use test skip logic

Author: alimanfoo

numcodecs/tests/test_lzma.py

@@ -1,54 +1,49 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import, print_function, division
+import itertools
 
 
-_lzma = None
+import nose
+import numpy as np
+
 try:
-    import lzma as _lzma
-except ImportError:  # pragma: no cover
-    try:
-        from backports import lzma as _lzma
-    except ImportError:
-        pass
-
-
-if _lzma:
-
-    import itertools
-    import numpy as np
-    from numcodecs.lzma import LZMA
-    from numcodecs.tests.common import check_encode_decode, check_config, \
-        check_repr
-
-    codecs = [
-        LZMA(),
-        LZMA(preset=1),
-        LZMA(preset=5),
-        LZMA(preset=9),
-        LZMA(format=_lzma.FORMAT_RAW,
-             filters=[dict(id=_lzma.FILTER_LZMA2, preset=1)])
-    ]
-
-    # mix of dtypes: integer, float, bool, string
-    # mix of shapes: 1D, 2D, 3D
-    # mix of orders: C, F
-    arrays = [
-        np.arange(1000, dtype='i4'),
-        np.linspace(1000, 1001, 1000, dtype='f8'),
-        np.random.normal(loc=1000, scale=1, size=(100, 10)),
-        np.random.randint(0, 2, size=1000, dtype=bool).reshape(100, 10,
-                                                               order='F'),
-        np.random.choice([b'a', b'bb', b'ccc'], size=1000).reshape(10, 10, 10)
-    ]
-
-    def test_encode_decode():
-        for arr, codec in itertools.product(arrays, codecs):
-            check_encode_decode(arr, codec)
-
-    def test_config():
-        codec = LZMA(preset=1, format=_lzma.FORMAT_XZ,
-                     check=_lzma.CHECK_NONE, filters=None)
-        check_config(codec)
-
-    def test_repr():
-        check_repr('LZMA(format=1, check=0, preset=1, filters=None)')
+    from numcodecs.lzma import LZMA, _lzma
+except ImportError:
+    raise nose.SkipTest("LZMA not available")
+
+from numcodecs.tests.common import check_encode_decode, check_config, check_repr
+
+
+codecs = [
+    LZMA(),
+    LZMA(preset=1),
+    LZMA(preset=5),
+    LZMA(preset=9),
+    LZMA(format=_lzma.FORMAT_RAW, filters=[dict(id=_lzma.FILTER_LZMA2, preset=1)])
+]
+
+
+# mix of dtypes: integer, float, bool, string
+# mix of shapes: 1D, 2D, 3D
+# mix of orders: C, F
+arrays = [
+    np.arange(1000, dtype='i4'),
+    np.linspace(1000, 1001, 1000, dtype='f8'),
+    np.random.normal(loc=1000, scale=1, size=(100, 10)),
+    np.random.randint(0, 2, size=1000, dtype=bool).reshape(100, 10, order='F'),
+    np.random.choice([b'a', b'bb', b'ccc'], size=1000).reshape(10, 10, 10)
+]
+
+
+def test_encode_decode():
+    for arr, codec in itertools.product(arrays, codecs):
+        check_encode_decode(arr, codec)
+
+
+def test_config():
+    codec = LZMA(preset=1, format=_lzma.FORMAT_XZ, check=_lzma.CHECK_NONE, filters=None)
+    check_config(codec)
+
+
+def test_repr():
+    check_repr('LZMA(format=1, check=0, preset=1, filters=None)')