do not conflict with our side are reflected in the merge
result. For a binary file, the entire contents are taken from
our side.

This should not be confused with the ours merge strategy,
which does not even look at what the other tree contains at
all. It discards everything the other tree did, declaring our
history contains all that happened in it.

theirs
This is the opposite of ours; note that, unlike ours, there
is no theirs merge strategy to confuse this merge option
with.

ignore-space-change, ignore-all-space, ignore-space-at-eol,
ignore-cr-at-eol
Treats lines with the indicated type of whitespace change as
unchanged for the sake of a three-way merge. Whitespace
changes mixed with other changes to a line are not ignored.
See also git-diff(1) -b, -w, --ignore-space-at-eol, and
--ignore-cr-at-eol.

+o If their version only introduces whitespace changes to a
line, our version is used;

+o If our version introduces whitespace changes but their
version includes a substantial change, their version is
used;

+o Otherwise, the merge proceeds in the usual way.

renormalize
This runs a virtual check-out and check-in of all three
stages of a file when resolving a three-way merge. This
option is meant to be used when merging branches with
different clean filters or end-of-line normalization rules.
See "Merging branches with differing checkin/checkout
attributes" in gitattributes(5) for details.

no-renormalize
Disables the renormalize option. This overrides the
merge.renormalize configuration variable.

find-renames[=<n>]
Turn on rename detection, optionally setting the similarity
threshold. This is the default. This overrides the
merge.renames configuration variable. See also git-diff(1)
--find-renames.

rename-threshold=<n>
Deprecated synonym for find-renames=<n>.

subtree[=<path>]
This option is a more advanced form of subtree strategy,
where the strategy makes a guess on how two trees must be
shifted to match with each other when merging. Instead, the
specified path is prefixed (or stripped from the beginning)
to make the shape of two trees to match.

recursive
This can only resolve two heads using a 3-way merge algorithm.
When there is more than one common ancestor that can be used for
3-way merge, it creates a merged tree of the common ancestors and
uses that as the reference tree for the 3-way merge. This has
been reported to result in fewer merge conflicts without causing
mismerges by tests done on actual merge commits taken from Linux
2.6 kernel development history. Additionally this can detect and
handle merges involving renames. It does not make use of detected
copies. This was the default strategy for resolving two heads
from Git v0.99.9k until v2.33.0.

The recursive strategy takes the same options as ort. However,
there are three additional options that ort ignores (not
documented above) that are potentially useful with the recursive
strategy:

patience
Deprecated synonym for diff-algorithm=patience.

diff-algorithm=[patience|minimal|histogram|myers]
Use a different diff algorithm while merging, which can help
avoid mismerges that occur due to unimportant matching lines
(such as braces from distinct functions). See also git-
diff(1) --diff-algorithm. Note that ort specifically uses
diff-algorithm=histogram, while recursive defaults to the
diff.algorithm config setting.

no-renames
Turn off rename detection. This overrides the merge.renames
configuration variable. See also git-diff(1) --no-renames.

resolve
This can only resolve two heads (i.e. the current branch and
another branch you pulled from) using a 3-way merge algorithm. It
tries to carefully detect criss-cross merge ambiguities. It does
not handle renames.

octopus
This resolves cases with more than two heads, but refuses to do a
complex merge that needs manual resolution. It is primarily meant
to be used for bundling topic branch heads together. This is the
default merge strategy when pulling or merging more than one
branch.

ours
This resolves any number of heads, but the resulting tree of the
merge is always that of the current branch head, effectively
ignoring all changes from all other branches. It is meant to be
used to supersede old development history of side branches. Note
that this is different from the -Xours option to the recursive
merge strategy.

subtree
This is a modified ort strategy. When merging trees A and B, if B
corresponds to a subtree of A, B is first adjusted to match the
tree structure of A, instead of reading the trees at the same
level. This adjustment is also done to the common ancestor tree.

With the strategies that use 3-way merge (including the default,
ort), if a change is made on both branches, but later reverted on one
of the branches, that change will be present in the merged result;
some people find this behavior confusing. It occurs because only the
heads and the merge base are considered when performing a merge, not
the individual commits. The merge algorithm therefore considers the
reverted change as no change at all, and substitutes the changed
version instead.

