view hgeditor @ 23238:39eb9f78f968

context.status: move manifest caching trick to _buildstatus()

In basectx._buildstatus(), we read the manifests for the two revisions
being compared. For "caching reasons" unknown to me, it is better to
read the earlier manifest first, which basectx._prestatus() takes care
of. However, if the 'self' context is a committablectx and the 'other'
context is the parent of the working directory (as in the very common
case of plain "hg status"), there is no need to read any manifests at
all -- all that's needed is the dirstate status. To avoid reading the
manifests, _prestatus() is overridden in committablectx and avoids
calling its super method, and _buildstatus() calls its super method
only if the 'other' context is not the parent of the working
directory.

It seems easier to follow what's happening if we move the pre-fetching
to _buildstatus() just before the place where the manifests are
fetched. We just need to add an extra check that the revision is not
None to handle the case that was previously handled by subclass
overriding. That also makes it safe for committablectx._prestatus() to
call its parent, although the latter now becomes empty, so we won't
bother.

#!/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 $?