test_filesystem_with_cli_in_subprocess and test_version_no_noise fail because of third-party use of deprecated APIs

[exarkun]

Traceback (most recent call last):
testtools.testresult.real._StringException: Traceback (most recent call last):
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/internet/defer.py", line 654, in _runCallbacks
    current.result = callback(current.result, *args, **kw)
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/allmydata/test/test_system.py", line 2439, in _check_succeeded
    self.failUnlessEqual(err, "")
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/trial/_synctest.py", line 434, in assertEqual
    super(_Assertions, self).assertEqual(first, second, msg)
  File "/usr/lib/python2.7/unittest/case.py", line 513, in assertEqual
    assertion_func(first, second, msg=msg)
  File "/usr/lib/python2.7/unittest/case.py", line 506, in _baseAssertEqual
    raise self.failureException(msg)
twisted.trial.unittest.FailTest: '/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/internet/address.py:101: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(hash=False, repr=False, cmp=False)\n/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/automat/_methodical.py:209: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(cmp=False, hash=False)\n/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/automat/_methodical.py:288: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(cmp=False, hash=False)\n' != ''

and

Traceback (most recent call last):
testtools.testresult.real._StringException: Traceback (most recent call last):
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/internet/defer.py", line 654, in _runCallbacks
    current.result = callback(current.result, *args, **kw)
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/allmydata/test/test_runner.py", line 182, in _cb
    and "from pkg_resources import load_entry_point" not in line)], str(res))
  File "/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/trial/_synctest.py", line 386, in assertFalse
    super(_Assertions, self).assertFalse(condition, msg)
  File "/usr/lib/python2.7/unittest/case.py", line 416, in assertFalse
    raise self.failureException(msg)
twisted.trial.unittest.FailTest: ("tahoe-lafs: 1.13.0.post1221 [master: 393771d4f30d70c47f89047e88f8419020904682]\nfoolscap: 0.13.1+4.g5cff0bc\nzfec: 1.5.3\nTwisted: 19.7.0dev0\nNevow: 0.14.4\nzope.interface: unknown\npython: 2.7.13\nplatform: Linux-debian_9.11-x86_64-64bit\npyOpenSSL: 19.0.0\nOpenSSL: 1.1.1d [ 10 Sep 2019]\npyasn1: 0.4.7\nservice-identity: 18.1.0\ncharacteristic: None [(<type 'exceptions.ImportError'>, 'No module named characteristic', ('/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/allmydata/version_checks.py', 356, '_get_package_versions_and_locations', '__import__(modulename)'))]\npyasn1-modules: 0.2.7\ncryptography: 2.8\ncffi: 1.13.0\nsix: 1.12.0\nenum34: 1.1.6\npycparser: 2.19\nPyYAML: 5.1.2\nmagic-wormhole: 0.11.2\nsetuptools: 41.0.1\neliot: 1.7.0\nattrs: 19.3.0\nautobahn: 19.10.1\nconstantly: 15.1.0 [according to pkg_resources]\nidna: 2.8 [according to pkg_resources]\nautomat: 0.8.0 [according to pkg_resources]\nhumanize: 0.5.1 [according to pkg_resources]\nipaddress: 1.0.23 [according to pkg_resources]\nappdirs: 1.4.3 [according to pkg_resources]\nbcrypt: 3.1.7 [according to pkg_resources]\nspake2: 0.8 [according to pkg_resources]\nboltons: 19.2.0 [according to pkg_resources]\nhkdf: 0.0.3 [according to pkg_resources]\ntxaio: 18.8.1 [according to pkg_resources]\npyrsistent: 0.15.4 [according to pkg_resources]\ntqdm: 4.36.1 [according to pkg_resources]\npynacl: 1.3.0 [according to pkg_resources]\nclick: 7.0 [according to pkg_resources]\nincremental: 17.5.0 [according to pkg_resources]\npyhamcrest: 1.9.0 [according to pkg_resources]\ntxtorcon: 19.1.0 [according to pkg_resources]\nhyperlink: 19.0.0 [according to pkg_resources]\n\nWarning: dependency 'characteristic' (version None imported from None) was not found by pkg_resources.\n\nFor debugging purposes, the PYTHONPATH was\n  None\ninstall_requires was\n  ['six>=1.10.0', 'cryptography>=2.6', 'attrs>=18.2.0', 'Twisted[conch,tls]>=16.6.0', 'eliot~=1.7', 'zope.interface!=3.6.3,!=3.6.4,>=3.6.0', 'zfec>=1.1.0', 'setuptools>=28.8.0', 'foolscap>=0.12.6', 'PyYAML>=3.11', 'autobahn>=19.5.2', 'Nevow>=0.11.1', 'magic-wormhole>=0.10.2']\nsys.path after importing pkg_resources was\n  :\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7/plat-x86_64-linux-gnu:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7/lib-tk:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7/lib-old:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7/lib-dynload:\n  /usr/lib/python2.7:\n  /usr/lib/python2.7/plat-x86_64-linux-gnu:\n  /usr/lib/python2.7/lib-tk:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages:\n  /tmp/tahoe-lafs.tox/upcoming-deprecations/lib/python2.7/site-packages\n\n", '/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/twisted/internet/address.py:101: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(hash=False, repr=False, cmp=False)\n/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/automat/_methodical.py:209: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(cmp=False, hash=False)\n/tmp/tahoe-lafs.tox/upcoming-deprecations/local/lib/python2.7/site-packages/automat/_methodical.py:288: DeprecationWarning: The usage of `cmp` is deprecated and will be removed on or after 2021-06-01.  Please use `eq` and `order` instead.\n  @attr.s(cmp=False, hash=False)\n', 0)

Tahoe-LAFS isn't provoking these warnings. Its dependencies are. The tests aren't intended to be related to deprecation warnings. They are broken as an unintended side effect.

[exarkun]

​https://github.com/tahoe-lafs/tahoe-lafs/pull/664

[exarkun]

Fixed in ​https://github.com/tahoe-lafs/tahoe-lafs/commit/5e25da3261a44e0c3d61684d65a894711a2c7170