contrib/editmerge

dirstate: drop explicit files that shouldn't match (BC) (issue4679)

Before, wctx.walk() could include files excluded by -X pattern, which
disagrees with wctx.matches() and ctx.walk()/matches() behavior. This patch
fixes the problem by testing stat results against the matcher if the matcher
may contain false paths.

I have no idea if the fix should be made before the workaround for case-
insensitive filesystems, but that shouldn't matter since match.anypats()
means 'not match.isexact()'.

This patch also makes narrow and sparse extensions to not exclude explicit
paths on walk() because they appear to depend on the buggy behavior.

More detailed analysis about this issue by Martin von Zweigbergk:

"I think it's just an unintended consequence of how the dirstate walk works,
but I'm not sure. The exception for explicit files also bothered me when I
was working on the matcher code a year or so ago. I actually added the
exception to the matcher code because I thought it was always working like
that (not just for dirstate) in a83a7d27911e (match: handle excludes using
new differencematcher, 2017-05-16). It was only recently that Yuya realized
that it used to be inconsistent and that I probably made it consistently bad
because I didn't realize it was inconsistent to start with, see 821d8a5ab4ff
(match: do not weirdly include explicit files excluded by -X option,
2018-01-16)."

.. bc::

   Working-directory commands now respect ``-X PATTERN`` no matter if PATTERN
   matches explicitly-specified FILEs. For example, ``hg add foo -X foo`` no
   longer add the file ``foo``.

#!/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