hgeditor

merge: let the user choose to merge, keep local or keep remote subrepo revisions

When a subrepo has changed on the local and remote revisions, prompt the user
whether it wants to merge those subrepo revisions, keep the local revision or
keep the remote revision.

Up until now mercurial would always perform a merge on a subrepo that had
changed on the local and the remote revisions. This is often inconvenient. For
example:

- You may want to perform the actual subrepo merge after you have merged the
parent subrepo files.
- Some subrepos may be considered "read only", in the sense that you are not
supposed to add new revisions to them. In those cases "merging a subrepo" means
choosing which _existing_ revision you want to use on the merged revision. This
is often the case for subrepos that contain binary dependencies (such as DLLs,
etc).

This new prompt makes mercurial better cope with those common scenarios.

Notes:

- The default behavior (which is the one that is used when ui is not
interactive) remains unchanged (i.e. merge is the default action).
- This prompt will be shown even if the ui --tool flag is set.
- I don't know of a way to test the "keep local" and "keep remote" options (i.e.
to force the test to choose those options).


# HG changeset patch
# User Angel Ezquerra <[e-mail]>
# Date 1378420708 -7200
#      Fri Sep 06 00:38:28 2013 +0200
# Node ID 2fb9cb0c7b26303ac3178b7739975e663075857d
# Parent  50d721553198cea51c30f53b76d41dc919280097
merge: let the user choose to merge, keep local or keep remote subrepo revisions

When a subrepo has changed on the local and remote revisions, prompt the user
whether it wants to merge those subrepo revisions, keep the local revision or
keep the remote revision.

Up until now mercurial would always perform a merge on a subrepo that had
changed on the local and the remote revisions. This is often inconvenient. For
example:

- You may want to perform the actual subrepo merge after you have merged the
parent subrepo files.
- Some subrepos may be considered "read only", in the sense that you are not
supposed to add new revisions to them. In those cases "merging a subrepo" means
choosing which _existing_ revision you want to use on the merged revision. This
is often the case for subrepos that contain binary dependencies (such as DLLs,
etc).

This new prompt makes mercurial better cope with those common scenarios.

Notes:

- The default behavior (which is the one that is used when ui is not
interactive) remains unchanged (i.e. merge is the default action).
- This prompt will be shown even if the ui --tool flag is set.
- I don't know of a way to test the "keep local" and "keep remote" options (i.e.
to force the test to choose those options).

#!/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 $?