Manpages - git-rev-parse.1

Each of these options must appear first on the command line.

–parseopt

Use git rev-parse in option parsing mode (see PARSEOPT section below). The command in this mode can be used outside a repository or a working tree controlled by a repository.

–sq-quote

Use git rev-parse in shell quoting mode (see SQ-QUOTE section below). In contrast to the –sq option below, this mode only does quoting. Nothing else is done to command input. The command in this mode can be used outside a repository or a working tree controlled by a repository.

–keep-dashdash

Only meaningful in –parseopt mode. Tells the option parser to echo out the first – met instead of skipping it.

–stop-at-non-option

Only meaningful in –parseopt mode. Lets the option parser stop at the first non-option argument. This can be used to parse sub-commands that take options themselves.

–stuck-long

Only meaningful in –parseopt mode. Output the options in their long form if available, and with their arguments stuck.

–revs-only

Do not output flags and parameters not meant for git rev-list command.

–no-revs

Do not output flags and parameters meant for git rev-list command.

–flags

Do not output non-flag parameters.

–no-flags

Do not output flag parameters.

–default <arg>

If there is no parameter given by the user, use <arg> instead.

–prefix <arg>

Behave as if git rev-parse was invoked from the <arg> subdirectory of the working tree. Any relative filenames are resolved as if they are prefixed by <arg> and will be printed in that form.

This can be used to convert arguments to a command run in a subdirectory so that they can still be used after moving to the top-level of the repository. For example:

prefix=$(git rev-parse --show-prefix)
cd "$(git rev-parse --show-toplevel)"
# rev-parse provides the -- needed for set
eval "set $(git rev-parse --sq --prefix "$prefix" -- "$@")"

–verify

Verify that exactly one parameter is provided, and that it can be turned into a raw 20-byte SHA-1 that can be used to access the object database. If so, emit it to the standard output; otherwise, error out.

If you want to make sure that the output actually names an object in your object database and/or can be used as a specific type of object you require, you can add the ^type peeling operator to the parameter. For example, git rev-parse "$VAR^commit" will make sure $VAR names an existing object that is a commit-ish (i.e. a commit, or an annotated tag that points at a commit). To make sure that $VAR names an existing object of any type, git rev-parse "$VAR^object" can be used.

Note that if you are verifying a name from an untrusted source, it is wise to use –end-of-options so that the name argument is not mistaken for another option.

-q, –quiet

Only meaningful in –verify mode. Do not output an error message if the first argument is not a valid object name; instead exit with non-zero status silently. SHA-1s for valid object names are printed to stdout on success.

–sq

Usually the output is made one line per flag and parameter. This option makes output a single line, properly quoted for consumption by shell. Useful when you expect your parameter to contain whitespaces and newlines (e.g. when using pickaxe -S with git diff-*). In contrast to the –sq-quote option, the command input is still interpreted as usual.

–short[=<length>]

Same as –verify but shortens the object name to a unique prefix with at least length characters. The minimum length is 4, the default is the effective value of the core.abbrev configuration variable (see *git-config*(1)).

–not

When showing object names, prefix them with ^ and strip ^ prefix from the object names that already have one.

–abbrev-ref[=(strict|loose)]

A non-ambiguous short name of the objects name. The option core.warnAmbiguousRefs is used to select the strict abbreviation mode.

–symbolic

Usually the object names are output in SHA-1 form (with possible ^ prefix); this option makes them output in a form as close to the original input as possible.

–symbolic-full-name

This is similar to –symbolic, but it omits input that are not refs (i.e. branch or tag names; or more explicitly disambiguating "heads/master" form, when you want to name the "master" branch when there is an unfortunately named tag "master"), and shows them as full refnames (e.g. "refs/heads/master").

–output-object-format=(sha1|sha256|storage)

Allow oids to be input from any object format that the current repository supports.

Specifying "sha1" translates if necessary and returns a sha1 oid.

Specifying "sha256" translates if necessary and returns a sha256 oid.

Specifying "storage" translates if necessary and returns an oid in
encoded in the storage hash algorithm.

–all

Show all refs found in refs/.

–branches[=<pattern>], –tags[=<pattern>], –remotes[=<pattern>]

Show all branches, tags, or remote-tracking branches, respectively (i.e., refs found in refs/heads, refs/tags, or refs/remotes, respectively).

If a pattern is given, only refs matching the given shell glob are shown. If the pattern does not contain a globbing character (?, *, or [), it is turned into a prefix match by appending /*.

–glob=<pattern>

Show all refs matching the shell glob pattern pattern. If the pattern does not start with refs/, this is automatically prepended. If the pattern does not contain a globbing character (?, *, or [), it is turned into a prefix match by appending /*.

