hgeditor

setup: unconditionally enable the `long-paths-support` option on Windows

I don't see anything talking about why this was experimental in the first place,
but maybe it was concern about the level of python2 support for it.  But now,
both `python.exe` and the PyOxidizer build of `hg.exe` have a manifest that
enables it, so leaving it off would mean some Mercurial installations could
operate on a repo with long paths, and others couldn't.  Note that only the wide
character functions (XxxW) will have the length restriction lifted.

Sadly, distutils applies `/MANIFEST:EMBED` to the linker in a way that can't
easily be turned off, so we can't use `/MANIFESTFILE` with `extra_preargs` on
`link_executable`.  Fortunately, the compiler object provides a path to the
`mt.exe` it found during initialization, because the previous incarnation seems
to have assumed it is being run within an activated Visual Studio environment.
That causes MSYS builds to fail, and probably would have broke the CI
environment.

#!/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 $?