hgeditor

extdiff: quote user-supplied options passed to shell

$ hg extdiff -p cmd -o "name <[e-mail]>"
resulted in a shell redirection error (due to the less-than sign),
rather than passing the single option to cmd. This was due to options
not being quoted for passing to the shell, via util.system(). Apply
util.shellquote() to each of the user-specified options (-o) to the
comparison program before they are concatenated and passed to
util.system(). The requested external diff command (-p) and the
files/directories being compared are already quoted correctly.

The discussion at the time of changeset be98c5ce4022 correctly noted
that this course of action breaks whitespace-separated options specified
for external diff commands in the configuration. The lower part of the
patch corrects this by lexing options read from the configuration file
into separate options rather than reading them all into the first
option.

Update test to cover these conditions.

Related changesets (reverse-chronological):
- be98c5ce4022 (fix reverted to make configuration file options work)
- 453097750fbf (issue fixed but without fix for configuration file)

#!/bin/sh
#
# This is an example of using HGEDITOR to create of diff to review the
# changes while commiting.

# If you want to pass your favourite editor some other parameters
# only for Mercurial, modify this:
case "${EDITOR}" in
    "")
        EDITOR="vi"
        ;;
    emacs)
        EDITOR="$EDITOR -nw"
        ;;
    gvim|vim)
        EDITOR="$EDITOR -f -o"
        ;;
esac


HGTMP=""
cleanup_exit() {
    rm -rf "$HGTMP"
}

# Remove temporary files even if we get interrupted
trap "cleanup_exit" 0 # normal exit
trap "exit 255" HUP INT QUIT ABRT TERM

HGTMP=$(mktemp -d ${TMPDIR-/tmp}/hgeditor.XXXXXX)
[ x$HGTMP != x -a -d $HGTMP ] || {
  echo "Could not create temporary directory! Exiting." 1>&2
  exit 1
}

(
    grep '^HG: changed' "$1" | cut -b 13- | while read changed; do
        "$HG" diff "$changed" >> "$HGTMP/diff"
    done
)

cat "$1" > "$HGTMP/msg"

MD5=$(which md5sum 2>/dev/null) || \
    MD5=$(which md5 2>/dev/null)
[ -x "${MD5}" ] && CHECKSUM=`${MD5} "$HGTMP/msg"`
if [ -s "$HGTMP/diff" ]; then
    $EDITOR "$HGTMP/msg" "$HGTMP/diff" || exit $?
else
    $EDITOR "$HGTMP/msg" || exit $?
fi
[ -x "${MD5}" ] && (echo "$CHECKSUM" | ${MD5} -c >/dev/null 2>&1 && exit 13)

mv "$HGTMP/msg" "$1"

exit $?