Collapse functions and remove try except blocks

pandas/tests/groupby/aggregate/test_aggregate.py

@@ -133,32 +133,30 @@ def test_agg_python_multiindex(self):
         [lambda x: x.month, lambda x: x.weekday()],
     ])
     def test_aggregate_str_func(self, groupbyfunc):
-        def _check_results(grouped):
-            # single series
-            result = grouped['A'].agg('std')
-            expected = grouped['A'].std()
-            tm.assert_series_equal(result, expected)
-
-            # group frame by function name
-            result = grouped.aggregate('var')
-            expected = grouped.var()
-            tm.assert_frame_equal(result, expected)
-
-            # group frame by function dict
-            result = grouped.agg(OrderedDict([['A', 'var'],
-                                              ['B', 'std'],
-                                              ['C', 'mean'],
-                                              ['D', 'sem']]))
-            expected = DataFrame(OrderedDict([['A', grouped['A'].var()],
-                                              ['B', grouped['B'].std()],
-                                              ['C', grouped['C'].mean()],
-                                              ['D', grouped['D'].sem()]]))
-            tm.assert_frame_equal(result, expected)
-
-        _check_results(self.tsframe.groupby(groupbyfunc))
+        grouped = self.tsframe.groupby(groupbyfunc)
 
-    def test_aggregate_item_by_item(self):
+        # single series
+        result = grouped['A'].agg('std')
+        expected = grouped['A'].std()
+        tm.assert_series_equal(result, expected)
+
+        # group frame by function name
+        result = grouped.aggregate('var')
+        expected = grouped.var()
+        tm.assert_frame_equal(result, expected)
+
+        # group frame by function dict
+        result = grouped.agg(OrderedDict([['A', 'var'],
+                                          ['B', 'std'],
+                                          ['C', 'mean'],
+                                          ['D', 'sem']]))
+        expected = DataFrame(OrderedDict([['A', grouped['A'].var()],
+                                          ['B', grouped['B'].std()],
+                                          ['C', grouped['C'].mean()],
+                                          ['D', grouped['D'].sem()]]))
+        tm.assert_frame_equal(result, expected)
 
+    def test_aggregate_item_by_item(self):
         df = self.df.copy()
         df['E'] = ['a'] * len(self.df)
         grouped = self.df.groupby('A')
@@ -210,7 +208,6 @@ def test_agg_multiple_functions_maintain_order(self):
 
     def test_multiple_functions_tuples_and_non_tuples(self):
         # #1359
-
         funcs = [('foo', 'mean'), 'std']
         ex_funcs = [('foo', 'mean'), ('std', 'std')]
 
@@ -231,7 +228,6 @@ def test_agg_multiple_functions_too_many_lambdas(self):
             grouped.agg(funcs)
 
     def test_more_flexible_frame_multi_function(self):
-
         grouped = self.df.groupby('A')
 
         exmean = grouped.agg(OrderedDict([['C', np.mean], ['D', np.mean]]))

pandas/tests/groupby/aggregate/test_cython.py

@@ -17,7 +17,7 @@
 import pandas.util.testing as tm
 
 
-@pytest.mark.parametrize('op', [
+@pytest.mark.parametrize('op_name', [
     'count',
     'sum',
     'std',
@@ -29,41 +29,37 @@
     'min',
     'max',
 ])
-def test_cythonized_aggers(op):
+def test_cythonized_aggers(op_name):
     data = {'A': [0, 0, 0, 0, 1, 1, 1, 1, 1, 1., nan, nan],
             'B': ['A', 'B'] * 6,
             'C': np.random.randn(12)}
     df = DataFrame(data)
     df.loc[2:10:2, 'C'] = nan
 
-    def _testit(name):
+    op = lambda x: getattr(x, op_name)()
 
-        op = lambda x: getattr(x, name)()
+    # single column
+    grouped = df.drop(['B'], axis=1).groupby('A')
+    exp = {}
+    for cat, group in grouped:
+        exp[cat] = op(group['C'])
+    exp = DataFrame({'C': exp})
+    exp.index.name = 'A'
+    result = op(grouped)
+    tm.assert_frame_equal(result, exp)
 
