git-authors

#!/bin/sh

# Outputs a list of authors of commits, for the git repository where this is run.
# The output contains one name per line, in alphabetical order by first name.

# Command-line arguments:
#  --punctuation  Add commas after names (except a period after the last one)
# Formatting of accented characters:
#  --html         Use HTML escape sequences for accented characters
#  --latex        Use LaTeX escape sequences for accented characters
#  --texinfo      Use Texinfo escape sequences for accented characters

while :; do
    case $1 in
        --punctuation)
            punctuation=1
            ;;
        --html)
            html=1
            ;;
        --latex)
            latex=1
            ;;
        --texinfo)
            texinfo=1
            ;;
        --)              # End of all options.
            shift
            break
            ;;
        -?*)
            printf 'WARN: Unknown option (ignored): %s\n' "$1" >&2
            ;;
        *)               # Default case: No more options, so break out of the loop.
            break
    esac

    shift
done

# shellcheck disable=SC2091 # Result is "true" or "false", surround with $(...) to interpret it.
if $(git rev-parse --is-shallow-repository); then
  # It would be more efficient to use --filter=tree:0, but that is legal only if extensions.partialClone is set.
  git fetch --unshallow --quiet
fi
# shellcheck disable=SC2015 # sed won't fail.
git log | grep '^\(Author\|    Co-authored-by\):' | \
  sed -E 's/(Author|    Co-authored-by): (.*)/\2/' | sed -E 's/(.*) <.*>/\1/' | \
  LC_ALL=C sort -u | \
  sed -f "$(dirname "$0")"/git-authors.sed | LC_ALL=C sort -u | \
  ( [ -n "${html+x}" ] && sed -e "s/á/\\&aacute;/" -e "s/é/\\&eacute;/" -e "s/ß/\\&szlig;/" || cat ) | \
  ( [ -n "${latex+x}" ] && sed -e "s/á/\\\\'a/" -e "s/é/\\\\'e/" -e "s/ß/\\\\ss /" || cat ) | \
  ( [ -n "${texinfo+x}" ] && sed -e "s/á/@'a/" -e "s/é/@'e/" -e "s/ß/@ss /" || cat ) | \
  ( [ -n "${punctuation+x}" ] && sed -e 's/$/,/' -e '$ s/,$/./' || cat ) | \
  cat