Fix missing config errors when running test suite (#1365)

* Fix missing config errors when running test suite

Fixes GH1358, GH1353

The approach I took here is to *not* package `conftest.py` with the xarray
distribution, but rather make the test suite robust to it's absence.

Also, as suggested by QuLogic in GH1336, switched from using a custom decorator
for `--run-slow` to just using `@pytest.mark.slow`.

Finally, I speed-up the test_dataset.test_rolling_reduce tests (from ~55 to ~17
seconds when bottleneck is not installed) and marked them as slow. It would be
nice to get them running in a few seconds or less, but we can save that for
later. On my laptop, the whole test suite now runs with `-k 'not slow'` in
36 seconds, which is not great, but acceptable.

CC pwolfram jhamman ghisvail

* fix typo netCDF4 -> has_netCDF4

conftest.py

@@ -5,5 +5,3 @@ def pytest_addoption(parser):
     """Add command-line flags for pytest."""
     parser.addoption("--run-flaky", action="store_true",
                      help="runs flaky tests")
-    parser.addoption("--skip-slow", action="store_true",
-                     help="skips slow tests")

doc/whats-new.rst

@@ -33,6 +33,11 @@ Bug fixes
   (:issue:`1359`).
   `Stephan Hoyer <https://github.com/shoyer>`_.
 
+- Ensure test suite works when runs from an installed version of xarray
+  (:issue:`1336`). Use ``@pytest.mark.slow`` instead of a custom flag to mark
+  slow tests.
+  By `Stephan Hoyer <https://github.com/shoyer>`_
+
 .. _whats-new.0.9.2:
 
 v0.9.2 (2 April, 2017)

xarray/tests/__init__.py

@@ -78,49 +78,36 @@
 
 # slighly simpler construction that the full functions.
 # Generally `pytest.importorskip('package')` inline is even easier
-requires_matplotlib = pytest.mark.skipif(not has_matplotlib, reason='requires matplotlib')
+requires_matplotlib = pytest.mark.skipif(
+    not has_matplotlib, reason='requires matplotlib')
+requires_scipy = pytest.mark.skipif(
+    not has_scipy, reason='requires scipy')
+requires_pydap = pytest.mark.skipif(
+    not has_pydap, reason='requires pydap')
+requires_netCDF4 = pytest.mark.skipif(
+    not has_netCDF4, reason='requires netCDF4')
+requires_h5netcdf = pytest.mark.skipif(
+    not has_h5netcdf, reason='requires h5netcdf')
+requires_pynio = pytest.mark.skipif(
+    not has_pynio, reason='requires pynio')
+requires_scipy_or_netCDF4 = pytest.mark.skipif(
+    not has_scipy and not has_netCDF4, reason='requires scipy or netCDF4')
+requires_dask = pytest.mark.skipif(
+    not has_dask, reason='requires dask')
+requires_bottleneck = pytest.mark.skipif(
+    not has_bottleneck, reason='requires bottleneck')
 
 
-def requires_scipy(test):
-    return test if has_scipy else pytest.mark.skip('requires scipy')(test)
-
-
-def requires_pydap(test):
-    return test if has_pydap else pytest.mark.skip('requires pydap.client')(test)
-
-
-def requires_netCDF4(test):
-    return test if has_netCDF4 else pytest.mark.skip('requires netCDF4')(test)
-
-
-def requires_h5netcdf(test):
-    return test if has_h5netcdf else pytest.mark.skip('requires h5netcdf')(test)
-
-
-def requires_pynio(test):
-    return test if has_pynio else pytest.mark.skip('requires pynio')(test)
-
-
-def requires_scipy_or_netCDF4(test):
-    return (test if has_scipy or has_netCDF4
-            else pytest.mark.skip('requires scipy or netCDF4')(test))
-
-
-def requires_dask(test):
-    return test if has_dask else pytest.mark.skip('requires dask')(test)
-
-
-def requires_bottleneck(test):
-    return test if has_bottleneck else pytest.mark.skip('requires bottleneck')(test)
-
+try:
+    _SKIP_FLAKY = not pytest.config.getoption("--run-flaky")
+except ValueError:
+    # Can't get config from pytest, e.g., because xarray is installed instead
+    # of being run from a development version (and hence conftests.py is not
+    # available). Don't run flaky tests.
+    _SKIP_FLAKY = True
 
