hgeditor

Fixes and cleanups to hgeditor:
- "HG: merge resolve" isn't supported for a long time now.
- detection of unchanged commit message if signing is turned off.
- don't add manifest hash to commit message if not signing.

#!/bin/sh
#
# This is an example of using HGEDITOR to automate the signing of
# commits and so on.

# change this to one to turn on GPG support
SIGN=0

T1=""; T2=""
cleanup_exit() {
    rm -f "$T1" "$T2"
    exit $1
}

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

# Remove temporary files even if we get interrupted
trap "cleanup_exit 255" TERM KILL INT QUIT ABRT
T1=`mktemp`; T2=`mktemp`
(
    cd "`hg root`"
    grep '^HG: changed' "$1" | cut -b 13- | while read changed; do
        hg diff "$changed" >> "$T2"
    done
)

echo > "$T1"
if [ "$SIGN" == "1" ]; then
    MANIFEST=`grep '^HG: manifest hash' "$1" | cut -b 19-`
    echo -e "\nmanifest hash: $MANIFEST" >> "$T1"
fi
grep -vE '^(HG: manifest hash .*)?$' "$1" >> "$T1"

CHECKSUM=`md5sum "$T1"`
$EDITOR "$T1" "$T2" || cleanup_exit $?
echo "$CHECKSUM" | md5sum -c 2>/dev/null && cleanup_exit 13

if [ "$SIGN" == "1" ]; then
    {
        head -n 1 "$T1"
        echo
        grep -v "^HG:" "$T1" | gpg -t -a -u "${HGUSER}" --clearsign
    } > "$T2" && mv "$T2" "$1"
else
    mv "$T1" "$1"
fi

cleanup_exit $?