tests.unit.test_lifecycle.CoreSetupTestCase.test_core_setup_if_docker_env fails

[Cris Dywan]

tests.unit.test_lifecycle.CoreSetupTestCase.test_core_setup_if_docker_env fails locally for me with this:

Both as part of the suite and individually with `python3 -m unittest run tests.unit.test_lifecycle.CoreSetupTestCase.test_core_setup_if_docker_env`.

FAIL: test_core_setup_if_docker_env (tests.unit.test_lifecycle.CoreSetupTestCase)
tests.unit.test_lifecycle.CoreSetupTestCase.test_core_setup_if_docker_env
----------------------------------------------------------------------
testtools.testresult.real._StringException: Empty attachments:
  pythonlogging:''

Traceback (most recent call last):
  File "/usr/lib/python3.5/unittest/mock.py", line 1157, in patched
    return func(*args, **keywargs)
  File "/home/rumo/dev/snapcraft/tests/unit/test_lifecycle.py", line 1515, in test_core_setup_if_docker_env
    FileContains(matcher=MatchesRegex(regex, flags=re.DOTALL)))
  File "/home/rumo/venv/snapcraft/lib/python3.5/site-packages/testtools/testcase.py", line 498, in assertThat
    raise mismatch_error
testtools.matchers._impl.MismatchError: 'mkdir -p /tmp/tmpsol__uqg/core\n/snap/snapcraft/current/usr/bin/unsquashfs -d /tmp/tmpsol__uqg/core/current /tmp/tmpsol__uqg/.cache/snapcraft/projects/snapcraft-core/snap_hashes/armhf/88c510ff6076cdabd32dd70edcc1cbb29e949e0c681488d35b4477070baa41a483f90da246f029477ab0a4e831e7e234\n' does not match /.*mkdir -p /tmp/tmpsol__uqg/core\nunsquashfs -d /tmp/tmpsol__uqg/core/current .*88c510ff6076cdabd32dd70edcc1cbb29e949e0c681488d35b4477070baa41a483f90da246f029477ab0a4e831e7e234\n/

[Seth Arnold (seth-arnold)]

On Thu, Mar 01, 2018 at 01:18:46PM -0000, Christian Dywan wrote:
> testtools.matchers._impl.MismatchError: 'mkdir -p /tmp/tmpsol__uqg/core\n/snap/snapcraft/current/usr/bin/unsquashfs -d /tmp/tmpsol__uqg/core/current /tmp/tmpsol__uqg/.cache/snapcraft/projects/snapcraft-core/snap_hashes/armhf/88c510ff6076cdabd32dd70edcc1cbb29e949e0c681488d35b4477070baa41a483f90da246f029477ab0a4e831e7e234\n' does not match /.*mkdir -p /tmp/tmpsol__uqg/core\nunsquashfs -d /tmp/tmpsol__uqg/core/current .*88c510ff6076cdabd32dd70edcc1cbb29e949e0c681488d35b4477070baa41a483f90da246f029477ab0a4e831e7e234\n/

Apologies if this is obvious, but there the \n in this line stands out
clear as day to me for a sceond and seemed relevant. I didn't want this to
go unnoticed otherwise.

Thanks