 flaky = pytest.mark.skipif(
-    not pytest.config.getoption("--run-flaky"),
-    reason="set --run-flaky option to run flaky tests")
-
-slow = pytest.mark.skipif(
-    pytest.config.getoption("--skip-slow"),
-    reason="set --skip-slow option to run slow tests")
+    _SKIP_FLAKY, reason="set --run-flaky option to run flaky tests")
 
 
 class TestCase(unittest.TestCase):

xarray/tests/test_backends.py

@@ -27,7 +27,7 @@
 from . import (TestCase, requires_scipy, requires_netCDF4, requires_pydap,
                requires_scipy_or_netCDF4, requires_dask, requires_h5netcdf,
                requires_pynio, has_netCDF4, has_scipy, assert_allclose,
-               flaky, slow)
+               flaky)
 from .test_dataset import create_test_data
 
 try:
@@ -1118,21 +1118,21 @@ def test_4_autoclose_h5netcdf(self):
     @requires_dask
     @requires_netCDF4
     @flaky
-    @slow
+    @pytest.mark.slow
     def test_1_open_large_num_files_netcdf4(self):
         self.validate_open_mfdataset_large_num_files(engine=['netcdf4'])
 
     @requires_dask
     @requires_scipy
     @flaky
-    @slow
+    @pytest.mark.slow
     def test_2_open_large_num_files_scipy(self):
         self.validate_open_mfdataset_large_num_files(engine=['scipy'])
 
     @requires_dask
     @requires_pynio
     @flaky
-    @slow
+    @pytest.mark.slow
     def test_3_open_large_num_files_pynio(self):
         self.validate_open_mfdataset_large_num_files(engine=['pynio'])
 
@@ -1142,7 +1142,7 @@ def test_3_open_large_num_files_pynio(self):
     @requires_h5netcdf
     @flaky
     @pytest.mark.xfail
-    @slow
+    @pytest.mark.slow
     def test_4_open_large_num_files_h5netcdf(self):
         self.validate_open_mfdataset_large_num_files(engine=['h5netcdf'])
 

xarray/tests/test_dataset.py

@@ -3342,21 +3342,21 @@ def test_dir_unicode(data_set):
 @pytest.fixture(params=[1])
 def ds(request):
     if request.param == 1:
-        return Dataset({'z1': (['y', 'x'], np.random.randn(5, 20)),
-                        'z2': (['time', 'y'], np.random.randn(30, 5))},
-                       {'x': ('x', np.linspace(0, 1.0, 20)),
-                        'time': ('time', np.linspace(0, 1.0, 30)),
-                        'c': ('y', ['a', 'b', 'c', 'd', 'e']),
-                        'y': range(5)})
+        return Dataset({'z1': (['y', 'x'], np.random.randn(2, 8)),
+                        'z2': (['time', 'y'], np.random.randn(10, 2))},
+                       {'x': ('x', np.linspace(0, 1.0, 8)),
+                        'time': ('time', np.linspace(0, 1.0, 10)),
+                        'c': ('y', ['a', 'b']),
+                        'y': range(2)})
 
     if request.param == 2:
-        return Dataset({'z1': (['time', 'y'], np.random.randn(30, 5)),
-                        'z2': (['time'], np.random.randn(30)),
-                        'z3': (['x', 'time'], np.random.randn(20, 30))},
-                       {'x': ('x', np.linspace(0, 1.0, 20)),
-                        'time': ('time', np.linspace(0, 1.0, 30)),
-                        'c': ('y', ['a', 'b', 'c', 'd', 'e']),
-                        'y': range(5)})
+        return Dataset({'z1': (['time', 'y'], np.random.randn(10, 2)),
+                        'z2': (['time'], np.random.randn(10)),
+                        'z3': (['x', 'time'], np.random.randn(8, 10))},
+                       {'x': ('x', np.linspace(0, 1.0, 8)),
+                        'time': ('time', np.linspace(0, 1.0, 10)),
+                        'c': ('y', ['a', 'b']),
+                        'y': range(2)})
 
 
 def test_rolling_properties(ds):
@@ -3440,6 +3440,7 @@ def test_rolling_pandas_compat(center, window, min_periods):
                                ds_rolling['index'])
 
 
+@pytest.mark.slow
 @pytest.mark.parametrize('ds', (1, 2), indirect=True)
 @pytest.mark.parametrize('center', (True, False))
 @pytest.mark.parametrize('min_periods', (None, 1, 2, 3))