MAINT: Complete Conversion to Pytest Idiom (#16201)

* MAINT: Convert test setup/teardown to pytest idiom

* tm.TestCase now just inherits from object
* setUpClass renamed to setup_class
* tearDownClass renamed to teardown_class
* setUp renamed to setup_method
* tearDown renamed to teardown_method

* MAINT: Remove unittest.TestCase from testing

* DOC: Update documentation for TestCase usage

tm.TestCase no longer follows the nosetest idiom,
so it is here to stay, so update the documentation
to say that we are using it still.

Closes gh-15990.

* TST: Patch Circle matplotlib failure

The tm.mplskip decorator was breaking on Circle,
so this commit removes the decorator and replaces it
with direct function calls to check for matplotlib.

* TST: Replace yield-based tests in test_query_eval

Author: gfyoung

doc/source/contributing.rst

@@ -632,14 +632,6 @@ framework that will facilitate testing and developing. Thus, instead of writing
     def test_really_cool_feature():
         ....
 
-Sometimes, it does make sense to bundle test functions together into a single class, either because the test file is testing multiple functions from a single module, and
-using test classes allows for better organization. However, instead of inheriting from ``tm.TestCase``, we should just inherit from ``object``:
-
-.. code-block:: python
-
-    class TestReallyCoolFeature(object):
-        ....
-
 Using ``pytest``
 ~~~~~~~~~~~~~~~~
 

pandas/tests/computation/test_eval.py

@@ -98,17 +98,17 @@ def _is_py3_complex_incompat(result, expected):
 class TestEvalNumexprPandas(tm.TestCase):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestEvalNumexprPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestEvalNumexprPandas, cls).setup_class()
         tm.skip_if_no_ne()
         import numexpr as ne
         cls.ne = ne
         cls.engine = 'numexpr'
         cls.parser = 'pandas'
 
     @classmethod
-    def tearDownClass(cls):
-        super(TestEvalNumexprPandas, cls).tearDownClass()
+    def teardown_class(cls):
+        super(TestEvalNumexprPandas, cls).teardown_class()
         del cls.engine, cls.parser
         if hasattr(cls, 'ne'):
             del cls.ne
@@ -137,12 +137,12 @@ def setup_ops(self):
         self.arith_ops = _good_arith_ops
         self.unary_ops = '-', '~', 'not '
 
-    def setUp(self):
+    def setup_method(self, method):
         self.setup_ops()
         self.setup_data()
         self.current_engines = filter(lambda x: x != self.engine, _engines)
 
-    def tearDown(self):
+    def teardown_method(self, method):
         del self.lhses, self.rhses, self.scalar_rhses, self.scalar_lhses
         del self.pandas_rhses, self.pandas_lhses, self.current_engines
 
@@ -723,8 +723,8 @@ def test_float_truncation(self):
 class TestEvalNumexprPython(TestEvalNumexprPandas):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestEvalNumexprPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestEvalNumexprPython, cls).setup_class()
         tm.skip_if_no_ne()
         import numexpr as ne
         cls.ne = ne
@@ -750,8 +750,8 @@ def check_chained_cmp_op(self, lhs, cmp1, mid, cmp2, rhs):
 class TestEvalPythonPython(TestEvalNumexprPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestEvalPythonPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestEvalPythonPython, cls).setup_class()
         cls.engine = 'python'
         cls.parser = 'python'
 
@@ -780,8 +780,8 @@ def check_alignment(self, result, nlhs, ghs, op):
 class TestEvalPythonPandas(TestEvalPythonPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestEvalPythonPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestEvalPythonPandas, cls).setup_class()
         cls.engine = 'python'
         cls.parser = 'pandas'
 
@@ -1070,16 +1070,16 @@ def test_performance_warning_for_poor_alignment(self, engine, parser):
 class TestOperationsNumExprPandas(tm.TestCase):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestOperationsNumExprPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestOperationsNumExprPandas, cls).setup_class()
         tm.skip_if_no_ne()
         cls.engine = 'numexpr'
         cls.parser = 'pandas'
         cls.arith_ops = expr._arith_ops_syms + expr._cmp_ops_syms
 
     @classmethod
