hgeditor

statprof: separate functions and "line", assume 4 digit line numbers

Previously, the profile output looked like this (I've removed many lines that
are mostly inconsequential):

```
| 100.0%  0.02s  hg:             <module>          line 43:  dispatch.run()
| 100.0%  0.02s  dispatch.py:    run               line 115:  status = dispatch(req)
| 100.0%  0.02s  dispatch.py:    _runcatchfunc     line 432:  return _dispatch(req)
 \ 50.0%  0.01s  dispatch.py:    _dispatch         line 1228:  return runcommand(
   | 50.0%  0.01s  dispatch.py:    runcommand      line 883:  ret = _runcommand(ui, optio...
   | 50.0%  0.01s  dispatch.py:    _runcommand     line 1240:  return cmdfunc()
   | 50.0%  0.01s  localrepo.py:   __getitem__     line 1670:  quick_access = self._quick_...
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeidline 1650:  return self._quick_access_c...
   | 50.0%  0.01s  localrepo.py:   __get__         line 179:  return getattr(unfi, self.n...
   | 50.0%  0.01s  util.py:        __get__         line 1747:  result = self.func(obj)
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid_wcline  1611:  cl = self.unfiltered().chan...
   | 50.0%  0.01s  localrepo.py:   __get__         line 110:  return super(_basefilecache...
   | 50.0%  0.01s  util.py:        __getattribute__line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_moduleline            783:
   | 50.0%  0.01s  <frozen importlib._bootstrap>: _call_with_frames_removedline                 219:
   | 50.0%  0.01s  changelog.py:   <module>        line 376:  class changelog(revlog.revl...
   | 50.0%  0.01s  util.py:        __getattribute__line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_moduleline            779:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: get_codeline         868:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: path_statsline           1012:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: _path_statline           87:
```

This has a few problems, though I'm only addressing some of them.

1.  If the stuff before "line ###" is long, there's no separation between the
    function name and the "line" string.
2.  If the stuff before "line ###" is really long, there's excessive separation
    between the "line" string and the line number.
3.  We frequently have 4-digit line numbers, the code on the right wasn't
    dynamically indented and ended up quite messy looking.

To solve these problems, I've added a ", " prefix before "line" iff it would
otherwise not have any separation such as spaces. I've added a 'max' so that we
never use a negative width (which is the cause of problem #2 above), and I've
added a default assumption of 4 digit line numbers (but again using a 'max' so
this shouldn't cause problems if we go beyond that.

With these changes, it now looks like this:

```
| 100.0%  0.02s  hg:             <module>          line 43:   dispatch.run()
| 100.0%  0.02s  dispatch.py:    run               line 115:  status = dispatch(req)
| 100.0%  0.02s  dispatch.py:    _runcatchfunc     line 432:  return _dispatch(req)
 \ 50.0%  0.01s  dispatch.py:    _dispatch         line 1228: return runcommand(
   | 50.0%  0.01s  dispatch.py:    runcommand      line 883:  ret = _runcommand(ui, optio...
   | 50.0%  0.01s  dispatch.py:    _runcommand     line 1240: return cmdfunc()
   | 50.0%  0.01s  localrepo.py:   __getitem__     line 1670: quick_access = self._quick_...
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid, line 1650: return self._quick_access_c...
   | 50.0%  0.01s  localrepo.py:   __get__         line 179:  return getattr(unfi, self.n...
   | 50.0%  0.01s  util.py:        __get__         line 1747: result = self.func(obj)
   | 50.0%  0.01s  localrepo.py:   _quick_access_changeid_wc, line 1611: cl = self.unfiltered().chan...
   | 50.0%  0.01s  localrepo.py:   __get__         line 110:  return super(_basefilecache...
   | 50.0%  0.01s  util.py:        __getattribute__, line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_module, line 783:
   | 50.0%  0.01s  <frozen importlib._bootstrap>: _call_with_frames_removed, line 219:
   | 50.0%  0.01s  changelog.py:   <module>        line 376:  class changelog(revlog.revl...
   | 50.0%  0.01s  util.py:        __getattribute__, line 245:  self.__spec__.loader.exec_m...
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: exec_module, line 779:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: get_code, line 868:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: path_stats, line 1012:
   | 50.0%  0.01s  <frozen importlib._bootstrap_external>: _path_stat, line 87:
```

Differential Revision: https://phab.mercurial-scm.org/D9511

#!/bin/sh
#
# This is an example of using HGEDITOR to create of diff to review the
# changes while committing.

# 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 $?