TST: pytest deprecation warnings GH17197 (pandas-dev#17253)

Test parameters with marks are updated according to the updated API of
Pytest.
https://docs.pytest.org/en/latest/changelog.html#pytest-3-2-0-2017-07-30
https://docs.pytest.org/en/latest/parametrize.html

Author: swyoon

Diff for: appveyor.yml

@@ -72,7 +72,7 @@ install:
   - cmd: conda info -a
 
   # create our env
-  - cmd: conda create -n pandas python=%PYTHON_VERSION% cython pytest pytest-xdist
+  - cmd: conda create -n pandas python=%PYTHON_VERSION% cython pytest>=3.1.0 pytest-xdist
   - cmd: activate pandas
   - SET REQ=ci\requirements-%PYTHON_VERSION%_WIN.run
   - cmd: echo "installing requirements from %REQ%"

Diff for: ci/install_circle.sh

@@ -64,7 +64,7 @@ fi
 # create envbuild deps
 echo "[create env: ${REQ_BUILD}]"
 time conda create -n pandas -q --file=${REQ_BUILD} || exit 1
-time conda install -n pandas pytest || exit 1
+time conda install -n pandas pytest>=3.1.0 || exit 1
 
 source activate pandas
 

Diff for: ci/install_travis.sh

@@ -103,7 +103,7 @@ if [ -e ${REQ} ]; then
     time bash $REQ || exit 1
 fi
 
-time conda install -n pandas pytest
+time conda install -n pandas pytest>=3.1.0
 time pip install pytest-xdist
 
 if [ "$LINT" ]; then

Diff for: ci/requirements_all.txt

@@ -1,4 +1,4 @@
-pytest
+pytest>=3.1.0
 pytest-cov
 pytest-xdist
 flake8

Diff for: ci/requirements_dev.txt

@@ -2,6 +2,6 @@ python-dateutil
 pytz
 numpy
 cython
-pytest
+pytest>=3.1.0
 pytest-cov
 flake8

Diff for: doc/source/contributing.rst

@@ -598,6 +598,10 @@ Like many packages, *pandas* uses `pytest
 extensions in `numpy.testing
 <http://docs.scipy.org/doc/numpy/reference/routines.testing.html>`_.
 