-        # single column
-        grouped = df.drop(['B'], axis=1).groupby('A')
-        exp = {}
-        for cat, group in grouped:
-            exp[cat] = op(group['C'])
-        exp = DataFrame({'C': exp})
-        exp.index.name = 'A'
-        result = op(grouped)
-        tm.assert_frame_equal(result, exp)
+    # multiple columns
+    grouped = df.groupby(['A', 'B'])
+    expd = {}
+    for (cat1, cat2), group in grouped:
+        expd.setdefault(cat1, {})[cat2] = op(group['C'])
+    exp = DataFrame(expd).T.stack(dropna=False)
+    exp.index.names = ['A', 'B']
+    exp.name = 'C'
 
-        # multiple columns
-        grouped = df.groupby(['A', 'B'])
-        expd = {}
-        for (cat1, cat2), group in grouped:
-            expd.setdefault(cat1, {})[cat2] = op(group['C'])
-        exp = DataFrame(expd).T.stack(dropna=False)
-        exp.index.names = ['A', 'B']
-        exp.name = 'C'
-
-        result = op(grouped)['C']
-        if name in ['sum', 'prod']:
-            tm.assert_series_equal(result, exp)
-
-    _testit(op)
+    result = op(grouped)['C']
+    if op_name in ['sum', 'prod']:
+        tm.assert_series_equal(result, exp)
 
 
 def test_cython_agg_boolean():
@@ -151,11 +147,7 @@ def test__cython_agg_general(op, targop):
 
     result = df.groupby(labels)._cython_agg_general(op)
     expected = df.groupby(labels).agg(targop)
-    try:
-        tm.assert_frame_equal(result, expected)
-    except BaseException as exc:
-        exc.args += ('operation: %s' % op, )
-        raise
+    tm.assert_frame_equal(result, expected)
 
 
 @pytest.mark.parametrize('op, targop', [
@@ -173,11 +165,7 @@ def test_cython_agg_empty_buckets(op, targop):
     # which sets different values for min_count, so do that here.
     result = df.groupby(pd.cut(df[0], grps))._cython_agg_general(op)
     expected = df.groupby(pd.cut(df[0], grps)).agg(lambda x: targop(x))
-    try:
-        tm.assert_frame_equal(result, expected)
-    except BaseException as exc:
-        exc.args += ('operation: %s' % op,)
-        raise
+    tm.assert_frame_equal(result, expected)
 
 
 def test_cython_agg_empty_buckets_nanops():

pandas/tests/groupby/aggregate/test_other.py

@@ -158,7 +158,6 @@ def test_aggregate_api_consistency():
     # GH 9052
     # make sure that the aggregates via dict
     # are consistent
-
     df = DataFrame({'A': ['foo', 'bar', 'foo', 'bar',
                           'foo', 'bar', 'foo', 'foo'],
                     'B': ['one', 'one', 'two', 'two',
@@ -230,7 +229,6 @@ def test_agg_dict_renaming_deprecation():
 
 def test_agg_compat():
     # GH 12334
-
     df = DataFrame({'A': ['foo', 'bar', 'foo', 'bar',
                           'foo', 'bar', 'foo', 'foo'],
                     'B': ['one', 'one', 'two', 'two',
@@ -257,7 +255,6 @@ def test_agg_compat():
 
 def test_agg_nested_dicts():
     # API change for disallowing these types of nested dicts
-
     df = DataFrame({'A': ['foo', 'bar', 'foo', 'bar',
                           'foo', 'bar', 'foo', 'foo'],
                     'B': ['one', 'one', 'two', 'two',
@@ -341,7 +338,6 @@ def bad(x):
 def test_agg_consistency():
     # agg with ([]) and () not consistent
     # GH 6715
-
     def P1(a):
         try:
             return np.percentile(a.dropna(), q=1)
@@ -435,7 +431,6 @@ def test_agg_timezone_round_trip():
 
 def test_sum_uint64_overflow():
     # see gh-14758
-
     # Convert to uint64 and don't overflow
     df = pd.DataFrame([[1, 2], [3, 4], [5, 6]], dtype=object)
     df = df + 9223372036854775807
@@ -492,7 +487,7 @@ def test_agg_structs_series(structure, expected):
 
 
 @pytest.mark.xfail(reason="GH-18869: agg func not called on empty groups.")
-def test_agg_category_nansum(self):
+def test_agg_category_nansum():
     categories = ['a', 'b', 'c']
     df = pd.DataFrame({"A": pd.Categorical(['a', 'a', 'b'],
                                            categories=categories),