tests/test-check-module-imports.t

includematcher: separate "parents" from "dirs"

A future patch will make use of this separation so that we can make more
intelligent decisions about what to investigate/load when the matcher is in use.

Currently, even with this patch, we typically use the 'visitdir' call to identify if
we can skip some directory, something along the lines of:

    for f in all_items:
        if match.visitdir(f):
           <do stuff>

This can be slower than we'd like if there are a lot of items; it requires N
calls to match.visitdir in the best case.  Commonly, especially with 'narrow',
we have a situation where we do some work for the directory, possibly just
loading it from disk (when using treemanifests) and then check if we should be
interacting with it at all, which can be a huge slowdown in some pathological
cases.

Differential Revision: https://phab.mercurial-scm.org/D4129

#require test-repo

  $ . "$TESTDIR/helpers-testrepo.sh"
  $ import_checker="$TESTDIR"/../contrib/import-checker.py

  $ cd "$TESTDIR"/..

There are a handful of cases here that require renaming a module so it
doesn't overlap with a stdlib module name. There are also some cycles
here that we should still endeavor to fix, and some cycles will be
hidden by deduplication algorithm in the cycle detector, so fixing
these may expose other cycles.

Known-bad files are excluded by -X as some of them would produce unstable
outputs, which should be fixed later.

  $ testrepohg locate 'set:**.py or grep(r"^#!.*?python")' \
  > 'tests/**.t' \
  > -X hgweb.cgi \
  > -X setup.py \
  > -X contrib/debugshell.py \
  > -X contrib/hgweb.fcgi \
  > -X contrib/packaging/hg-docker \
  > -X contrib/python-zstandard/ \
  > -X contrib/win32/hgwebdir_wsgi.py \
  > -X doc/gendoc.py \
  > -X doc/hgmanpage.py \
  > -X i18n/posplit \
  > -X mercurial/thirdparty \
  > -X tests/hypothesishelpers.py \
  > -X tests/test-check-interfaces.py \
  > -X tests/test-commit-interactive.t \
  > -X tests/test-contrib-check-code.t \
  > -X tests/test-demandimport.py \
  > -X tests/test-extension.t \
  > -X tests/test-hghave.t \
  > -X tests/test-hgweb-auth.py \
  > -X tests/test-hgweb-no-path-info.t \
  > -X tests/test-hgweb-no-request-uri.t \
  > -X tests/test-hgweb-non-interactive.t \
  > -X tests/test-hook.t \
  > -X tests/test-import.t \
  > -X tests/test-imports-checker.t \
  > -X tests/test-lock.py \
  > -X tests/test-verify-repo-operations.py \
  > | sed 's-\\-/-g' | $PYTHON "$import_checker" -