Documentation / git-tag.txton commit merge: allow fast-forward when merging a tracked tag (adcc94a)
   1git-tag(1)
   2==========
   3
   4NAME
   5----
   6git-tag - Create, list, delete or verify a tag object signed with GPG
   7
   8
   9SYNOPSIS
  10--------
  11[verse]
  12'git tag' [-a | -s | -u <keyid>] [-f] [-m <msg> | -F <file>]
  13        <tagname> [<commit> | <object>]
  14'git tag' -d <tagname>...
  15'git tag' [-n[<num>]] -l [--contains <commit>] [--no-contains <commit>]
  16        [--points-at <object>] [--column[=<options>] | --no-column]
  17        [--create-reflog] [--sort=<key>] [--format=<format>]
  18        [--[no-]merged [<commit>]] [<pattern>...]
  19'git tag' -v [--format=<format>] <tagname>...
  20
  21DESCRIPTION
  22-----------
  23
  24Add a tag reference in `refs/tags/`, unless `-d/-l/-v` is given
  25to delete, list or verify tags.
  26
  27Unless `-f` is given, the named tag must not yet exist.
  28
  29If one of `-a`, `-s`, or `-u <keyid>` is passed, the command
  30creates a 'tag' object, and requires a tag message.  Unless
  31`-m <msg>` or `-F <file>` is given, an editor is started for the user to type
  32in the tag message.
  33
  34If `-m <msg>` or `-F <file>` is given and `-a`, `-s`, and `-u <keyid>`
  35are absent, `-a` is implied.
  36
  37Otherwise just a tag reference for the SHA-1 object name of the commit object is
  38created (i.e. a lightweight tag).
  39
  40A GnuPG signed tag object will be created when `-s` or `-u
  41<keyid>` is used.  When `-u <keyid>` is not used, the
  42committer identity for the current user is used to find the
  43GnuPG key for signing.  The configuration variable `gpg.program`
  44is used to specify custom GnuPG binary.
  45
  46Tag objects (created with `-a`, `-s`, or `-u`) are called "annotated"
  47tags; they contain a creation date, the tagger name and e-mail, a
  48tagging message, and an optional GnuPG signature. Whereas a
  49"lightweight" tag is simply a name for an object (usually a commit
  50object).
  51
  52Annotated tags are meant for release while lightweight tags are meant
  53for private or temporary object labels. For this reason, some git
  54commands for naming objects (like `git describe`) will ignore
  55lightweight tags by default.
  56
  57
  58OPTIONS
  59-------
  60-a::
  61--annotate::
  62        Make an unsigned, annotated tag object
  63
  64-s::
  65--sign::
  66        Make a GPG-signed tag, using the default e-mail address's key.
  67
  68-u <keyid>::
  69--local-user=<keyid>::
  70        Make a GPG-signed tag, using the given key.
  71
  72-f::
  73--force::
  74        Replace an existing tag with the given name (instead of failing)
  75
  76-d::
  77--delete::
  78        Delete existing tags with the given names.
  79
  80-v::
  81--verify::
  82        Verify the GPG signature of the given tag names.
  83
  84-n<num>::
  85        <num> specifies how many lines from the annotation, if any,
  86        are printed when using -l. Implies `--list`.
  87+
  88The default is not to print any annotation lines.
  89If no number is given to `-n`, only the first line is printed.
  90If the tag is not annotated, the commit message is displayed instead.
  91
  92-l::
  93--list::
  94        List tags. With optional `<pattern>...`, e.g. `git tag --list
  95        'v-*'`, list only the tags that match the pattern(s).
  96+
  97Running "git tag" without arguments also lists all tags. The pattern
  98is a shell wildcard (i.e., matched using fnmatch(3)). Multiple
  99patterns may be given; if any of them matches, the tag is shown.
 100+
 101This option is implicitly supplied if any other list-like option such
 102as `--contains` is provided. See the documentation for each of those
 103options for details.
 104
 105--sort=<key>::
 106        Sort based on the key given.  Prefix `-` to sort in
 107        descending order of the value. You may use the --sort=<key> option
 108        multiple times, in which case the last key becomes the primary
 109        key. Also supports "version:refname" or "v:refname" (tag
 110        names are treated as versions). The "version:refname" sort
 111        order can also be affected by the "versionsort.suffix"
 112        configuration variable.
 113        The keys supported are the same as those in `git for-each-ref`.
 114        Sort order defaults to the value configured for the `tag.sort`
 115        variable if it exists, or lexicographic order otherwise. See
 116        linkgit:git-config[1].