+.. note::
+
+   The earliest supported pytest version is 3.1.0.
+
 Writing tests
 ~~~~~~~~~~~~~
 
@@ -654,7 +658,9 @@ Using ``pytest``
 Here is an example of a self-contained set of tests that illustrate multiple features that we like to use.
 
 - functional style: tests are like ``test_*`` and *only* take arguments that are either fixtures or parameters
+- ``pytest.mark`` can be used to set metadata on test functions, e.g. ``skip`` or ``xfail``.
 - using ``parametrize``: allow testing of multiple cases
+- to set a mark on a parameter, ``pytest.param(..., marks=...)`` syntax should be used
 - ``fixture``, code for object construction, on a per-test basis
 - using bare ``assert`` for scalars and truth-testing
 - ``tm.assert_series_equal`` (and its counter part ``tm.assert_frame_equal``), for pandas object comparisons.
@@ -673,6 +679,13 @@ We would name this file ``test_cool_feature.py`` and put in an appropriate place
    def test_dtypes(dtype):
        assert str(np.dtype(dtype)) == dtype
 
+   @pytest.mark.parametrize('dtype', ['float32',
+       pytest.param('int16', marks=pytest.mark.skip),
+       pytest.param('int32',
+                    marks=pytest.mark.xfail(reason='to show how it works'))])
+   def test_mark(dtype):
+       assert str(np.dtype(dtype)) == 'float32'
+
    @pytest.fixture
    def series():
        return pd.Series([1, 2, 3])
@@ -695,13 +708,16 @@ A test run of this yields
 
    ((pandas) bash-3.2$ pytest  test_cool_feature.py  -v
    =========================== test session starts ===========================
-   platform darwin -- Python 3.5.2, pytest-3.0.5, py-1.4.31, pluggy-0.4.0
-   collected 8 items
+   platform darwin -- Python 3.6.2, pytest-3.2.1, py-1.4.31, pluggy-0.4.0
+   collected 11 items
 
    tester.py::test_dtypes[int8] PASSED
    tester.py::test_dtypes[int16] PASSED
    tester.py::test_dtypes[int32] PASSED
    tester.py::test_dtypes[int64] PASSED
+   tester.py::test_mark[float32] PASSED
+   tester.py::test_mark[int16] SKIPPED
+   tester.py::test_mark[int32] xfail
    tester.py::test_series[int8] PASSED
    tester.py::test_series[int16] PASSED
    tester.py::test_series[int32] PASSED
@@ -714,8 +730,8 @@ Tests that we have ``parametrized`` are now accessible via the test name, for ex
 
    ((pandas) bash-3.2$ pytest  test_cool_feature.py  -v -k int8
    =========================== test session starts ===========================
-   platform darwin -- Python 3.5.2, pytest-3.0.5, py-1.4.31, pluggy-0.4.0
-   collected 8 items
+   platform darwin -- Python 3.6.2, pytest-3.2.1, py-1.4.31, pluggy-0.4.0
+   collected 11 items
 
    test_cool_feature.py::test_dtypes[int8] PASSED
    test_cool_feature.py::test_series[int8] PASSED

Diff for: pandas/tests/computation/test_eval.py

@@ -38,13 +38,14 @@
 
 
 @pytest.fixture(params=(
-    pytest.mark.skipif(engine == 'numexpr' and not _USE_NUMEXPR,
-                       reason='numexpr enabled->{enabled}, '
-                              'installed->{installed}'.format(
-                                  enabled=_USE_NUMEXPR,
-                                  installed=_NUMEXPR_INSTALLED))(engine)
-                       for engine in _engines  # noqa
-))
+    pytest.param(engine,
+                 marks=pytest.mark.skipif(
+                     engine == 'numexpr' and not _USE_NUMEXPR,
+                     reason='numexpr enabled->{enabled}, '
+                            'installed->{installed}'.format(
+                                enabled=_USE_NUMEXPR,
+                                installed=_NUMEXPR_INSTALLED)))
+                 for engine in _engines))  # noqa
 def engine(request):
     return request.param
 

Diff for: pandas/tests/io/parser/test_network.py

@@ -23,8 +23,10 @@ def salaries_table():
 @pytest.mark.parametrize(
     "compression,extension",
     [('gzip', '.gz'), ('bz2', '.bz2'), ('zip', '.zip'),
-     pytest.mark.skipif(not tm._check_if_lzma(),
-                        reason='need backports.lzma to run')(('xz', '.xz'))])
+     pytest.param('xz', '.xz',
+                  marks=pytest.mark.skipif(not tm._check_if_lzma(),
+                                           reason='need backports.lzma '
+                                                  'to run'))])
 @pytest.mark.parametrize('mode', ['explicit', 'infer'])
 @pytest.mark.parametrize('engine', ['python', 'c'])
 def test_compressed_urls(salaries_table, compression, extension, mode, engine):

Diff for: pandas/tests/io/test_excel.py

@@ -2400,8 +2400,10 @@ def check_called(func):
 
 
 @pytest.mark.parametrize('engine', [
-    pytest.mark.xfail('xlwt', reason='xlwt does not support '
-                                     'openpyxl-compatible style dicts'),
+    pytest.param('xlwt',
+                 marks=pytest.mark.xfail(reason='xlwt does not support '
+                                                'openpyxl-compatible '
+                                                'style dicts')),
     'xlsxwriter',
     'openpyxl',
 ])

Diff for: pandas/tests/io/test_parquet.py

@@ -26,10 +26,14 @@
 
 # setup engines & skips
 @pytest.fixture(params=[
-    pytest.mark.skipif(not _HAVE_FASTPARQUET,
-                       reason='fastparquet is not installed')('fastparquet'),
-    pytest.mark.skipif(not _HAVE_PYARROW,
-                       reason='pyarrow is not installed')('pyarrow')])
+    pytest.param('fastparquet',
+                 marks=pytest.mark.skipif(not _HAVE_FASTPARQUET,
+                                          reason='fastparquet is '
+                                                 'not installed')),
+    pytest.param('pyarrow',
+                 marks=pytest.mark.skipif(not _HAVE_PYARROW,
+                                          reason='pyarrow is '
+                                                 'not installed'))])
 def engine(request):
     return request.param
 

Diff for: pandas/tests/test_window.py

@@ -530,8 +530,9 @@ def test_numpy_compat(self):
 
     @pytest.mark.parametrize(
         'expander',
-        [1, pytest.mark.xfail(
-            reason='GH 16425 expanding with offset not supported')('1s')])
+        [1, pytest.param('ls', marks=pytest.mark.xfail(
+                         reason='GH 16425 expanding with '
+                                'offset not supported'))])
     def test_empty_df_expanding(self, expander):
         # GH 15819 Verifies that datetime and integer expanding windows can be
         # applied to empty DataFrames