Documentation/git-checkout.txt

   1 git-checkout(1)
   2 ===============
   3
   4 NAME
   5 ----
   6 git-checkout - Checkout a branch or paths to the working tree
   7
   8 SYNOPSIS
   9 --------
  10 [verse]
  11 'git checkout' [-q] [-f] [-m] [<branch>]
  12 'git checkout' [-q] [-f] [-m] [[-b|--orphan] <new_branch>] [<start_point>]
  13 'git checkout' [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <paths>...
  14 'git checkout' --patch [<tree-ish>] [--] [<paths>...]
  15
  16 DESCRIPTION
  17 -----------
  18
  19 When <paths> are not given, this command switches branches by
  20 updating the index, working tree, and HEAD to reflect the specified
  21 branch.
  22
  23 If `-b` is given, a new branch is created and checked out, as if
  24 linkgit:git-branch[1] were called; in this case you can
  25 use the --track or --no-track options, which will be passed to `git
  26 branch`.  As a convenience, --track without `-b` implies branch
  27 creation; see the description of --track below.
  28
  29 When <paths> or --patch are given, this command does *not* switch
  30 branches.  It updates the named paths in the working tree from
  31 the index file, or from a named <tree-ish> (most often a commit).  In
  32 this case, the `-b` and `--track` options are meaningless and giving
  33 either of them results in an error. The <tree-ish> argument can be
  34 used to specify a specific tree-ish (i.e. commit, tag or tree)
  35 to update the index for the given paths before updating the
  36 working tree.
  37
  38 The index may contain unmerged entries after a failed merge.  By
  39 default, if you try to check out such an entry from the index, the
  40 checkout operation will fail and nothing will be checked out.
  41 Using -f will ignore these unmerged entries.  The contents from a
  42 specific side of the merge can be checked out of the index by
  43 using --ours or --theirs.  With -m, changes made to the working tree
  44 file can be discarded to recreate the original conflicted merge result.
  45
  46 OPTIONS
  47 -------
  48 -q::
  49 --quiet::
  50         Quiet, suppress feedback messages.
  51
  52 -f::
  53 --force::
  54         When switching branches, proceed even if the index or the
  55         working tree differs from HEAD.  This is used to throw away
  56         local changes.
  57 +
  58 When checking out paths from the index, do not fail upon unmerged
  59 entries; instead, unmerged entries are ignored.
  60
  61 --ours::
  62 --theirs::
  63         When checking out paths from the index, check out stage #2
  64         ('ours') or #3 ('theirs') for unmerged paths.
  65
  66 -b::
  67         Create a new branch named <new_branch> and start it at
  68         <start_point>; see linkgit:git-branch[1] for details.
  69
  70 -t::
  71 --track::
  72         When creating a new branch, set up "upstream" configuration. See
  73         "--track" in linkgit:git-branch[1] for details.
  74 +
  75 If no '-b' option is given, the name of the new branch will be
  76 derived from the remote branch.  If "remotes/" or "refs/remotes/"
  77 is prefixed it is stripped away, and then the part up to the
  78 next slash (which would be the nickname of the remote) is removed.
  79 This would tell us to use "hack" as the local branch when branching
  80 off of "origin/hack" (or "remotes/origin/hack", or even
  81 "refs/remotes/origin/hack").  If the given name has no slash, or the above
  82 guessing results in an empty name, the guessing is aborted.  You can
  83 explicitly give a name with '-b' in such a case.
  84
  85 --no-track::
  86         Do not set up "upstream" configuration, even if the
  87         branch.autosetupmerge configuration variable is true.
  88
  89 -l::
  90         Create the new branch's reflog; see linkgit:git-branch[1] for
  91         details.
  92
  93 --orphan::
  94         Create a new branch named <new_branch>, unparented to any other
  95         branch.  The new branch you switch to does not have any commit
  96         and after the first one it will become the root of a new history
  97         completely unconnected from all the other branches.
  98 +
  99 When you use "--orphan", the index and the working tree are kept intact.
 100 This allows you to start a new history that records set of paths similar
 101 to that of the start-point commit, which is useful when you want to keep
 102 different branches for different audiences you are working to like when
 103 you have an open source and commercial versions of a software, for example.
 104 +
 105 If you want to start a disconnected history that records set of paths
 106 totally different from the original branch, you may want to first clear
 107 the index and the working tree, by running "git rm -rf ." from the
 108 top-level of the working tree, before preparing your files (by copying
 109 from elsewhere, extracting a tarball, etc.) in the working tree.
 110
 111 -m::
 112 --merge::
 113         When switching branches,
 114         if you have local modifications to one or more files that
 115         are different between the current branch and the branch to
 116         which you are switching, the command refuses to switch
 117         branches in order to preserve your modifications in context.
 118         However, with this option, a three-way merge between the current
 119         branch, your working tree contents, and the new branch
 120         is done, and you will be on the new branch.
 121 +
 122 When a merge conflict happens, the index entries for conflicting
 123 paths are left unmerged, and you need to resolve the conflicts
 124 and mark the resolved paths with `git add` (or `git rm` if the merge
 125 should result in deletion of the path).
 126 +
 127 When checking out paths from the index, this option lets you recreate
 128 the conflicted merge in the specified paths.
 129
 130 --conflict=<style>::
 131         The same as --merge option above, but changes the way the
 132         conflicting hunks are presented, overriding the
 133         merge.conflictstyle configuration variable.  Possible values are
 134         "merge" (default) and "diff3" (in addition to what is shown by
 135         "merge" style, shows the original contents).
