Pytest 3.7.2 fails with ModuleNotFoundError on Python 3.6.

[ejolly]

I'm running into an issue with the latest version of pytest that was mentioned previously here #2287 and here #2132. Specifically with python 3.6.3 and pytest 3.7.2, the pytest command fails because it can't import anything properly. Critically, this is not an issue if I use pytest==3.6.1. This error is consistent on my local platform (Mac OS 10.11), on travis using a python 3.6 environment, and on a separate linux machine. It's currently breaking Travis CI for at least 2 other projects I develop/contribute to unless I specifically tell Travis to use pytest==3.6.1:

https://github.com/ejolly/pymer4
https://github.com/cosanlab/nltools

Running python -m pytest doesn't seem to work either. Is there a different way that testing should be conducted on newer version of pytest? Or some additional setup required? I've included just a log of testing on my local machine below with the pymer4 project, but am happy to include any more info required to help solve the issue.

Thanks in advance.

================================================ test session starts =================================================
platform darwin -- Python 3.6.3, pytest-3.7.2, py-1.5.4, pluggy-0.7.1
rootdir: /Users/Esh/Documents/Python/Cosan/pymer4, inifile:
collected 10 items

pymer4/tests/test_models.py EEEEEEEE                                                                           [ 80%]
pymer4/tests/test_simulate.py EE                                                                               [100%]

======================================================= ERRORS =======================================================
_________________________________________ ERROR at setup of test_gaussian_lm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x105407bf8>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
________________________________________ ERROR at setup of test_gaussian_lmm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x1104428c8>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
__________________________________________ ERROR at setup of test_post_hoc ___________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110609ae8>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
________________________________________ ERROR at setup of test_logistic_lmm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110609730>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
____________________________________________ ERROR at setup of test_anova ____________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x1104428c8>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
_________________________________________ ERROR at setup of test_poisson_lmm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110442f28>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
__________________________________________ ERROR at setup of test_gamma_lmm __________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110609620>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
____________________________________ ERROR at setup of test_inverse_gaussian_lmm _____________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110621730>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
_________________________________________ ERROR at setup of test_simulate_lm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110609730>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
________________________________________ ERROR at setup of test_simulate_lmm _________________________________________

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
>           mod = self.fspath.pyimport(ensuresyspath=importmode)

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:476:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = local('/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'), modname = 'pymer4.pymer4'
ensuresyspath = 'prepend'

    def pyimport(self, modname=None, ensuresyspath=True):
        """ return path as an imported python module.

            If modname is None, look for the containing package
            and construct an according module name.
            The module will be put/looked up in sys.modules.
            if ensuresyspath is True then the root dir for importing
            the file (taking __init__.py files into account) will
            be prepended to sys.path if it isn't there already.
            If ensuresyspath=="append" the root dir will be appended
            if it isn't already contained in sys.path.
            if ensuresyspath is False no modification of syspath happens.
            """
        if not self.check():
            raise py.error.ENOENT(self)

        pkgpath = None
        if modname is None:
            pkgpath = self.pypkgpath()
            if pkgpath is not None:
                pkgroot = pkgpath.dirpath()
                names = self.new(ext="").relto(pkgroot).split(self.sep)
                if names[-1] == "__init__":
                    names.pop()
                modname = ".".join(names)
            else:
                pkgroot = self.dirpath()
                modname = self.purebasename

            self._ensuresyspath(ensuresyspath, pkgroot)
>           __import__(modname)
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/py/_path/local.py:668: ModuleNotFoundError

During handling of the above exception, another exception occurred:

self = <CallInfo when='setup' exception: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/py...re your test modules/packages have valid Python names.
Traceback:
ModuleNotFoundError: No module named 'pymer4.pymer4'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x110621c80>, when = 'setup'
treat_keyboard_interrupt_as_exception = False

    def __init__(self, func, when, treat_keyboard_interrupt_as_exception=False):
        #: context of invocation: one of "setup", "call",
        #: "teardown", "memocollect"
        self.when = when
        self.start = time()
        try:
>           self.result = func()

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:201:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:183: in <lambda>
    lambda: ihook(item=item, **kwds),
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/hooks.py:258: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:67: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/Users/Esh/anaconda3/lib/python3.6/site-packages/pluggy/manager.py:61: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:104: in pytest_runtest_setup
    item.session._setupstate.prepare(item)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:366: in prepare
    py.builtin._reraise(*col._prepare_exc)
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/runner.py:370: in prepare
    col.setup()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:523: in setup
    setup_module = _get_xunit_setup_teardown(self.obj, "setUpModule")
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:269: in fget
    self._obj = obj = self._getobj()
/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:466: in _getobj
    return self._importtestmodule()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <Package '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4'>

    def _importtestmodule(self):
        # we assume we are only called once per module
        importmode = self.config.getoption("--import-mode")
        try:
            mod = self.fspath.pyimport(ensuresyspath=importmode)
        except SyntaxError:
            raise self.CollectError(
                _pytest._code.ExceptionInfo().getrepr(style="short")
            )
        except self.fspath.ImportMismatchError:
            e = sys.exc_info()[1]
            raise self.CollectError(
                "import file mismatch:\n"
                "imported module %r has this __file__ attribute:\n"
                "  %s\n"
                "which is not the same as the test file we want to collect:\n"
                "  %s\n"
                "HINT: remove __pycache__ / .pyc files and/or use a "
                "unique basename for your test file modules" % e.args
            )
        except ImportError:
            from _pytest._code.code import ExceptionInfo

            exc_info = ExceptionInfo()
            if self.config.getoption("verbose") < 2:
                exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short")
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = safe_str(exc_repr)
            raise self.CollectError(
                "ImportError while importing test module '{fspath}'.\n"
                "Hint: make sure your test modules/packages have valid Python names.\n"
                "Traceback:\n"
>               "{traceback}".format(fspath=self.fspath, traceback=formatted_tb)
            )
E           _pytest.nodes.Collector.CollectError: ImportError while importing test module '/Users/Esh/Documents/Python/Cosan/pymer4/pymer4/__init__.py'.
E           Hint: make sure your test modules/packages have valid Python names.
E           Traceback:
E           ModuleNotFoundError: No module named 'pymer4.pymer4'

/Users/Esh/anaconda3/lib/python3.6/site-packages/_pytest/python.py:508: CollectError
============================================== 10 error in 3.69 seconds ==============================================

[asottile]

I suspect the presence of __init__.py in the root directory is causing this. You shouldn't need that (it doesn't get packaged).

It's likely confusing pytest where the root of your code is?

[ejolly]

Ah I see, that seems to have solved it thanks a lot! Is there a reason why previous versions of pytest didn't get confused by this?

[asottile]

This is probably due to the new "package" discovery code. I'm not entirely sure though

[ejolly]

I see thanks for the info.