contrib/editmerge

import-checker: make imported_modules yield absolute dotted_name_of_path

This patch makes `imported_modules()` always yield absolute
`dotted_name_of_path()`-ed name by strict detection with
`fromlocal()`.

This change improves circular detection in some points:

  - locally defined modules, of which name collides against one of
    standard library, can be examined correctly

    For example, circular import related to `commands` is overlooked
    before this patch.

  - names not useful for circular detection are ignored

    Names below are also yielded before this patch:

      - module names of standard library (= not locally defined one)
      - non-module names (e.g. `node.nullid` of `from node import nullid`)

    These redundant names decrease performance of circular detection.

    For example, with files at 1ef96a3b8b89, average loops per file in
    `checkmod()` is reduced from 165 to 109.

  - `__init__` can be handled correctly in `checkmod()`

    For example, current implementation has problems below:

      - `from xxx import yyy` doesn't recognize `xxx.__init__` as imported

      - `xxx.__init__` imported via `import xxx` is treated as `xxx`,
        and circular detection is aborted, because `key` of such
        module name is not `xxx` but `xxx.__init__`

  - it is easy to enhance for `from . import xxx` style or so (in the
    future)

    Module name detection in `imported_modules()` can use information
    in `ast.ImportFrom` fully.

It is assumed that all locally defined modules are correctly specified
to `import-checker.py` at once.

Strictly speaking, when `from foo.bar.baz import module1` imports
`foo.bar.baz.module1` module, current `imported_modules()` yields only
`foo.bar.baz.__init__`, even though also `foo.__init__` and
`foo.bar.__init__` should be yielded to detect circular import
exactly.

But this limitation is reasonable one for improvement in this patch,
because current `__init__` files in Mercurial seems to be implemented
carefully.

#!/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