REF/TST: Add more pytest idiom to tests/resample

pandas/tests/resample/conftest.py

@@ -1,7 +1,16 @@
+import numpy as np
 import pytest
 
-from pandas.tests.resample.test_base import (
-    downsample_methods, resample_methods, upsample_methods)
+from pandas import Series
+from pandas.core.indexes.datetimes import date_range
+from pandas.core.indexes.period import period_range
+
+# The various methods we support
+downsample_methods = ['min', 'max', 'first', 'last', 'sum', 'mean', 'sem',
+                      'median', 'prod', 'var', 'std', 'ohlc', 'quantile']
+upsample_methods = ['count', 'size']
+series_methods = ['nunique']
+resample_methods = downsample_methods + upsample_methods + series_methods
 
 
 @pytest.fixture(params=downsample_methods)
@@ -20,3 +29,25 @@ def upsample_method(request):
 def resample_method(request):
     """Fixture for parametrization of Grouper resample methods."""
     return request.param
+
+
+@pytest.fixture()
+def simple_date_range_series():
+    """
+    Series with date range index and random data for test purposes.
+    """
+    def _simple_date_range_series(start, end, freq='D'):
+        rng = date_range(start, end, freq=freq)
+        return Series(np.random.randn(len(rng)), index=rng)
+    return _simple_date_range_series
+
+
+@pytest.fixture()
+def simple_period_range_series():
+    """
+    Series with period range index and random data for test purposes.
+    """
+    def _simple_period_range_series(start, end, freq='D'):
+        rng = period_range(start, end, freq=freq)
+        return Series(np.random.randn(len(rng)), index=rng)
+    return _simple_period_range_series

pandas/tests/resample/test_base.py

@@ -11,42 +11,14 @@
 import pandas as pd
 from pandas import DataFrame, Series
 from pandas.core.groupby.groupby import DataError
-from pandas.core.indexes.datetimes import date_range
-from pandas.core.indexes.period import PeriodIndex, period_range
+from pandas.core.indexes.period import PeriodIndex
 from pandas.core.indexes.timedeltas import TimedeltaIndex
 from pandas.core.resample import TimeGrouper
 import pandas.util.testing as tm
 from pandas.util.testing import (
     assert_almost_equal, assert_frame_equal, assert_index_equal,
     assert_series_equal)
 
-from pandas.tseries.offsets import BDay
-
-business_day_offset = BDay()
-
-# The various methods we support
-downsample_methods = ['min', 'max', 'first', 'last', 'sum', 'mean', 'sem',
-                      'median', 'prod', 'var', 'std', 'ohlc', 'quantile']
-upsample_methods = ['count', 'size']
-series_methods = ['nunique']
-resample_methods = downsample_methods + upsample_methods + series_methods
-
-
-def simple_date_range_series(start, end, freq='D'):
-    """
-    Series with date range index and random data for test purposes.
-    """
-    rng = date_range(start, end, freq=freq)
-    return Series(np.random.randn(len(rng)), index=rng)
-
-
-def simple_period_range_series(start, end, freq='D'):
-    """
-    Series with period range index and random data for test purposes.
-    """
-    rng = period_range(start, end, freq=freq)
-    return Series(np.random.randn(len(rng)), index=rng)
-
 
 class Base(object):
     """
@@ -137,64 +109,59 @@ def test_raises_on_non_datetimelike_index(self):
         xp = DataFrame()
         pytest.raises(TypeError, lambda: xp.resample('A').mean())
 
-    def test_resample_empty_series(self):
+    @pytest.mark.parametrize('freq', ['M', 'D', 'H'])
+    def test_resample_empty_series(self, freq, resample_method):
         # GH12771 & GH12868
 
+        if resample_method == 'ohlc':
+            pytest.skip('need to test for ohlc from GH13083')
+
         s = self.create_series()[:0]
+        result = getattr(s.resample(freq), resample_method)()
 
