view hgeditor @ 18944:a9c443b3b240

unionrepo: read-only operations on a union of two localrepos

unionrepo is just like bundlerepo without bundles.

The implementation is very similar to bundlerepo, but I don't see any obvious
way to generalize it.

Some most obvious use cases for this would be log and diff across local repos,
as a kind of preview of pulls, for instance:

  $ hg -R union:repo1+repo2 heads
  $ hg -R union:repo1+repo2 log -r REPO1REV -r REPO2REV
  $ hg -R union:repo1+repo2 log -r '::REPO1REV-::REPO2REV'
  $ hg -R union:repo1+repo2 log -r 'ancestor(REPO1REV,REPO2REV)'
  $ hg -R union:repo1+repo2 diff -r REPO1REV -r REPO2REV

This is going to be used in RhodeCode, and Bitbucket already uses something
similar. Having a core implementation would be beneficial.

#!/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 $?