TST/REF: fixturize TestEval (#44663)

Author: jbrockmendel

pandas/tests/computation/test_eval.py

@@ -53,11 +53,14 @@
     params=(
         pytest.param(
             engine,
-            marks=pytest.mark.skipif(
-                engine == "numexpr" and not USE_NUMEXPR,
-                reason=f"numexpr enabled->{USE_NUMEXPR}, "
-                f"installed->{NUMEXPR_INSTALLED}",
-            ),
+            marks=[
+                pytest.mark.skipif(
+                    engine == "numexpr" and not USE_NUMEXPR,
+                    reason=f"numexpr enabled->{USE_NUMEXPR}, "
+                    f"installed->{NUMEXPR_INSTALLED}",
+                ),
+                td.skip_if_no_ne,
+            ],
         )
         for engine in ENGINES
     )
@@ -145,10 +148,12 @@ def lhs(request):
 midhs = lhs
 
 
-@td.skip_if_no_ne
-class TestEvalNumexprPandas:
-    engine = "numexpr"
-    parser = "pandas"
+class TestEval:
+    @pytest.fixture(autouse=True)
+    def set_engine_parser_attrs(self, engine, parser):
+        # Older tests look for these as attributes, so we set them here.
+        self.engine = engine
+        self.parser = parser
 
     @classmethod
     def setup_class(cls):
@@ -184,47 +189,18 @@ def test_complex_cmp_ops(self, cmp1, cmp2, binop, lhs, rhs):
         self.check_equal(result, expected)
 
     @pytest.mark.parametrize("cmp_op", expr.CMP_OPS_SYMS)
-    def test_simple_cmp_ops(self, cmp_op):
-        bool_lhses = (
-            DataFrame(tm.randbool(size=(10, 5))),
-            Series(tm.randbool((5,))),
-            tm.randbool(),
-        )
-        bool_rhses = (
-            DataFrame(tm.randbool(size=(10, 5))),
-            Series(tm.randbool((5,))),
-            tm.randbool(),
-        )
+    def test_simple_cmp_ops(self, cmp_op, lhs, rhs):
+        lhs = lhs < 0
+        rhs = rhs < 0
 
         if self.parser == "python" and cmp_op in ["in", "not in"]:
             msg = "'(In|NotIn)' nodes are not implemented"
-            for lhs, rhs in product(bool_lhses, bool_rhses):
 
-                with pytest.raises(NotImplementedError, match=msg):
-                    self.check_simple_cmp_op(lhs, cmp_op, rhs)
+            with pytest.raises(NotImplementedError, match=msg):
+                self.check_simple_cmp_op(lhs, cmp_op, rhs)
             return
 
-        for lhs, rhs in product(bool_lhses, bool_rhses):
-            self.check_simple_cmp_op(lhs, cmp_op, rhs)
-
-    @pytest.mark.parametrize("op", _good_arith_ops)
-    def test_binary_arith_ops(self, op, lhs, rhs, request):
-        self.check_binary_arith_op(lhs, op, rhs)
-
-    def test_modulus(self, lhs, rhs):
-        self.check_modulus(lhs, "%", rhs)
-
-    def test_floor_division(self, lhs, rhs):
-        self.check_floor_division(lhs, "//", rhs)
-
-    @td.skip_if_windows
-    def test_pow(self, lhs, rhs):
-        # odd failure on win32 platform, so skip
-        self.check_pow(lhs, "**", rhs)
-
-    @pytest.mark.parametrize("op", expr.CMP_OPS_SYMS)
-    def test_single_invert_op(self, op, lhs):
-        self.check_single_invert_op(lhs, op)
+        self.check_simple_cmp_op(lhs, cmp_op, rhs)
 
     @pytest.mark.parametrize("op", expr.CMP_OPS_SYMS)
     def test_compound_invert_op(self, op, lhs, rhs, request):
@@ -266,11 +242,16 @@ def check_equal(self, result, expected):
             assert result == expected
 
     def check_chained_cmp_op(self, lhs, cmp1, mid, cmp2, rhs):
-        def check_operands(left, right, cmp_op):
-            return _eval_single_bin(left, cmp_op, right, self.engine)
 