-    def tearDownClass(cls):
-        super(TestOperationsNumExprPandas, cls).tearDownClass()
+    def teardown_class(cls):
+        super(TestOperationsNumExprPandas, cls).teardown_class()
         del cls.engine, cls.parser
 
     def eval(self, *args, **kwargs):
@@ -1492,8 +1492,8 @@ def test_simple_in_ops(self):
 class TestOperationsNumExprPython(TestOperationsNumExprPandas):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestOperationsNumExprPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestOperationsNumExprPython, cls).setup_class()
         cls.engine = 'numexpr'
         cls.parser = 'python'
         tm.skip_if_no_ne(cls.engine)
@@ -1566,8 +1566,8 @@ def test_simple_bool_ops(self):
 class TestOperationsPythonPython(TestOperationsNumExprPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestOperationsPythonPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestOperationsPythonPython, cls).setup_class()
         cls.engine = cls.parser = 'python'
         cls.arith_ops = expr._arith_ops_syms + expr._cmp_ops_syms
         cls.arith_ops = filter(lambda x: x not in ('in', 'not in'),
@@ -1577,8 +1577,8 @@ def setUpClass(cls):
 class TestOperationsPythonPandas(TestOperationsNumExprPandas):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestOperationsPythonPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestOperationsPythonPandas, cls).setup_class()
         cls.engine = 'python'
         cls.parser = 'pandas'
         cls.arith_ops = expr._arith_ops_syms + expr._cmp_ops_syms
@@ -1587,16 +1587,16 @@ def setUpClass(cls):
 class TestMathPythonPython(tm.TestCase):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestMathPythonPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestMathPythonPython, cls).setup_class()
         tm.skip_if_no_ne()
         cls.engine = 'python'
         cls.parser = 'pandas'
         cls.unary_fns = _unary_math_ops
         cls.binary_fns = _binary_math_ops
 
     @classmethod
-    def tearDownClass(cls):
+    def teardown_class(cls):
         del cls.engine, cls.parser
 
     def eval(self, *args, **kwargs):
@@ -1694,26 +1694,26 @@ def test_keyword_arg(self):
 class TestMathPythonPandas(TestMathPythonPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestMathPythonPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestMathPythonPandas, cls).setup_class()
         cls.engine = 'python'
         cls.parser = 'pandas'
 
 
 class TestMathNumExprPandas(TestMathPythonPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestMathNumExprPandas, cls).setUpClass()
+    def setup_class(cls):
+        super(TestMathNumExprPandas, cls).setup_class()
         cls.engine = 'numexpr'
         cls.parser = 'pandas'
 
 
 class TestMathNumExprPython(TestMathPythonPython):
 
     @classmethod
-    def setUpClass(cls):
-        super(TestMathNumExprPython, cls).setUpClass()
+    def setup_class(cls):
+        super(TestMathNumExprPython, cls).setup_class()
         cls.engine = 'numexpr'
         cls.parser = 'python'
 

pandas/tests/frame/test_asof.py

@@ -10,7 +10,7 @@
 
 
 class TestFrameAsof(TestData, tm.TestCase):
-    def setUp(self):
+    def setup_method(self, method):
         self.N = N = 50
         self.rng = date_range('1/1/1990', periods=N, freq='53s')
         self.df = DataFrame({'A': np.arange(N), 'B': np.arange(N)},

pandas/tests/frame/test_indexing.py

@@ -2914,7 +2914,7 @@ def test_type_error_multiindex(self):
 
 class TestDataFrameIndexingDatetimeWithTZ(tm.TestCase, TestData):
 
-    def setUp(self):
+    def setup_method(self, method):
         self.idx = Index(date_range('20130101', periods=3, tz='US/Eastern'),
                          name='foo')
         self.dr = date_range('20130110', periods=3)
@@ -2972,7 +2972,7 @@ def test_transpose(self):
 
 class TestDataFrameIndexingUInt64(tm.TestCase, TestData):
 
-    def setUp(self):
+    def setup_method(self, method):
         self.ir = Index(np.arange(3), dtype=np.uint64)
         self.idx = Index([2**63, 2**63 + 5, 2**63 + 10], name='foo')
 

pandas/tests/frame/test_period.py

@@ -14,7 +14,7 @@ def _permute(obj):
 
 class TestPeriodIndex(tm.TestCase):
 
-    def setUp(self):
+    def setup_method(self, method):
         pass
 
     def test_as_frame_columns(self):