–exclude=<glob-pattern>

Do not include refs matching <glob-pattern> that the next –all, –branches, –tags, –remotes, or –glob would otherwise consider. Repetitions of this option accumulate exclusion patterns up to the next –all, –branches, –tags, –remotes, or –glob option (other options or arguments do not clear accumulated patterns).

The patterns given should not begin with refs/heads, refs/tags, or refs/remotes when applied to –branches, –tags, or –remotes, respectively, and they must begin with refs/ when applied to –glob or –all. If a trailing /* is intended, it must be given explicitly.

–exclude-hidden=(fetch|receive|uploadpack)

Do not include refs that would be hidden by git-fetch, git-receive-pack or git-upload-pack by consulting the appropriate fetch.hideRefs, receive.hideRefs or uploadpack.hideRefs configuration along with transfer.hideRefs (see git-config*(1)). This option affects the next pseudo-ref option *–all or –glob and is cleared after processing them.

–disambiguate=<prefix>

Show every object whose name begins with the given prefix. The <prefix> must be at least 4 hexadecimal digits long to avoid listing each and every object in the repository by mistake.

–local-env-vars

List the GIT_* environment variables that are local to the repository (e.g. GIT_DIR or GIT_WORK_TREE, but not GIT_EDITOR). Only the names of the variables are listed, not their value, even if they are set.

–path-format=(absolute|relative)

Controls the behavior of certain other options. If specified as absolute, the paths printed by those options will be absolute and canonical. If specified as relative, the paths will be relative to the current working directory if that is possible. The default is option specific.

This option may be specified multiple times and affects only the arguments that follow it on the command line, either to the end of the command line or the next instance of this option.

The following options are modified by –path-format:

–git-dir

Show $GIT_DIR if defined. Otherwise show the path to the .git directory. The path shown, when relative, is relative to the current working directory.

If $GIT_DIR is not defined and the current directory is not detected to lie in a Git repository or work tree print a message to stderr and exit with nonzero status.

–git-common-dir

Show $GIT_COMMON_DIR if defined, else $GIT_DIR.

–resolve-git-dir <path>

Check if <path> is a valid repository or a gitfile that points at a valid repository, and print the location of the repository. If <path> is a gitfile then the resolved path to the real repository is printed.

–git-path <path>

Resolve "$GIT_DIR/<path>" and takes other path relocation variables such as $GIT_OBJECT_DIRECTORY, $GIT_INDEX_FILE... into account. For example, if $GIT_OBJECT_DIRECTORY is set to /foo/bar then "git rev-parse –git-path objects/abc" returns /foo/bar/abc.

–show-toplevel

Show the (by default, absolute) path of the top-level directory of the working tree. If there is no working tree, report an error.

–show-superproject-working-tree

Show the absolute path of the root of the superproject's working tree (if exists) that uses the current repository as its submodule. Outputs nothing if the current repository is not used as a submodule by any project.

–shared-index-path

Show the path to the shared index file in split index mode, or empty if not in split-index mode.

The following options are unaffected by –path-format:

–absolute-git-dir

Like –git-dir, but its output is always the canonicalized absolute path.

–is-inside-git-dir

When the current working directory is below the repository directory print "true", otherwise "false".

–is-inside-work-tree

When the current working directory is inside the work tree of the repository print "true", otherwise "false".

–is-bare-repository

When the repository is bare print "true", otherwise "false".

–is-shallow-repository

When the repository is shallow print "true", otherwise "false".

–show-cdup

When the command is invoked from a subdirectory, show the path of the top-level directory relative to the current directory (typically a sequence of "../", or an empty string).

–show-prefix

When the command is invoked from a subdirectory, show the path of the current directory relative to the top-level directory.

–show-object-format[=(storage|input|output)]

Show the object format (hash algorithm) used for the repository for storage inside the .git directory, input, or output. For input, multiple algorithms may be printed, space-separated. If not specified, the default is "storage".

–show-ref-format

Show the reference storage format used for the repository.

–since=<datestring>, –after=<datestring>

Parse the date string, and output the corresponding –max-age= parameter for git rev-list.

–until=<datestring>, –before=<datestring>

Parse the date string, and output the corresponding –min-age= parameter for git rev-list.

<arg>…

Flags and parameters to be parsed.

^<rev> (caret) Notation

To exclude commits reachable from a commit, a prefix ^ notation is used. E.g. ^r1 r2 means commits reachable from r2 but exclude the ones reachable from r1 (i.e. r1 and its ancestors).