-        for freq in ['M', 'D', 'H']:
-            # need to test for ohlc from GH13083
-            methods = [method for method in resample_methods
-                       if method != 'ohlc']
-            for method in methods:
-                result = getattr(s.resample(freq), method)()
-
-                expected = s.copy()
-                expected.index = s.index._shallow_copy(freq=freq)
-                assert_index_equal(result.index, expected.index)
-                assert result.index.freq == expected.index.freq
-                assert_series_equal(result, expected, check_dtype=False)
-
-    def test_resample_empty_dataframe(self):
+        expected = s.copy()
+        expected.index = s.index._shallow_copy(freq=freq)
+        assert_index_equal(result.index, expected.index)
+        assert result.index.freq == expected.index.freq
+        assert_series_equal(result, expected, check_dtype=False)
+
+    @pytest.mark.parametrize('freq', ['M', 'D', 'H'])
+    def test_resample_empty_dataframe(self, freq, resample_method):
         # GH13212
         index = self.create_series().index[:0]
         f = DataFrame(index=index)
 
-        for freq in ['M', 'D', 'H']:
-            # count retains dimensions too
-            methods = downsample_methods + upsample_methods
-            for method in methods:
-                result = getattr(f.resample(freq), method)()
-                if method != 'size':
-                    expected = f.copy()
-                else:
-                    # GH14962
-                    expected = Series([])
-
-                expected.index = f.index._shallow_copy(freq=freq)
-                assert_index_equal(result.index, expected.index)
-                assert result.index.freq == expected.index.freq
-                assert_almost_equal(result, expected, check_dtype=False)
-
-            # test size for GH13212 (currently stays as df)
+        # count retains dimensions too
+        result = getattr(f.resample(freq), resample_method)()
+        if resample_method != 'size':
+            expected = f.copy()
+        else:
+            # GH14962
+            expected = Series([])
+
+        expected.index = f.index._shallow_copy(freq=freq)
+        assert_index_equal(result.index, expected.index)
+        assert result.index.freq == expected.index.freq
+        assert_almost_equal(result, expected, check_dtype=False)
+
+        # test size for GH13212 (currently stays as df)
 
     @pytest.mark.parametrize("index", tm.all_timeseries_index_generator(0))
     @pytest.mark.parametrize(
         "dtype",
         [np.float, np.int, np.object, 'datetime64[ns]'])
-    def test_resample_empty_dtypes(self, index, dtype):
+    def test_resample_empty_dtypes(self, index, dtype, resample_method):
 
         # Empty series were sometimes causing a segfault (for the functions
         # with Cython bounds-checking disabled) or an IndexError.  We just run
         # them to ensure they no longer do.  (GH #10228)
-        for how in downsample_methods + upsample_methods:
-            empty_series = Series([], index, dtype)
-            try:
-                getattr(empty_series.resample('d'), how)()
-            except DataError:
-                # Ignore these since some combinations are invalid
-                # (ex: doing mean with dtype of np.object)
-                pass
+        empty_series = Series([], index, dtype)
+        try:
+            getattr(empty_series.resample('d'), resample_method)()
+        except DataError:
+            # Ignore these since some combinations are invalid
+            # (ex: doing mean with dtype of np.object)
+            pass
 
     def test_resample_loffset_arg_type(self):
         # GH 13218, 15002

pandas/tests/resample/test_datetime_index.py

@@ -18,15 +18,13 @@
 from pandas.core.indexes.period import Period, period_range
 from pandas.core.indexes.timedeltas import timedelta_range
 from pandas.core.resample import DatetimeIndex, TimeGrouper
-from pandas.tests.resample.test_base import (
-    Base, business_day_offset, downsample_methods, simple_date_range_series,
-    simple_period_range_series)
+from pandas.tests.resample.test_base import Base
 import pandas.util.testing as tm
 from pandas.util.testing import (
     assert_almost_equal, assert_frame_equal, assert_series_equal)
 
 import pandas.tseries.offsets as offsets
-from pandas.tseries.offsets import Minute
+from pandas.tseries.offsets import BDay, Minute
 
 
 class TestDatetimeIndex(Base):
@@ -131,7 +129,7 @@ def test_resample_string_kwargs(self):
         with pytest.raises(ValueError):
             s.resample('5min', convention='starttt').mean()
 
