diff options
Diffstat (limited to 'third_party/git/Documentation/git-checkout.txt')
-rw-r--r-- | third_party/git/Documentation/git-checkout.txt | 602 |
1 files changed, 602 insertions, 0 deletions
diff --git a/third_party/git/Documentation/git-checkout.txt b/third_party/git/Documentation/git-checkout.txt new file mode 100644 index 000000000000..c8fb995fa74e --- /dev/null +++ b/third_party/git/Documentation/git-checkout.txt @@ -0,0 +1,602 @@ +git-checkout(1) +=============== + +NAME +---- +git-checkout - Switch branches or restore working tree files + +SYNOPSIS +-------- +[verse] +'git checkout' [-q] [-f] [-m] [<branch>] +'git checkout' [-q] [-f] [-m] --detach [<branch>] +'git checkout' [-q] [-f] [-m] [--detach] <commit> +'git checkout' [-q] [-f] [-m] [[-b|-B|--orphan] <new_branch>] [<start_point>] +'git checkout' [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <pathspec>... +'git checkout' [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] --pathspec-from-file=<file> [--pathspec-file-nul] +'git checkout' (-p|--patch) [<tree-ish>] [--] [<pathspec>...] + +DESCRIPTION +----------- +Updates files in the working tree to match the version in the index +or the specified tree. If no pathspec was given, 'git checkout' will +also update `HEAD` to set the specified branch as the current +branch. + +'git checkout' [<branch>]:: + To prepare for working on `<branch>`, switch to it by updating + the index and the files in the working tree, and by pointing + `HEAD` at the branch. Local modifications to the files in the + working tree are kept, so that they can be committed to the + `<branch>`. ++ +If `<branch>` is not found but there does exist a tracking branch in +exactly one remote (call it `<remote>`) with a matching name and +`--no-guess` is not specified, treat as equivalent to ++ +------------ +$ git checkout -b <branch> --track <remote>/<branch> +------------ ++ +You could omit `<branch>`, in which case the command degenerates to +"check out the current branch", which is a glorified no-op with +rather expensive side-effects to show only the tracking information, +if exists, for the current branch. + +'git checkout' -b|-B <new_branch> [<start point>]:: + + Specifying `-b` causes a new branch to be created as if + linkgit:git-branch[1] were called and then checked out. In + this case you can use the `--track` or `--no-track` options, + which will be passed to 'git branch'. As a convenience, + `--track` without `-b` implies branch creation; see the + description of `--track` below. ++ +If `-B` is given, `<new_branch>` is created if it doesn't exist; otherwise, it +is reset. This is the transactional equivalent of ++ +------------ +$ git branch -f <branch> [<start point>] +$ git checkout <branch> +------------ ++ +that is to say, the branch is not reset/created unless "git checkout" is +successful. + +'git checkout' --detach [<branch>]:: +'git checkout' [--detach] <commit>:: + + Prepare to work on top of `<commit>`, by detaching `HEAD` at it + (see "DETACHED HEAD" section), and updating the index and the + files in the working tree. Local modifications to the files + in the working tree are kept, so that the resulting working + tree will be the state recorded in the commit plus the local + modifications. ++ +When the `<commit>` argument is a branch name, the `--detach` option can +be used to detach `HEAD` at the tip of the branch (`git checkout +<branch>` would check out that branch without detaching `HEAD`). ++ +Omitting `<branch>` detaches `HEAD` at the tip of the current branch. + +'git checkout' [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <pathspec>...:: +'git checkout' [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] --pathspec-from-file=<file> [--pathspec-file-nul]:: + + Overwrite the contents of the files that match the pathspec. + When the `<tree-ish>` (most often a commit) is not given, + overwrite working tree with the contents in the index. + When the `<tree-ish>` is given, overwrite both the index and + the working tree with the contents at the `<tree-ish>`. ++ +The index may contain unmerged entries because of a previous failed merge. +By default, if you try to check out such an entry from the index, the +checkout operation will fail and nothing will be checked out. +Using `-f` will ignore these unmerged entries. The contents from a +specific side of the merge can be checked out of the index by +using `--ours` or `--theirs`. With `-m`, changes made to the working tree +file can be discarded to re-create the original conflicted merge result. + +'git checkout' (-p|--patch) [<tree-ish>] [--] [<pathspec>...]:: + This is similar to the previous mode, but lets you use the + interactive interface to show the "diff" output and choose which + hunks to use in the result. See below for the description of + `--patch` option. + +OPTIONS +------- +-q:: +--quiet:: + Quiet, suppress feedback messages. + +--progress:: +--no-progress:: + Progress status is reported on the standard error stream + by default when it is attached to a terminal, unless `--quiet` + is specified. This flag enables progress reporting even if not + attached to a terminal, regardless of `--quiet`. + +-f:: +--force:: + When switching branches, proceed even if the index or the + working tree differs from `HEAD`. This is used to throw away + local changes. ++ +When checking out paths from the index, do not fail upon unmerged +entries; instead, unmerged entries are ignored. + +--ours:: +--theirs:: + When checking out paths from the index, check out stage #2 + ('ours') or #3 ('theirs') for unmerged paths. ++ +Note that during `git rebase` and `git pull --rebase`, 'ours' and +'theirs' may appear swapped; `--ours` gives the version from the +branch the changes are rebased onto, while `--theirs` gives the +version from the branch that holds your work that is being rebased. ++ +This is because `rebase` is used in a workflow that treats the +history at the remote as the shared canonical one, and treats the +work done on the branch you are rebasing as the third-party work to +be integrated, and you are temporarily assuming the role of the +keeper of the canonical history during the rebase. As the keeper of +the canonical history, you need to view the history from the remote +as `ours` (i.e. "our shared canonical history"), while what you did +on your side branch as `theirs` (i.e. "one contributor's work on top +of it"). + +-b <new_branch>:: + Create a new branch named `<new_branch>` and start it at + `<start_point>`; see linkgit:git-branch[1] for details. + +-B <new_branch>:: + Creates the branch `<new_branch>` and start it at `<start_point>`; + if it already exists, then reset it to `<start_point>`. This is + equivalent to running "git branch" with "-f"; see + linkgit:git-branch[1] for details. + +-t:: +--track:: + When creating a new branch, set up "upstream" configuration. See + "--track" in linkgit:git-branch[1] for details. ++ +If no `-b` option is given, the name of the new branch will be +derived from the remote-tracking branch, by looking at the local part of +the refspec configured for the corresponding remote, and then stripping +the initial part up to the "*". +This would tell us to use `hack` as the local branch when branching +off of `origin/hack` (or `remotes/origin/hack`, or even +`refs/remotes/origin/hack`). If the given name has no slash, or the above +guessing results in an empty name, the guessing is aborted. You can +explicitly give a name with `-b` in such a case. + +--no-track:: + Do not set up "upstream" configuration, even if the + `branch.autoSetupMerge` configuration variable is true. + +--guess:: +--no-guess:: + If `<branch>` is not found but there does exist a tracking + branch in exactly one remote (call it `<remote>`) with a + matching name, treat as equivalent to ++ +------------ +$ git checkout -b <branch> --track <remote>/<branch> +------------ ++ +If the branch exists in multiple remotes and one of them is named by +the `checkout.defaultRemote` configuration variable, we'll use that +one for the purposes of disambiguation, even if the `<branch>` isn't +unique across all remotes. Set it to +e.g. `checkout.defaultRemote=origin` to always checkout remote +branches from there if `<branch>` is ambiguous but exists on the +'origin' remote. See also `checkout.defaultRemote` in +linkgit:git-config[1]. ++ +Use `--no-guess` to disable this. + +-l:: + Create the new branch's reflog; see linkgit:git-branch[1] for + details. + +--detach:: + Rather than checking out a branch to work on it, check out a + commit for inspection and discardable experiments. + This is the default behavior of `git checkout <commit>` when + `<commit>` is not a branch name. See the "DETACHED HEAD" section + below for details. + +--orphan <new_branch>:: + Create a new 'orphan' branch, named `<new_branch>`, started from + `<start_point>` and