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diff --git a/Documentation/git-rev-parse.txt b/Documentation/git-rev-parse.txt new file mode 100644 index 0000000000..d068a65377 --- /dev/null +++ b/Documentation/git-rev-parse.txt @@ -0,0 +1,377 @@ +git-rev-parse(1) +================ + +NAME +---- +git-rev-parse - Pick out and massage parameters + + +SYNOPSIS +-------- +[verse] +'git rev-parse' [ --option ] <args>... + +DESCRIPTION +----------- + +Many Git porcelainish commands take mixture of flags +(i.e. parameters that begin with a dash '-') and parameters +meant for the underlying 'git rev-list' command they use internally +and flags and parameters for the other commands they use +downstream of 'git rev-list'. This command is used to +distinguish between them. + + +OPTIONS +------- + +Operation Modes +~~~~~~~~~~~~~~~ + +Each of these options must appear first on the command line. + +--parseopt:: + Use 'git rev-parse' in option parsing mode (see PARSEOPT section below). + +--sq-quote:: + Use 'git rev-parse' in shell quoting mode (see SQ-QUOTE + section below). In contrast to the `--sq` option below, this + mode does only quoting. Nothing else is done to command input. + +Options for --parseopt +~~~~~~~~~~~~~~~~~~~~~~ + +--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. + +Options for Filtering +~~~~~~~~~~~~~~~~~~~~~ + +--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. + +Options for Output +~~~~~~~~~~~~~~~~~~ + +--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)" +eval "set -- $(git rev-parse --sq --prefix "$prefix" "$@")" +---- + +--verify:: + Verify that exactly one parameter is provided, and that it + can be turned into a raw 20-byte SHA-1 that can be used to + access the object database. If so, emit it to the standard + output; otherwise, error out. ++ +If you want to make sure that the output actually names an object in +your object database and/or can be used as a specific type of object +you require, you can add "^{type}" peeling operator to the parameter. +For example, `git rev-parse "$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. + +-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. + +--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-{asterisk}'). In contrast to the `--sq-quote` option, + the command input is still interpreted as usual. + +--not:: + When showing object names, prefix them with '{caret}' and + strip '{caret}' 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. + +--short:: +--short=number:: + Instead of outputting the full SHA-1 values of object names try to + abbreviate them to a shorter unique name. When no length is specified + 7 is used. The minimum length is 4. + +--symbolic:: + Usually the object names are output in SHA-1 form (with + possible '{caret}' 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 show them as full + refnames (e.g. "refs/heads/master"). + +Options for Objects +~~~~~~~~~~~~~~~~~~~ + +--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 `/*`. + +--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. + +Options for Files +~~~~~~~~~~~~~~~~~ + +--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. + +--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. + +--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". + +--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. + +--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-toplevel:: + Show the absolute path of the top-level directory. + +Other Options +~~~~~~~~~~~~~ + +--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'. + +<args>...:: + Flags and parameters to be parsed. + + +include::revisions.txt[] + +PARSEOPT +-------- + +In `--parseopt` mode, 'git rev-parse' helps massaging options to bring to shell +scripts the same facilities C builtins have. It works as an option normalizer +(e.g. splits single switches aggregate values), a bit like `getopt(1)` does. + +It takes on the standard input the specification of the options to parse and +understand, and echoes on the standard output a string suitable for `sh(1)` `eval` +to replace the arguments with normalized ones. In case of error, it outputs +usage on the standard error stream, and exits with code 129. + +Note: Make sure you quote the result when passing it to `eval`. See +below for an example. + +Input Format +~~~~~~~~~~~~ + +'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 more than one) are used for the usage. +The lines after the separator describe the options. + +Each line of options has this format: + +------------ +<opt_spec><flags>* 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. `h,help`, `dry-run` and `f` are all three correct + `<opt_spec>`. + +`<flags>`:: + `<flags>` are of `*`, `=`, `?` or `!`. + * Use `=` if the option takes an argument. + + * Use `?` to mean that the option is optional (though its use is discouraged). + + * 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 linkgit:gitcli[7]. + + * Use `!` to not make the corresponding negated long option available. + +The remainder of the line, after stripping the spaces, is used +as the help associated to 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). + +Example +~~~~~~~ + +------------ +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 + + An option group Header +C? option C with an optional argument" + +eval "$(echo "$OPTS_SPEC" | git rev-parse --parseopt -- "$@" || echo exit $?)" +------------ + +SQ-QUOTE +-------- + +In `--sq-quote` mode, 'git rev-parse' echoes on the standard output a +single line suitable for `sh(1)` `eval`. This line is made by +normalizing the arguments following `--sq-quote`. Nothing other than +quoting the arguments is done. + +If you want command input to still be interpreted as usual by +'git rev-parse' before the output is shell quoted, see the `--sq` +option. + +Example +~~~~~~~ + +------------ +$ 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 b'c" +------------ + +EXAMPLES +-------- + +* Print the object name of the current commit: ++ +------------ +$ git rev-parse --verify HEAD +------------ + +* Print the commit object name from the revision in the $REV shell variable: ++ +------------ +$ git rev-parse --verify $REV^{commit} +------------ ++ +This will error out if $REV is empty or not a valid revision. + +* Similar to above: ++ +------------ +$ git rev-parse --default master --verify $REV +------------ ++ +but if $REV is empty, the commit object name from master will be printed. + +GIT +--- +Part of the linkgit:git[1] suite |