DEFAULT BEHAVIOUR

Often people use git pull without giving any parameter.
Traditionally, this has been equivalent to saying git pull origin.
However, when configuration branch.<name>.remote is present while on
branch <name>, that value is used instead of origin.

In order to determine what URL to use to fetch from, the value of the
configuration remote.<origin>.url is consulted and if there is not
any such variable, the value on the URL: line in
$GIT_DIR/remotes/<origin> is used.

In order to determine what remote branches to fetch (and optionally
store in the remote-tracking branches) when the command is run
without any refspec parameters on the command line, values of the
configuration variable remote.<origin>.fetch are consulted, and if
there aren't any, $GIT_DIR/remotes/<origin> is consulted and its
Pull: lines are used. In addition to the refspec formats described in
the OPTIONS section, you can have a globbing refspec that looks like
this:

refs/heads/*:refs/remotes/origin/*

A globbing refspec must have a non-empty RHS (i.e. must store what
were fetched in remote-tracking branches), and its LHS and RHS must
end with /*. The above specifies that all remote branches are tracked
using remote-tracking branches in refs/remotes/origin/ hierarchy
under the same name.

The rule to determine which remote branch to merge after fetching is
a bit involved, in order not to break backward compatibility.

If explicit refspecs were given on the command line of git pull, they
are all merged.

When no refspec was given on the command line, then git pull uses the
refspec from the configuration or $GIT_DIR/remotes/<origin>. In such
cases, the following rules apply:

1. If branch.<name>.merge configuration for the current branch
<name> exists, that is the name of the branch at the remote site
that is merged.

2. If the refspec is a globbing one, nothing is merged.

3. Otherwise the remote branch of the first refspec is merged.

EXAMPLES

+o Update the remote-tracking branches for the repository you cloned
from, then merge one of them into your current branch:

$ git pull
$ git pull origin

Normally the branch merged in is the HEAD of the remote
repository, but the choice is determined by the
branch.<name>.remote and branch.<name>.merge options; see git-
config(1) for details.

+o Merge into the current branch the remote branch next:

$ git pull origin next

This leaves a copy of next temporarily in FETCH_HEAD, and updates
the remote-tracking branch origin/next. The same can be done by
invoking fetch and merge:

$ git fetch origin
$ git merge origin/next

If you tried a pull which resulted in complex conflicts and would
want to start over, you can recover with git reset.

SECURITY

The fetch and push protocols are not designed to prevent one side
from stealing data from the other repository that was not intended to
be shared. If you have private data that you need to protect from a
malicious peer, your best option is to store it in another
repository. This applies to both clients and servers. In particular,
namespaces on a server are not effective for read access control; you
should only grant read access to a namespace to clients that you
would trust with read access to the entire repository.

The known attack vectors are as follows:

1. The victim sends "have" lines advertising the IDs of objects it
has that are not explicitly intended to be shared but can be used
to optimize the transfer if the peer also has them. The attacker
chooses an object ID X to steal and sends a ref to X, but isn't
required to send the content of X because the victim already has
it. Now the victim believes that the attacker has X, and it sends
the content of X back to the attacker later. (This attack is most
straightforward for a client to perform on a server, by creating
a ref to X in the namespace the client has access to and then
fetching it. The most likely way for a server to perform it on a
client is to "merge" X into a public branch and hope that the
user does additional work on this branch and pushes it back to
the server without noticing the merge.)

2. As in #1, the attacker chooses an object ID X to steal. The
victim sends an object Y that the attacker already has, and the
attacker falsely claims to have X and not Y, so the victim sends
Y as a delta against X. The delta reveals regions of X that are
similar to Y to the attacker.

BUGS

Using --recurse-submodules can only fetch new commits in already
checked out submodules right now. When e.g. upstream added a new
submodule in the just fetched commits of the superproject the
submodule itself cannot be fetched, making it impossible to check out
that submodule later without having to do a fetch again. This is
expected to be fixed in a future Git version.

SEE ALSO

git-fetch(1), git-merge(1), git-config(1)

GIT

Part of the git(1) suite

Git 2.48.1 2025-01-13 GIT-PULL(1)