 117
 118--color[=<when>]:
 119        Respect any colors specified in the `--format` option. The
 120        `<when>` field must be one of `always`, `never`, or `auto` (if
 121        `<when>` is absent, behave as if `always` was given).
 122
 123-i::
 124--ignore-case::
 125        Sorting and filtering tags are case insensitive.
 126
 127--column[=<options>]::
 128--no-column::
 129        Display tag listing in columns. See configuration variable
 130        column.tag for option syntax.`--column` and `--no-column`
 131        without options are equivalent to 'always' and 'never' respectively.
 132+
 133This option is only applicable when listing tags without annotation lines.
 134
 135--contains [<commit>]::
 136        Only list tags which contain the specified commit (HEAD if not
 137        specified). Implies `--list`.
 138
 139--no-contains [<commit>]::
 140        Only list tags which don't contain the specified commit (HEAD if
 141        not specified). Implies `--list`.
 142
 143--merged [<commit>]::
 144        Only list tags whose commits are reachable from the specified
 145        commit (`HEAD` if not specified), incompatible with `--no-merged`.
 146
 147--no-merged [<commit>]::
 148        Only list tags whose commits are not reachable from the specified
 149        commit (`HEAD` if not specified), incompatible with `--merged`.
 150
 151--points-at <object>::
 152        Only list tags of the given object (HEAD if not
 153        specified). Implies `--list`.
 154
 155-m <msg>::
 156--message=<msg>::
 157        Use the given tag message (instead of prompting).
 158        If multiple `-m` options are given, their values are
 159        concatenated as separate paragraphs.
 160        Implies `-a` if none of `-a`, `-s`, or `-u <keyid>`
 161        is given.
 162
 163-F <file>::
 164--file=<file>::
 165        Take the tag message from the given file.  Use '-' to
 166        read the message from the standard input.
 167        Implies `-a` if none of `-a`, `-s`, or `-u <keyid>`
 168        is given.
 169
 170--cleanup=<mode>::
 171        This option sets how the tag message is cleaned up.
 172        The  '<mode>' can be one of 'verbatim', 'whitespace' and 'strip'.  The
 173        'strip' mode is default. The 'verbatim' mode does not change message at
 174        all, 'whitespace' removes just leading/trailing whitespace lines and
 175        'strip' removes both whitespace and commentary.
 176
 177--create-reflog::
 178        Create a reflog for the tag. To globally enable reflogs for tags, see
 179        `core.logAllRefUpdates` in linkgit:git-config[1].
 180        The negated form `--no-create-reflog` only overrides an earlier
 181        `--create-reflog`, but currently does not negate the setting of
 182        `core.logAllRefUpdates`.
 183
 184<tagname>::
 185        The name of the tag to create, delete, or describe.
 186        The new tag name must pass all checks defined by
 187        linkgit:git-check-ref-format[1].  Some of these checks
 188        may restrict the characters allowed in a tag name.
 189
 190<commit>::
 191<object>::
 192        The object that the new tag will refer to, usually a commit.
 193        Defaults to HEAD.
 194
 195<format>::
 196        A string that interpolates `%(fieldname)` from a tag ref being shown
 197        and the object it points at.  The format is the same as
 198        that of linkgit:git-for-each-ref[1].  When unspecified,
 199        defaults to `%(refname:strip=2)`.
 200
 201CONFIGURATION
 202-------------
 203By default, 'git tag' in sign-with-default mode (-s) will use your
 204committer identity (of the form `Your Name <your@email.address>`) to
 205find a key.  If you want to use a different default key, you can specify
 206it in the repository configuration as follows:
 207
 208-------------------------------------
 209[user]
 210    signingKey = <gpg-keyid>
 211-------------------------------------
 212
 213`pager.tag` is only respected when listing tags, i.e., when `-l` is
 214used or implied. The default is to use a pager.
 215See linkgit:git-config[1].
 216
 217DISCUSSION
 218----------
 219
 220On Re-tagging
 221~~~~~~~~~~~~~
 222
 223What should you do when you tag a wrong commit and you would
 224want to re-tag?
 225
 226If you never pushed anything out, just re-tag it. Use "-f" to
 227replace the old one. And you're done.
 228
 229But if you have pushed things out (or others could just read
 230your repository directly), then others will have already seen
 231the old tag. In that case you can do one of two things:
 232
 233. The sane thing.
 234Just admit you screwed up, and use a different name. Others have
 235already seen one tag-name, and if you keep the same name, you
 236may be in the situation that two people both have "version X",
 237but they actually have 'different' "X"'s.  So just call it "X.1"
 238and be done with it.
