Layer Selection
===============

We can select which layers to run using the --layer option:

    >>> import os.path, sys
    >>> directory_with_tests = os.path.join(this_directory, 'testrunner-ex')
    >>> defaults = [
    ...     '--path', directory_with_tests,
    ...     '--tests-pattern', '^sampletestsf?$',
    ...     ]

    >>> sys.argv = 'test --layer 112 --layer unit'.split()
    >>> from zope.testing import testrunner
    >>> testrunner.run(defaults)
    Running unit tests:
      Ran 192 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer112 tests:
      Set up samplelayers.Layerx in N.NNN seconds.
      Set up samplelayers.Layer1 in N.NNN seconds.
      Set up samplelayers.Layer11 in N.NNN seconds.
      Set up samplelayers.Layer112 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Tearing down left over layers:
      Tear down samplelayers.Layer112 in N.NNN seconds.
      Tear down samplelayers.Layerx in N.NNN seconds.
      Tear down samplelayers.Layer11 in N.NNN seconds.
      Tear down samplelayers.Layer1 in N.NNN seconds.
    Total: 226 tests, 0 failures, 0 errors
    False

We can also specify that we want to run only the unit tests:

    >>> sys.argv = 'test -u'.split()
    >>> testrunner.run(defaults)
    Running unit tests:
      Ran 192 tests with 0 failures and 0 errors in 0.033 seconds.
    False

Or that we want to run all of the tests except for the unit tests:

    >>> sys.argv = 'test -f'.split()
    >>> testrunner.run(defaults)
    Running samplelayers.Layer1 tests:
      Set up samplelayers.Layer1 in N.NNN seconds.
      Ran 9 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer11 tests:
      Set up samplelayers.Layer11 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer111 tests:
      Set up samplelayers.Layerx in N.NNN seconds.
      Set up samplelayers.Layer111 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer112 tests:
      Tear down samplelayers.Layer111 in N.NNN seconds.
      Set up samplelayers.Layer112 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer12 tests:
      Tear down samplelayers.Layer112 in N.NNN seconds.
      Tear down samplelayers.Layerx in N.NNN seconds.
      Tear down samplelayers.Layer11 in N.NNN seconds.
      Set up samplelayers.Layer12 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer121 tests:
      Set up samplelayers.Layer121 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Running samplelayers.Layer122 tests:
      Tear down samplelayers.Layer121 in N.NNN seconds.
      Set up samplelayers.Layer122 in N.NNN seconds.
      Ran 34 tests with 0 failures and 0 errors in N.NNN seconds.
    Tearing down left over layers:
      Tear down samplelayers.Layer122 in N.NNN seconds.
      Tear down samplelayers.Layer12 in N.NNN seconds.
      Tear down samplelayers.Layer1 in N.NNN seconds.
    Total: 213 tests, 0 failures, 0 errors
    False