-    def test_resample_how(self):
+    def test_resample_how(self, downsample_method):
         rng = date_range('1/1/2000 00:00:00', '1/1/2000 00:13:00', freq='min',
                          name='index')
         s = Series(np.random.randn(14), index=rng)
@@ -140,7 +138,7 @@ def test_resample_how(self):
         grouplist[1:6] = 1
         grouplist[6:11] = 2
         grouplist[11:] = 3
-        args = downsample_methods
+        arg = downsample_method
 
         def _ohlc(group):
             if isna(group).all():
@@ -149,29 +147,28 @@ def _ohlc(group):
 
         inds = date_range('1/1/2000', periods=4, freq='5min', name='index')
 
-        for arg in args:
+        if arg == 'ohlc':
+            func = _ohlc
+        else:
+            func = arg
+        try:
+            result = getattr(s.resample(
+                '5min', closed='right', label='right'), arg)()
+
+            expected = s.groupby(grouplist).agg(func)
+            assert result.index.name == 'index'
             if arg == 'ohlc':
-                func = _ohlc
+                expected = DataFrame(expected.values.tolist())
+                expected.columns = ['open', 'high', 'low', 'close']
+                expected.index = Index(inds, name='index')
+                assert_frame_equal(result, expected)
             else:
-                func = arg
-            try:
-                result = getattr(s.resample(
-                    '5min', closed='right', label='right'), arg)()
-
-                expected = s.groupby(grouplist).agg(func)
-                assert result.index.name == 'index'
-                if arg == 'ohlc':
-                    expected = DataFrame(expected.values.tolist())
-                    expected.columns = ['open', 'high', 'low', 'close']
-                    expected.index = Index(inds, name='index')
-                    assert_frame_equal(result, expected)
-                else:
-                    expected.index = inds
-                    assert_series_equal(result, expected)
-            except BaseException as exc:
-
-                exc.args += ('how=%s' % arg,)
-                raise
+                expected.index = inds
+                assert_series_equal(result, expected)
+        except BaseException as exc:
+
+            exc.args += ('how=%s' % arg,)
+            raise
 
     def test_numpy_compat(self):
         # see gh-12811
@@ -432,6 +429,7 @@ def test_resample_loffset(self, loffset):
 
         # to weekly
         result = ser.resample('w-sun').last()
+        business_day_offset = BDay()
         expected = ser.resample('w-sun', loffset=-business_day_offset).last()
         assert result.index[0] - business_day_offset == expected.index[0]
 
@@ -628,7 +626,7 @@ def test_resample_reresample(self):
         assert isinstance(result.index.freq, offsets.DateOffset)
         assert result.index.freq == offsets.Hour(8)
 
-    def test_resample_timestamp_to_period(self):
+    def test_resample_timestamp_to_period(self, simple_date_range_series):
         ts = simple_date_range_series('1/1/1990', '1/1/2000')
 
         result = ts.resample('A-DEC', kind='period').mean()
@@ -945,7 +943,7 @@ def test_nanosecond_resample_error(self):
 
         assert_series_equal(result, exp)
 
-    def test_resample_anchored_intraday(self):
+    def test_resample_anchored_intraday(self, simple_date_range_series):
         # #1471, #1458
 
         rng = date_range('1/1/2012', '4/1/2012', freq='100min')
@@ -985,7 +983,7 @@ def test_resample_anchored_intraday(self):
         resampled = ts.resample('M').mean()
         assert len(resampled) == 1
 
-    def test_resample_anchored_monthstart(self):
+    def test_resample_anchored_monthstart(self, simple_date_range_series):
         ts = simple_date_range_series('1/1/2000', '12/31/2002')
 
         freqs = ['MS', 'BMS', 'QS-MAR', 'AS-DEC', 'AS-JUN']
@@ -1015,7 +1013,8 @@ def test_resample_anchored_multiday(self):
         result = s.resample('2200L', label='right').mean()
         assert result.index[-1] == Timestamp('2014-10-15 23:00:04.200')
 
-    def test_corner_cases(self):
+    def test_corner_cases(self, simple_period_range_series,
+                          simple_date_range_series):
         # miscellaneous test coverage
 
         rng = date_range('1/1/2000', periods=12, freq='t')
@@ -1078,7 +1077,7 @@ def test_resample_median_bug_1688(self):
             exp = df.asfreq('T')
             tm.assert_frame_equal(result, exp)
 
-    def test_how_lambda_functions(self):
+    def test_how_lambda_functions(self, simple_date_range_series):
 
         ts = simple_date_range_series('1/1/2000', '4/1/2000')