 136
 137 -p::
 138 --patch::
 139         Interactively select hunks in the difference between the
 140         <tree-ish> (or the index, if unspecified) and the working
 141         tree.  The chosen hunks are then applied in reverse to the
 142         working tree (and if a <tree-ish> was specified, the index).
 143 +
 144 This means that you can use `git checkout -p` to selectively discard
 145 edits from your current working tree.
 146
 147 <branch>::
 148         Branch to checkout; if it refers to a branch (i.e., a name that,
 149         when prepended with "refs/heads/", is a valid ref), then that
 150         branch is checked out. Otherwise, if it refers to a valid
 151         commit, your HEAD becomes "detached" and you are no longer on
 152         any branch (see below for details).
 153 +
 154 As a special case, the `"@\{-N\}"` syntax for the N-th last branch
 155 checks out the branch (instead of detaching).  You may also specify
 156 `-` which is synonymous with `"@\{-1\}"`.
 157 +
 158 As a further special case, you may use `"A...B"` as a shortcut for the
 159 merge base of `A` and `B` if there is exactly one merge base. You can
 160 leave out at most one of `A` and `B`, in which case it defaults to `HEAD`.
 161
 162 <new_branch>::
 163         Name for the new branch.
 164
 165 <start_point>::
 166         The name of a commit at which to start the new branch; see
 167         linkgit:git-branch[1] for details. Defaults to HEAD.
 168
 169 <tree-ish>::
 170         Tree to checkout from (when paths are given). If not specified,
 171         the index will be used.
 172
 173
 174
 175 Detached HEAD
 176 -------------
 177
 178 It is sometimes useful to be able to 'checkout' a commit that is
 179 not at the tip of one of your branches.  The most obvious
 180 example is to check out the commit at a tagged official release
 181 point, like this:
 182
 183 ------------
 184 $ git checkout v2.6.18
 185 ------------
 186
 187 Earlier versions of git did not allow this and asked you to
 188 create a temporary branch using the `-b` option, but starting from
 189 version 1.5.0, the above command 'detaches' your HEAD from the
 190 current branch and directly points at the commit named by the tag
 191 (`v2.6.18` in the example above).
 192
 193 You can use all git commands while in this state.  You can use
 194 `git reset --hard $othercommit` to further move around, for
 195 example.  You can make changes and create a new commit on top of
 196 a detached HEAD.  You can even create a merge by using `git
 197 merge $othercommit`.
 198
 199 The state you are in while your HEAD is detached is not recorded
 200 by any branch (which is natural --- you are not on any branch).
 201 What this means is that you can discard your temporary commits
 202 and merges by switching back to an existing branch (e.g. `git
 203 checkout master`), and a later `git prune` or `git gc` would
 204 garbage-collect them.  If you did this by mistake, you can ask
 205 the reflog for HEAD where you were, e.g.
 206
 207 ------------
 208 $ git log -g -2 HEAD
 209 ------------
 210
 211
 212 EXAMPLES
 213 --------
 214
 215 . The following sequence checks out the `master` branch, reverts
 216 the `Makefile` to two revisions back, deletes hello.c by
 217 mistake, and gets it back from the index.
 218 +
 219 ------------
 220 $ git checkout master             <1>
 221 $ git checkout master~2 Makefile  <2>
 222 $ rm -f hello.c
 223 $ git checkout hello.c            <3>
 224 ------------
 225 +
 226 <1> switch branch
 227 <2> take a file out of another commit
 228 <3> restore hello.c from the index
 229 +
 230 If you have an unfortunate branch that is named `hello.c`, this
 231 step would be confused as an instruction to switch to that branch.
 232 You should instead write:
 233 +
 234 ------------
 235 $ git checkout -- hello.c
 236 ------------
 237
 238 . After working in the wrong branch, switching to the correct
 239 branch would be done using:
 240 +
 241 ------------
 242 $ git checkout mytopic
 243 ------------
 244 +
 245 However, your "wrong" branch and correct "mytopic" branch may
 246 differ in files that you have modified locally, in which case
 247 the above checkout would fail like this:
 248 +
 249 ------------
 250 $ git checkout mytopic
 251 fatal: Entry 'frotz' not uptodate. Cannot merge.
 252 ------------
 253 +
 254 You can give the `-m` flag to the command, which would try a
 255 three-way merge:
 256 +
 257 ------------
 258 $ git checkout -m mytopic
 259 Auto-merging frotz
 260 ------------
 261 +
 262 After this three-way merge, the local modifications are _not_
 263 registered in your index file, so `git diff` would show you what
 264 changes you made since the tip of the new branch.
 265
 266 . When a merge conflict happens during switching branches with
 267 the `-m` option, you would see something like this:
 268 +
 269 ------------
 270 $ git checkout -m mytopic
 271 Auto-merging frotz
 272 ERROR: Merge conflict in frotz
 273 fatal: merge program failed
 274 ------------
 275 +
 276 At this point, `git diff` shows the changes cleanly merged as in
 277 the previous example, as well as the changes in the conflicted
 278 files.  Edit and resolve the conflict and mark it resolved with
 279 `git add` as usual:
 280 +
 281 ------------
 282 $ edit frotz
 283 $ git add frotz
 284 ------------
 285
 286
 287 Author
 288 ------
 289 Written by Linus Torvalds <torvalds@osdl.org>
 290
 291 Documentation
 292 --------------
 293 Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
 294
 295 GIT
 296 ---
 297 Part of the linkgit:git[1] suite