switch to it. The first commit made on this + new branch will have no parents and it will be the root of a new + history totally disconnected from all the other branches and + commits. ++ +The index and the working tree are adjusted as if you had previously run +`git checkout <start_point>`. This allows you to start a new history +that records a set of paths similar to `<start_point>` by easily running +`git commit -a` to make the root commit. ++ +This can be useful when you want to publish the tree from a commit +without exposing its full history. You might want to do this to publish +an open source branch of a project whose current tree is "clean", but +whose full history contains proprietary or otherwise encumbered bits of +code. ++ +If you want to start a disconnected history that records a set of paths +that is totally different from the one of `<start_point>`, then you should +clear the index and the working tree right after creating the orphan +branch by running `git rm -rf .` from the top level of the working tree. +Afterwards you will be ready to prepare your new files, repopulating the +working tree, by copying them from elsewhere, extracting a tarball, etc. + +--ignore-skip-worktree-bits:: + In sparse checkout mode, `git checkout -- <paths>` would + update only entries matched by `<paths>` and sparse patterns + in `$GIT_DIR/info/sparse-checkout`. This option ignores + the sparse patterns and adds back any files in `<paths>`. + +-m:: +--merge:: + When switching branches, + if you have local modifications to one or more files that + are different between the current branch and the branch to + which you are switching, the command refuses to switch + branches in order to preserve your modifications in context. + However, with this option, a three-way merge between the current + branch, your working tree contents, and the new branch + is done, and you will be on the new branch. ++ +When a merge conflict happens, the index entries for conflicting +paths are left unmerged, and you need to resolve the conflicts +and mark the resolved paths with `git add` (or `git rm` if the merge +should result in deletion of the path). ++ +When checking out paths from the index, this option lets you recreate +the conflicted merge in the specified paths. ++ +When switching branches with `--merge`, staged changes may be lost. + +--conflict=<style>:: + The same as `--merge` option above, but changes the way the + conflicting hunks are presented, overriding the + `merge.conflictStyle` configuration variable. Possible values are + "merge" (default) and "diff3" (in addition to what is shown by + "merge" style, shows the original contents). + +-p:: +--patch:: + Interactively select hunks in the difference between the + `<tree-ish>` (or the index, if unspecified) and the working + tree. The chosen hunks are then applied in reverse to the + working tree (and if a `<tree-ish>` was specified, the index). ++ +This means that you can use `git checkout -p` to selectively discard +edits from your current working tree. See the ``Interactive Mode'' +section of linkgit:git-add[1] to learn how to operate the `--patch` mode. ++ +Note that this option uses the no overlay mode by default (see also +`--overlay`), and currently doesn't support overlay mode. + +--ignore-other-worktrees:: + `git checkout` refuses when the wanted ref is already checked + out by another worktree. This option makes it check the ref + out anyway. In other words, the ref can be held by more than one + worktree. + +--overwrite-ignore:: +--no-overwrite-ignore:: + Silently overwrite ignored files when switching branches. This + is the default behavior. Use `--no-overwrite-ignore` to abort + the operation when the new branch contains ignored files. + +--recurse-submodules:: +--no-recurse-submodules:: + Using `--recurse-submodules` will update the content of all initialized + submodules according to the commit recorded in the superproject. If + local modifications in a submodule would be overwritten the checkout + will fail unless `-f` is used. If nothing (or `--no-recurse-submodules`) + is used, the work trees of submodules will not be updated. + Just like linkgit:git-submodule[1], this will detach `HEAD` of the + submodule. + +--overlay:: +--no-overlay:: + In the default overlay mode, `git checkout` never + removes files from the index or the working tree. When + specifying `--no-overlay`, files that appear in the index