hgeditor

patch: include flag-only file changes in "special" when filtering (issue5864)

This patch fix the issue5864 (or maybe issue5865 too) which occurs during
split (or I should say at the time of filtering the hunks in interactive
mode) where user hits a not ending loop of "no changes to record".
And it's not only the case for split it will happen in every interactive
case for e.g. `hg commit -i` or `hg uncommit -i`

After looking into code I found that when filtering we have some
notation called "special" for the file headers which doesn't contain
any hunk and just contain the header (for e.g. newly added empty file
or deleted file) where the user cannot change the content of operation.

And I think we can put this "flag-only" file change in that same bucket
of "special". But I doubt a bit about the case when a file have flag change
and atleast one hunk then user won't be able to separate the flag change
from hunks.
Changed test file reflect the fixed behaviour.

Differential Revision: https://phab.mercurial-scm.org/D6058

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

# 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 $?