Fix pytest catchwarnings bugs on Python2.7 ???

Author: kernc

pandas/tests/sparse/frame/test_frame.py

@@ -458,7 +458,6 @@ def test_iloc(self):
                               iframe.iloc[:, 0].sp_index)
 
     def test_set_value(self):
-
         # ok, as the index gets converted to object
         frame = self.frame.copy()
         with tm.assert_produces_warning((FutureWarning,
@@ -593,8 +592,9 @@ def test_setitem_chained_no_consolidate(self):
         # issuecomment-361696418
         # chained setitem used to cause consolidation
         sdf = pd.SparseDataFrame([[np.nan, 1], [2, np.nan]])
-        with pd.option_context('mode.chained_assignment', None):
-            sdf[0][1] = 2
+        with tm.assert_produces_warning(PerformanceWarning):
+            with pd.option_context('mode.chained_assignment', None):
+                sdf[0][1] = 2
         assert len(sdf._data.blocks) == 2
 
     def test_delitem(self):
@@ -1333,24 +1333,32 @@ def spindex_kind(request):
 @pytest.mark.parametrize('indexer', ['iat'])
 @pytest.mark.parametrize('key', [(0, 0)])
 def test_frame_assignment_at(spindex_kind, indexer, key):
-    _test_assignment(spindex_kind, indexer, key)
+    with tm.assert_produces_warning(PerformanceWarning):
+        _test_assignment(spindex_kind, indexer, key)
 
 
 @pytest.mark.parametrize('indexer', ['at', 'loc', 'iloc'])
 @pytest.mark.parametrize('key', [0,
                                  [0, 1],
                                  [True, False]])
 def test_frame_assignment_loc(spindex_kind, indexer, key):
-    _test_assignment(spindex_kind, indexer, key)
+    with tm.assert_produces_warning(PerformanceWarning):
+        _test_assignment(spindex_kind, indexer, key)
 
 
 @pytest.mark.parametrize('key', [None,
                                  [True, False]])
 def test_frame_assignment_setitem(spindex_kind, key):
-    _test_assignment(spindex_kind, None, key)
+    with tm.assert_produces_warning(PerformanceWarning):
+        _test_assignment(spindex_kind, None, key)
+
+
+@pytest.mark.parametrize('key', [3])
+def test_frame_assignment_extend_index_loc(spindex_kind, key):
+    _test_assignment(spindex_kind, 'loc', key)
 
 
-@pytest.mark.parametrize('indexer', ['loc', 'at'])
 @pytest.mark.parametrize('key', [3])
-def test_frame_assignment_extend_index(spindex_kind, indexer, key):
-    _test_assignment(spindex_kind, indexer, key)
+def test_frame_assignment_extend_index_at(spindex_kind, key):
+    with tm.assert_produces_warning(PerformanceWarning):
+        _test_assignment(spindex_kind, 'at', key)

pandas/tests/sparse/test_format.py

@@ -8,7 +8,7 @@
 from pandas.compat import (is_platform_windows,
                            is_platform_32bit)
 from pandas.core.config import option_context
-
+from pandas.errors import PerformanceWarning
 
 use_32bit_repr = is_platform_windows() or is_platform_32bit()
 
@@ -124,9 +124,10 @@ def test_sparse_repr_after_set(self):
         sdf = pd.SparseDataFrame([[np.nan, 1], [2, np.nan]])
         res = sdf.copy()
 
-        # Ignore the warning
-        with pd.option_context('mode.chained_assignment', None):
-            sdf[0][1] = 2  # This line triggers the bug
+        with tm.assert_produces_warning(PerformanceWarning):
+            # Ignore the warning
+            with pd.option_context('mode.chained_assignment', None):
+                sdf[0][1] = 2  # This line triggers the bug
 
         repr(sdf)
         tm.assert_sp_frame_equal(sdf, res)