and + working tree, but not in `<tree-ish>` are removed, to make them + match `<tree-ish>` exactly. + +--pathspec-from-file=<file>:: + Pathspec is passed in `<file>` instead of commandline args. If + `<file>` is exactly `-` then standard input is used. Pathspec + elements are separated by LF or CR/LF. Pathspec elements can be + quoted as explained for the configuration variable `core.quotePath` + (see linkgit:git-config[1]). See also `--pathspec-file-nul` and + global `--literal-pathspecs`. + +--pathspec-file-nul:: + Only meaningful with `--pathspec-from-file`. Pathspec elements are + separated with NUL character and all other characters are taken + literally (including newlines and quotes). + +<branch>:: + Branch to checkout; if it refers to a branch (i.e., a name that, + when prepended with "refs/heads/", is a valid ref), then that + branch is checked out. Otherwise, if it refers to a valid + commit, your `HEAD` becomes "detached" and you are no longer on + any branch (see below for details). ++ +You can use the `@{-N}` syntax to refer to the N-th last +branch/commit checked out using "git checkout" operation. You may +also specify `-` which is synonymous to `@{-1}`. ++ +As a special case, you may use `A...B` as a shortcut for the +merge base of `A` and `B` if there is exactly one merge base. You can +leave out at most one of `A` and `B`, in which case it defaults to `HEAD`. + +<new_branch>:: + Name for the new branch. + +<start_point>:: + The name of a commit at which to start the new branch; see + linkgit:git-branch[1] for details. Defaults to `HEAD`. ++ +As a special case, you may use `"A...B"` as a shortcut for the +merge base of `A` and `B` if there is exactly one merge base. You can +leave out at most one of `A` and `B`, in which case it defaults to `HEAD`. + +<tree-ish>:: + Tree to checkout from (when paths are given). If not specified, + the index will be used. + +\--:: + Do not interpret any more arguments as options. + +<pathspec>...:: + Limits the paths affected by the operation. ++ +For more details, see the 'pathspec' entry in linkgit:gitglossary[7]. + +DETACHED HEAD +------------- +`HEAD` normally refers to a named branch (e.g. `master`). Meanwhile, each +branch refers to a specific commit. Let's look at a repo with three +commits, one of them tagged, and with branch `master` checked out: + +------------ + HEAD (refers to branch 'master') + | + v +a---b---c branch 'master' (refers to commit 'c') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +When a commit is created in this state, the branch is updated to refer to +the new commit. Specifically, 'git commit' creates a new commit `d`, whose +parent is commit `c`, and then updates branch `master` to refer to new +commit `d`. `HEAD` still refers to branch `master` and so indirectly now refers +to commit `d`: + +------------ +$ edit; git add; git commit + + HEAD (refers to branch 'master') + | + v +a---b---c---d branch 'master' (refers to commit 'd') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +It is sometimes useful to be able to checkout a commit that is not at +the tip of any named branch, or even to create a new commit that is not +referenced by a named branch. Let's look at what happens when we +checkout commit `b` (here we show two ways this may be done): + +------------ +$ git checkout v2.0 # or +$ git checkout master^^ + + HEAD (refers to commit 'b') + | + v +a---b---c---d branch 'master' (refers to commit 'd') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +Notice that regardless of which checkout command we use, `HEAD` now refers +directly to commit `b`. This is known as being in detached `HEAD` state. +It means simply that `HEAD` refers to a specific commit, as opposed to +referring to a named branch. Let's see what happens when we create a commit: + +------------ +$ edit; git add; git commit + + HEAD (refers to commit 'e') + | + v + e + / +a---b---c---d branch 'master' (refers to commit 'd') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +There is now a new commit `e`, but it is referenced only by `HEAD`. We can +of course add yet another commit in this state: + +------------ +$ edit; git add; git commit + + HEAD (refers to commit 'f') + | + v + e---f + / +a---b---c---d branch 'master' (refers to commit 'd') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +In fact, we can perform all the normal Git operations. But, let's look +at what happens when we then