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git-pull (1)

Name

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

Synopsis

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

Description

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
           http://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 special 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
       --all
           Fetch all remotes.

       -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=<revision>
           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 accept 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.

       -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.

       --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 ref <dst>. The colon can be omitted when <dst> is
           empty. <src> is typically a ref, 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 same prefix. A pattern <refspec> must have a * 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's 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 the optional leading + to a refspec (or using --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 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 it).

       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.xz[:port]/path/to/repo.git/

       o   git://host.xz[:port]/path/to/repo.git/

       o   http[s]://host.xz[:port]/path/to/repo.git/

       o   ftp[s]://host.xz[:port]/path/to/repo.git/

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

       o   [user@]host.xz:path/to/repo.git/

       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.xz[:port]/~[user]/path/to/repo.git/

       o   git://host.xz[:port]/~[user]/path/to/repo.git/

       o   [user@]host.xz:/~[user]/path/to/repo.git/

       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>.

   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 format
                   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 2.36.0                        04/17/2022                       GIT-PULL(1)