filectx: add isabsent method
This will indicate whether this filectx represents a file that is *not* in a
changectx. This will be used by merge and filemerge code to know about when a
conflict is a change/delete conflict.
While this is kind of hacky, it is the least bad of all the alternatives. Other
options considered but rejected include:
- isinstance(fctx, ...) -- not very Pythonic, doesn't support duck typing
- fctx.size() is None -- the 'size()' call on workingfilectxes causes a disk stat
- fctx.filenode() == nullid -- the semantics around filenode are incredibly
confusing. In particular, for workingfilectxes, filenode() is always None no
matter whether the file is present on disk or in either parent. Having different
behavior for None versus nullid in the merge code is just asking for pain.
Thanks to Pierre-Yves David for early review feedback here.
#!/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 https://mercurial-scm.org/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