checkout `master`: + +------------ +$ git checkout master + + HEAD (refers to branch 'master') + e---f | + / v +a---b---c---d branch 'master' (refers to commit 'd') + ^ + | + tag 'v2.0' (refers to commit 'b') +------------ + +It is important to realize that at this point nothing refers to commit +`f`. Eventually commit `f` (and by extension commit `e`) will be deleted +by the routine Git garbage collection process, unless we create a reference +before that happens. If we have not yet moved away from commit `f`, +any of these will create a reference to it: + +------------ +$ git checkout -b foo <1> +$ git branch foo <2> +$ git tag foo <3> +------------ + +<1> creates a new branch `foo`, which refers to commit `f`, and then + updates `HEAD` to refer to branch `foo`. In other words, we'll no longer + be in detached `HEAD` state after this command. + +<2> similarly creates a new branch `foo`, which refers to commit `f`, + but leaves `HEAD` detached. + +<3> creates a new tag `foo`, which refers to commit `f`, + leaving `HEAD` detached. + +If we have moved away from commit `f`, then we must first recover its object +name (typically by using git reflog), and then we can create a reference to +it. For example, to see the last two commits to which `HEAD` referred, we +can use either of these commands: + +------------ +$ git reflog -2 HEAD # or +$ git log -g -2 HEAD +------------ + +ARGUMENT DISAMBIGUATION +----------------------- + +When there is only one argument given and it is not `--` (e.g. `git +checkout abc`), and when the argument is both a valid `<tree-ish>` +(e.g. a branch `abc` exists) and a valid `<pathspec>` (e.g. a file +or a directory whose name is "abc" exists), Git would usually ask +you to disambiguate. Because checking out a branch is so common an +operation, however, `git checkout abc` takes "abc" as a `<tree-ish>` +in such a situation. Use `git checkout -- <pathspec>` if you want +to checkout these paths out of the index. + +EXAMPLES +-------- + +. The following sequence checks out the `master` branch, reverts + the `Makefile` to two revisions back, deletes `hello.c` by + mistake, and gets it back from the index. ++ +------------ +$ git checkout master <1> +$ git checkout master~2 Makefile <2> +$ rm -f hello.c +$ git checkout hello.c <3> +------------ ++ +<1> switch branch +<2> take a file out of another commit +<3> restore `hello.c` from the index ++ +If you want to check out _all_ C source files out of the index, +you can say ++ +------------ +$ git checkout -- '*.c' +------------ ++ +Note the quotes around `*.c`. The file `hello.c` will also be +checked out, even though it is no longer in the working tree, +because the file globbing is used to match entries in the index +(not in the working tree by the shell). ++ +If you have an unfortunate branch that is named `hello.c`, this +step would be confused as an instruction to switch to that branch. +You should instead write: ++ +------------ +$ git checkout -- hello.c +------------ + +. After working in the wrong branch, switching to the correct + branch would be done using: ++ +------------ +$ git checkout mytopic +------------ ++ +However, your "wrong" branch and correct `mytopic` branch may +differ in files that you have modified locally, in which case +the above checkout would fail like this: ++ +------------ +$ git checkout mytopic +error: You have local changes to 'frotz'; not switching branches. +------------ ++ +You can give the `-m` flag to the command, which would try a +three-way merge: ++ +------------ +$ git checkout -m mytopic +Auto-merging frotz +------------ ++ +After this three-way merge, the local modifications are _not_ +registered in your index file, so `git diff` would show you what +changes you made since the tip of the new branch. + +. When a merge conflict happens during switching branches with + the `-m` option, you would see something like this: ++ +------------ +$ git checkout -m mytopic +Auto-merging frotz +ERROR: Merge conflict in frotz +fatal: merge program failed +------------ ++ +At this point, `git diff` shows the changes cleanly merged as in +the previous example, as well as the changes in the conflicted +files. Edit and resolve the conflict and mark it resolved with +`git add` as usual: ++ +------------ +$ edit frotz +$ git add frotz +------------ + +SEE ALSO +-------- +linkgit:git-switch[1], +linkgit:git-restore[1] + +GIT +--- +Part of the linkgit:git[1] suite |