Documentation / git-for-each-ref.txton commit git-for-each-ref.txt: minor improvements (c0f6dc9)
   1git-for-each-ref(1)
   2===================
   3
   4NAME
   5----
   6git-for-each-ref - Output information on each ref
   7
   8SYNOPSIS
   9--------
  10[verse]
  11'git-for-each-ref' [--count=<count>] [--shell|--perl|--python|--tcl]
  12                   [--sort=<key>]\* [--format=<format>] [<pattern>...]
  13
  14DESCRIPTION
  15-----------
  16
  17Iterate over all refs that match `<pattern>` and show them
  18according to the given `<format>`, after sorting them according
  19to the given set of `<key>`.  If `<max>` is given, stop after
  20showing that many refs.  The interpolated values in `<format>`
  21can optionally be quoted as string literals in the specified
  22host language allowing their direct evaluation in that language.
  23
  24OPTIONS
  25-------
  26<count>::
  27        By default the command shows all refs that match
  28        `<pattern>`.  This option makes it stop after showing
  29        that many refs.
  30
  31<key>::
  32        A field name to sort on.  Prefix `-` to sort in
  33        descending order of the value.  When unspecified,
  34        `refname` is used.  You may use the --sort=<key> option
  35        multiple times, in which case the last key becomes the primary
  36        key.
  37
  38<format>::
  39        A string that interpolates `%(fieldname)` from the
  40        object pointed at by a ref being shown.  If `fieldname`
  41        is prefixed with an asterisk (`*`) and the ref points
  42        at a tag object, the value for the field in the object
  43        tag refers is used.  When unspecified, defaults to
  44        `%(objectname) SPC %(objecttype) TAB %(refname)`.
  45        It also interpolates `%%` to `%`, and `%xx` where `xx`
  46        are hex digits interpolates to character with hex code
  47        `xx`; for example `%00` interpolates to `\0` (NUL),
  48        `%09` to `\t` (TAB) and `%0a` to `\n` (LF).
  49
  50<pattern>::
  51        If one or more patterns are given, only refs are shown that
  52        match againt at least one pattern, either using fnmatch(3) or
  53        literally, in the latter case matching completely or from the
  54        beginning up to a slash.
  55
  56--shell, --perl, --python, --tcl::
  57        If given, strings that substitute `%(fieldname)`
  58        placeholders are quoted as string literals suitable for
  59        the specified host language.  This is meant to produce
  60        a scriptlet that can directly be `eval`ed.
  61
  62
  63FIELD NAMES
  64-----------
  65
  66Various values from structured fields in referenced objects can
  67be used to interpolate into the resulting output, or as sort
  68keys.
  69
  70For all objects, the following names can be used:
  71
  72refname::
  73        The name of the ref (the part after $GIT_DIR/).
  74
  75objecttype::
  76        The type of the object (`blob`, `tree`, `commit`, `tag`).
  77
  78objectsize::
  79        The size of the object (the same as `git-cat-file -s` reports).
  80
  81objectname::
  82        The object name (aka SHA-1).
  83
  84In addition to the above, for commit and tag objects, the header
  85field names (`tree`, `parent`, `object`, `type`, and `tag`) can
  86be used to specify the value in the header field.
  87
  88Fields that have name-email-date tuple as its value (`author`,
  89`committer`, and `tagger`) can be suffixed with `name`, `email`,
  90and `date` to extract the named component.
  91
  92The first line of the message in a commit and tag object is
  93`subject`, the remaining lines are `body`.  The whole message
  94is `contents`.
  95
  96For sorting purposes, fields with numeric values sort in numeric
  97order (`objectsize`, `authordate`, `committerdate`, `taggerdate`).
  98All other fields are used to sort in their byte-value order.
  99
 100In any case, a field name that refers to a field inapplicable to
 101the object referred by the ref does not cause an error.  It
 102returns an empty string instead.
 103
 104As a special case for the date-type fields, you may specify a format for
 105the date by adding one of `:default`, `:relative`, `:short`, `:local`,
 106`:iso8601` or `:rfc2822` to the end of the fieldname; e.g.
 107`%(taggerdate:relative)`.
 108
 109
 110EXAMPLES
 111--------
 112
 113An example directly producing formatted text.  Show the most recent
 1143 tagged commits::
 115
 116------------
 117#!/bin/sh
 118
 119git-for-each-ref --count=3 --sort='-*authordate' \
 120--format='From: %(*authorname) %(*authoremail)
 121Subject: %(*subject)
 122Date: %(*authordate)
 123Ref: %(*refname)
 124
 125%(*body)
 126' 'refs/tags'
 127------------
 128
 129
 130A simple example showing the use of shell eval on the output,
 131demonstrating the use of --shell.  List the prefixes of all heads::
 132------------
 133#!/bin/sh
 134
 135git-for-each-ref --shell --format="ref=%(refname)" refs/heads | \
 136while read entry
 137do
 138        eval "$entry"
 139        echo `dirname $ref`
 140done
 141------------
 142
 143
 144A bit more elaborate report on tags, demonstrating that the format
 145may be an entire script::
 146------------
 147#!/bin/sh
 148
 149fmt='
 150        r=%(refname)
 151        t=%(*objecttype)
 152        T=${r#refs/tags/}
 153
 154        o=%(*objectname)
 155        n=%(*authorname)
 156        e=%(*authoremail)
 157        s=%(*subject)
 158        d=%(*authordate)
 159        b=%(*body)
 160
 161        kind=Tag
 162        if test "z$t" = z
 163        then
 164                # could be a lightweight tag
 165                t=%(objecttype)
 166                kind="Lightweight tag"
 167                o=%(objectname)
 168                n=%(authorname)
 169                e=%(authoremail)
 170                s=%(subject)
 171                d=%(authordate)
 172                b=%(body)
 173        fi
 174        echo "$kind $T points at a $t object $o"
 175        if test "z$t" = zcommit
 176        then
 177                echo "The commit was authored by $n $e
 178at $d, and titled
 179
 180    $s
 181
 182Its message reads as:
 183"
 184                echo "$b" | sed -e "s/^/    /"
 185                echo
 186        fi
 187'
 188
 189eval=`git-for-each-ref --shell --format="$fmt" \
 190        --sort='*objecttype' \
 191        --sort=-taggerdate \
 192        refs/tags`
 193eval "$eval"
 194------------