contrib/editmerge

transaction: pass the name of the "undo" journal to the transaction

It is time for the transaction to be responsible for setting up the
undo data. It is necessary to move this logic into the transaction
because many more files are handled now, and the transaction is the
object tracking them all.

The value can be set to None if no undo should be set.

#!/usr/bin/env bash
# A simple script for opening merge conflicts in the editor.
# Use the following Mercurial settings to enable it.
#
# [ui]
# merge = editmerge
#
# [merge-tools]
# editmerge.args=$output
# editmerge.check=changed
# editmerge.premerge=keep

FILE=$1

getlines() {
  grep -n "<<<<<<" $FILE | cut -f1 -d:
}

# editor preference loosely based on http://mercurial.selenic.com/wiki/editor
# hg showconfig is at the bottom though, since it's slow to run (0.15 seconds)
ED=$HGEDITOR
if [ "$ED" = "" ] ; then
  ED=$VISUAL
fi
if [ "$ED" = "" ] ; then
  ED=$EDITOR
fi
if [ "$ED" = "" ] ; then
  ED=$(hg showconfig ui.editor)
fi
if [ "$ED" = "" ] ; then
  echo "merge failed - unable to find editor"
  exit 1
fi

if [ "$ED" = "emacs" ] || [ "$ED" = "nano" ] || [ "$ED" = "vim" ] ; then
  FIRSTLINE=$(getlines | head -n 1)
  PREVIOUSLINE=""

  # open the editor to the first conflict until there are no more
  # or the user stops editing the file
  while [ ! "$FIRSTLINE" = "" ] && [ ! "$FIRSTLINE" = "$PREVIOUSLINE" ] ; do
    $ED +$FIRSTLINE $FILE
    PREVIOUSLINE=$FIRSTLINE
    FIRSTLINE=$(getlines | head -n 1)
  done
else
  $ED $FILE
fi

# get the line numbers of the remaining conflicts
CONFLICTS=$(getlines | sed ':a;N;$!ba;s/\n/, /g')
if [ ! "$CONFLICTS" = "" ] ; then
  echo "merge failed - resolve the conflicts (line $CONFLICTS) then use 'hg resolve --mark'"
  exit 1
fi

exit 0