 239
 240. The insane thing.
 241You really want to call the new version "X" too, 'even though'
 242others have already seen the old one. So just use 'git tag -f'
 243again, as if you hadn't already published the old one.
 244
 245However, Git does *not* (and it should not) change tags behind
 246users back. So if somebody already got the old tag, doing a
 247'git pull' on your tree shouldn't just make them overwrite the old
 248one.
 249
 250If somebody got a release tag from you, you cannot just change
 251the tag for them by updating your own one. This is a big
 252security issue, in that people MUST be able to trust their
 253tag-names.  If you really want to do the insane thing, you need
 254to just fess up to it, and tell people that you messed up. You
 255can do that by making a very public announcement saying:
 256
 257------------
 258Ok, I messed up, and I pushed out an earlier version tagged as X. I
 259then fixed something, and retagged the *fixed* tree as X again.
 260
 261If you got the wrong tag, and want the new one, please delete
 262the old one and fetch the new one by doing:
 263
 264        git tag -d X
 265        git fetch origin tag X
 266
 267to get my updated tag.
 268
 269You can test which tag you have by doing
 270
 271        git rev-parse X
 272
 273which should return 0123456789abcdef.. if you have the new version.
 274
 275Sorry for the inconvenience.
 276------------
 277
 278Does this seem a bit complicated?  It *should* be. There is no
 279way that it would be correct to just "fix" it automatically.
 280People need to know that their tags might have been changed.
 281
 282
 283On Automatic following
 284~~~~~~~~~~~~~~~~~~~~~~
 285
 286If you are following somebody else's tree, you are most likely
 287using remote-tracking branches (eg. `refs/remotes/origin/master`).
 288You usually want the tags from the other end.
 289
 290On the other hand, if you are fetching because you would want a
 291one-shot merge from somebody else, you typically do not want to
 292get tags from there.  This happens more often for people near
 293the toplevel but not limited to them.  Mere mortals when pulling
 294from each other do not necessarily want to automatically get
 295private anchor point tags from the other person.
 296
 297Often, "please pull" messages on the mailing list just provide
 298two pieces of information: a repo URL and a branch name; this
 299is designed to be easily cut&pasted at the end of a 'git fetch'
 300command line:
 301
 302------------
 303Linus, please pull from
 304
 305        git://git..../proj.git master
 306
 307to get the following updates...
 308------------
 309
 310becomes:
 311
 312------------
 313$ git pull git://git..../proj.git master
 314------------
 315
 316In such a case, you do not want to automatically follow the other
 317person's tags.
 318
 319One important aspect of Git is its distributed nature, which
 320largely means there is no inherent "upstream" or
 321"downstream" in the system.  On the face of it, the above
 322example might seem to indicate that the tag namespace is owned
 323by the upper echelon of people and that tags only flow downwards, but
 324that is not the case.  It only shows that the usage pattern
 325determines who are interested in whose tags.
 326
 327A one-shot pull is a sign that a commit history is now crossing
 328the boundary between one circle of people (e.g. "people who are
 329primarily interested in the networking part of the kernel") who may
 330have their own set of tags (e.g. "this is the third release
 331candidate from the networking group to be proposed for general
 332consumption with 2.6.21 release") to another circle of people
 333(e.g. "people who integrate various subsystem improvements").
 334The latter are usually not interested in the detailed tags used
 335internally in the former group (that is what "internal" means).
 336That is why it is desirable not to follow tags automatically in
 337this case.
 338
 339It may well be that among networking people, they may want to
 340exchange the tags internal to their group, but in that workflow
 341they are most likely tracking each other's progress by
 342having remote-tracking branches.  Again, the heuristic to automatically
 343follow such tags is a good thing.
 344
 345
 346On Backdating Tags
 347~~~~~~~~~~~~~~~~~~
 348
 349If you have imported some changes from another VCS and would like
 350to add tags for major releases of your work, it is useful to be able
 351to specify the date to embed inside of the tag object; such data in
 352the tag object affects, for example, the ordering of tags in the
 353gitweb interface.
 354
 355To set the date used in future tag objects, set the environment
 356variable GIT_COMMITTER_DATE (see the later discussion of possible
 357values; the most common form is "YYYY-MM-DD HH:MM").
 358
 359For example:
 360
 361------------
 362$ GIT_COMMITTER_DATE="2006-10-02 10:31" git tag -s v1.0.1
 363------------
 364
 365include::date-formats.txt[]
 366
 367SEE ALSO
 368--------
 369linkgit:git-check-ref-format[1].
 370linkgit:git-config[1].
 371
 372GIT
 373---
 374Part of the linkgit:git[1] suite