SYNOPSIS
--------
[verse]
-'git push' [--all | --mirror | --tags] [--dry-run] [--receive-pack=<git-receive-pack>]
+'git push' [--all | --mirror | --tags] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
[--repo=<repository>] [-f | --force] [-v | --verbose]
[<repository> <refspec>...]
+
The object referenced by <src> is used to update the <dst> reference
on the remote side, but by default this is only allowed if the
-update can fast forward <dst>. By having the optional leading `{plus}`,
+update can fast-forward <dst>. By having the optional leading `{plus}`,
you can tell git to update the <dst> ref even when the update is not a
-fast forward. This does *not* attempt to merge <src> into <dst>. See
+fast-forward. This does *not* attempt to merge <src> into <dst>. See
EXAMPLES below for details.
+
`tag <tag>` means the same as `refs/tags/<tag>:refs/tags/<tag>`.
Pushing an empty <src> allows you to delete the <dst> ref from
the remote repository.
+
-The special refspec `:` (or `{plus}:` to allow non-fast forward updates)
+The special refspec `:` (or `{plus}:` to allow non-fast-forward updates)
directs git to push "matching" branches: for every branch that exists on
the local side, the remote side is updated if a branch of the same name
already exists on the remote side. This is the default operation mode
if the configuration option `remote.<remote>.mirror` is
set.
+-n::
--dry-run::
Do everything except actually send the updates.
--verbose::
Run verbosely.
+-q::
+--quiet::
+ Suppress all output, including the listing of updated refs,
+ unless an error occurs.
+
include::urls-remotes.txt[]
OUTPUT
For a successfully pushed ref, the summary shows the old and new
values of the ref in a form suitable for using as an argument to
`git log` (this is `<old>..<new>` in most cases, and
- `<old>...<new>` for forced non-fast forward updates). For a
+ `<old>...<new>` for forced non-fast-forward updates). For a
failed update, more details are given for the failure.
The string `rejected` indicates that git did not try to send the
- ref at all (typically because it is not a fast forward). The
+ ref at all (typically because it is not a fast-forward). The
string `remote rejected` indicates that the remote end refused
the update; this rejection is typically caused by a hook on the
remote side. The string `remote failure` indicates that the
refs, no explanation is needed. For a failed ref, the reason for
failure is described.
+Note about fast-forwards
+------------------------
+
+When an update changes a branch (or more in general, a ref) that used to
+point at commit A to point at another commit B, it is called a
+fast-forward update if and only if B is a descendant of A.
+
+In a fast-forward update from A to B, the set of commits that the original
+commit A built on top of is a subset of the commits the new commit B
+builds on top of. Hence, it does not lose any history.
+
+In contrast, a non-fast-forward update will lose history. For example,
+suppose you and somebody else started at the same commit X, and you built
+a history leading to commit B while the other person built a history
+leading to commit A. The history looks like this:
+
+----------------
+
+ B
+ /
+ ---X---A
+
+----------------
+
+Further suppose that the other person already pushed changes leading to A
+back to the original repository you two obtained the original commit X.
+
+The push done by the other person updated the branch that used to point at
+commit X to point at commit A. It is a fast-forward.
+
+But if you try to push, you will attempt to update the branch (that
+now points at A) with commit B. This does _not_ fast-forward. If you did
+so, the changes introduced by commit A will be lost, because everybody
+will now start building on top of B.
+
+The command by default does not allow an update that is not a fast-forward
+to prevent such loss of history.
+
+If you do not want to lose your work (history from X to B) nor the work by
+the other person (history from X to A), you would need to first fetch the
+history from the repository, create a history that contains changes done
+by both parties, and push the result back.
+
+You can perform "git pull", resolve potential conflicts, and "git push"
+the result. A "git pull" will create a merge commit C between commits A
+and B.
+
+----------------
+
+ B---C
+ / /
+ ---X---A
+
+----------------
+
+Updating A with the resulting merge commit will fast-forward and your
+push will be accepted.
+
+Alternatively, you can rebase your change between X and B on top of A,
+with "git pull --rebase", and push the result back. The rebase will
+create a new commit D that builds the change between X and B on top of
+A.
+
+----------------
+
+ B D
+ / /
+ ---X---A
+
+----------------
+
+Again, updating A with this commit will fast-forward and your push will be
+accepted.
+
+There is another common situation where you may encounter non-fast-forward
+rejection when you try to push, and it is possible even when you are
+pushing into a repository nobody else pushes into. After you push commit
+A yourself (in the first picture in this section), replace it with "git
+commit --amend" to produce commit B, and you try to push it out, because
+forgot that you have pushed A out already. In such a case, and only if
+you are certain that nobody in the meantime fetched your earlier commit A
+(and started building on top of it), you can run "git push --force" to
+overwrite it. In other words, "git push --force" is a method reserved for
+a case where you do mean to lose history.
+
+
Examples
--------
git push origin {plus}dev:master::
Update the origin repository's master branch with the dev branch,
- allowing non-fast forward updates. *This can leave unreferenced
+ allowing non-fast-forward updates. *This can leave unreferenced
commits dangling in the origin repository.* Consider the
- following situation, where a fast forward is not possible:
+ following situation, where a fast-forward is not possible:
+
----
o---o---o---A---B origin/master
projects / thirdparty / git.git / blobdiff