tests/test-module-imports.t

debugdirstate: don't hide date field with --nodate, just show 'set'/'unset'

The value of the dirstate date field cannot be used in tests and we thus have
to use debugdirstate with --nodate. It is however still very helpful to be able
to see whether the date field has been set or still is unset. The absence of
that information made it hard to debug some largefile dirstate issues.

This change _could_ make the test suite more unstable ... but that would be
places where the test suite or the code should be made more stable. (Note:
'unset' with the magic negative sizes is reliable. 'unset' for normal sizes
would probably not be reliable, but there is no such occurrences in the test
suite and it should thus be reliable.)

This output wastes more horizontal space in the --nodate output, but it also
makes things simpler that the output format always is the same. It is just a
debug command so let's keep it simple.

This code uses the ast module, which was new in 2.6, so we'll skip
this test on anything earlier.
  $ $PYTHON -c 'import sys ; assert sys.version_info >= (2, 6)' || exit 80

  $ import_checker="$TESTDIR"/../contrib/import-checker.py
Run the doctests from the import checker, and make sure
it's working correctly.
  $ TERM=dumb
  $ export TERM
  $ python -m doctest $import_checker

  $ cd "$TESTDIR"/..
  $ if hg identify -q > /dev/null 2>&1; then :
  > else
  >     echo "skipped: not a Mercurial working dir" >&2
  >     exit 80
  > fi

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.

  $ hg locate 'mercurial/**.py' | sed 's-\\-/-g' | xargs python "$import_checker"
  mercurial/dispatch.py mixed imports
     stdlib:    commands
     relative:  error, extensions, fancyopts, hg, hook, util
  mercurial/fileset.py mixed imports
     stdlib:    parser
     relative:  error, merge, util
  mercurial/revset.py mixed imports
     stdlib:    parser
     relative:  discovery, error, hbisect, phases, util
  mercurial/templater.py mixed imports
     stdlib:    parser
     relative:  config, error, templatefilters, templatekw, util
  mercurial/ui.py mixed imports
     stdlib:    formatter
     relative:  config, error, scmutil, util
  Import cycle: mercurial.cmdutil -> mercurial.context -> mercurial.subrepo -> mercurial.cmdutil -> mercurial.cmdutil