The .. (two-dot) Range Notation

The ^r1 r2 set operation appears so often that there is a shorthand for it. When you have two commits r1 and r2 (named according to the syntax explained in SPECIFYING REVISIONS above), you can ask for commits that are reachable from r2 excluding those that are reachable from r1 by ^r1 r2 and it can be written as r1..r2.

The … (three-dot) Symmetric Difference Notation

A similar notation r1…r2 is called symmetric difference of r1 and r2 and is defined as r1 r2 –not $(git merge-base –all r1 r2). It is the set of commits that are reachable from either one of r1 (left side) or r2 (right side) but not from both.

In these two shorthand notations, you can omit one end and let it default to HEAD. For example, origin.. is a shorthand for origin..HEAD and asks "What did I do since I forked from the origin branch?" Similarly, ..origin is a shorthand for HEAD..origin and asks "What did the origin do since I forked from them?" Note that .. would mean HEAD..HEAD which is an empty range that is both reachable and unreachable from HEAD.

Commands that are specifically designed to take two distinct ranges (e.g. "git range-diff R1 R2" to compare two ranges) do exist, but they are exceptions. Unless otherwise noted, all "git" commands that operate on a set of commits work on a single revision range. In other words, writing two "two-dot range notation" next to each other, e.g.

$ git log A..B C..D

does not specify two revision ranges for most commands. Instead it will name a single connected set of commits, i.e. those that are reachable from either B or D but are reachable from neither A or C. In a linear history like this:

---A---B---o---o---C---D

because A and B are reachable from C, the revision range specified by these two dotted ranges is a single commit D.

Three other shorthands exist, particularly useful for merge commits, for naming a set that is formed by a commit and its parent commits.

The r1^@ notation means all parents of r1.

The r1^! notation includes commit r1 but excludes all of its parents. By itself, this notation denotes the single commit r1.

The <rev>^-[<n>] notation includes <rev> but excludes the <n>th parent (i.e. a shorthand for <rev>^<n>..<rev>), with <n> = 1 if not given. This is typically useful for merge commits where you can just pass <commit>^- to get all the commits in the branch that was merged in merge commit <commit> (including <commit> itself).

While <rev>^<n> was about specifying a single commit parent, these three notations also consider its parents. For example you can say HEAD^2^@, however you cannot say HEAD^@^2.

git rev-parse –parseopt input format is fully text based. It has two parts, separated by a line that contains only –. The lines before the separator (should be one or more) are used for the usage. The lines after the separator describe the options.

Each line of options has this format:

<opt-spec><flags>*<arg-hint>? SP+ help LF

<opt-spec>

its format is the short option character, then the long option name separated by a comma. Both parts are not required, though at least one is necessary. May not contain any of the <flags> characters. h,help, dry-run and f are examples of correct <opt-spec>.

<flags>

<flags> are of *, =, ? or !.

·

Use = if the option takes an argument.

·

Use ? to mean that the option takes an optional argument. You probably want to use the –stuck-long mode to be able to unambiguously parse the optional argument.

·

Use * to mean that this option should not be listed in the usage generated for the -h argument. It's shown for –help-all as documented in *gitcli*(7).

·

Use ! to not make the corresponding negated long option available.

<arg-hint>

<arg-hint>, if specified, is used as a name of the argument in the help output, for options that take arguments. <arg-hint> is terminated by the first whitespace. It is customary to use a dash to separate words in a multi-word argument hint.

The remainder of the line, after stripping the spaces, is used as the help associated with the option.

Blank lines are ignored, and lines that don't match this specification are used as option group headers (start the line with a space to create such lines on purpose).

OPTS_SPEC="\
some-command [<options>] <args>...

some-command does foo and bar!
--
h,help!   show the help

foo       some nifty option --foo
bar=      some cool option --bar with an argument
baz=arg   another cool option --baz with a named argument
qux?path  qux may take a path argument but has meaning by itself

  An option group Header
C?        option C with an optional argument"

eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)"

When "$@" is -h or –help in the above example, the following usage text would be shown:

usage: some-command [<options>] <args>...

    some-command does foo and bar!

    -h, --help            show the help
    --[no-]foo            some nifty option --foo
    --[no-]bar ...        some cool option --bar with an argument
    --[no-]baz <arg>      another cool option --baz with a named argument
    --[no-]qux[=<path>]   qux may take a path argument but has meaning by itself

An option group Header
    -C[...]               option C with an optional argument

$ cat >your-git-script.sh <<\EOF
#!/bin/sh
args=$(git rev-parse --sq-quote "$@")   # quote user-supplied arguments
command="git frotz -n24 $args"          # and use it inside a handcrafted
                                        # command line
eval "$command"
EOF

$ sh your-git-script.sh "a bc"