-        lhs_new = check_operands(lhs, mid, cmp1)
-        rhs_new = check_operands(mid, rhs, cmp2)
+        if self.parser == "python":
+            ex1 = f"lhs {cmp1} mid {cmp2} rhs"
+            msg = "'BoolOp' nodes are not implemented"
+            with pytest.raises(NotImplementedError, match=msg):
+                pd.eval(ex1, engine=self.engine, parser=self.parser)
+            return
+
+        lhs_new = _eval_single_bin(lhs, cmp1, mid, self.engine)
+        rhs_new = _eval_single_bin(mid, cmp2, rhs, self.engine)
 
         if lhs_new is not None and rhs_new is not None:
             ex1 = f"lhs {cmp1} mid {cmp2} rhs"
@@ -306,7 +287,8 @@ def check_simple_cmp_op(self, lhs, cmp1, rhs):
             result = pd.eval(ex, engine=self.engine, parser=self.parser)
             self.check_equal(result, expected)
 
-    def check_binary_arith_op(self, lhs, arith1, rhs):
+    @pytest.mark.parametrize("arith1", _good_arith_ops)
+    def test_binary_arith_ops(self, arith1, lhs, rhs):
         ex = f"lhs {arith1} rhs"
         result = pd.eval(ex, engine=self.engine, parser=self.parser)
         expected = _eval_single_bin(lhs, arith1, rhs, self.engine)
@@ -339,20 +321,24 @@ def check_alignment(self, result, nlhs, ghs, op):
 
     # modulus, pow, and floor division require special casing
 
-    def check_modulus(self, lhs, arith1, rhs):
-        ex = f"lhs {arith1} rhs"
+    def test_modulus(self, lhs, rhs):
+        ex = r"lhs % rhs"
         result = pd.eval(ex, engine=self.engine, parser=self.parser)
         expected = lhs % rhs
-
         tm.assert_almost_equal(result, expected)
-        expected = self.ne.evaluate(f"expected {arith1} rhs")
-        if isinstance(result, (DataFrame, Series)):
-            tm.assert_almost_equal(result.values, expected)
+
+        if self.engine == "numexpr":
+            expected = self.ne.evaluate(r"expected % rhs")
+            if isinstance(result, (DataFrame, Series)):
+                tm.assert_almost_equal(result.values, expected)
+            else:
+                tm.assert_almost_equal(result, expected.item())
         else:
-            tm.assert_almost_equal(result, expected.item())
+            expected = _eval_single_bin(expected, "%", rhs, self.engine)
+            tm.assert_almost_equal(result, expected)
 
-    def check_floor_division(self, lhs, arith1, rhs):
-        ex = f"lhs {arith1} rhs"
+    def test_floor_division(self, lhs, rhs):
+        ex = "lhs // rhs"
 
         if self.engine == "python":
             res = pd.eval(ex, engine=self.engine, parser=self.parser)
@@ -371,8 +357,10 @@ def check_floor_division(self, lhs, arith1, rhs):
                     parser=self.parser,
                 )
 
-    def check_pow(self, lhs, arith1, rhs):
-        ex = f"lhs {arith1} rhs"
+    @td.skip_if_windows
+    def test_pow(self, lhs, rhs):
+        # odd failure on win32 platform, so skip
+        ex = "lhs ** rhs"
         expected = _eval_single_bin(lhs, "**", rhs, self.engine)
         result = pd.eval(ex, engine=self.engine, parser=self.parser)
 
@@ -387,19 +375,19 @@ def check_pow(self, lhs, arith1, rhs):
         else:
             tm.assert_almost_equal(result, expected)
 
-            ex = f"(lhs {arith1} rhs) {arith1} rhs"
+            ex = "(lhs ** rhs) ** rhs"
             result = pd.eval(ex, engine=self.engine, parser=self.parser)
 
             middle = _eval_single_bin(lhs, "**", rhs, self.engine)
             expected = _eval_single_bin(middle, "**", rhs, self.engine)
             tm.assert_almost_equal(result, expected)
 
-    def check_single_invert_op(self, elem, cmp1):
+    def check_single_invert_op(self, lhs):
         # simple
         try:
-            elb = elem.astype(bool)
+            elb = lhs.astype(bool)
         except AttributeError:
-            elb = np.array([bool(elem)])
+            elb = np.array([bool(lhs)])
         expected = ~elb
         result = pd.eval("~elb", engine=self.engine, parser=self.parser)
         tm.assert_almost_equal(expected, result)
@@ -766,43 +754,6 @@ def test_disallow_python_keywords(self):
             df.query("lambda == 0")
 
 
-@td.skip_if_no_ne
-class TestEvalNumexprPython(TestEvalNumexprPandas):
-    engine = "numexpr"
-    parser = "python"
-
-    def check_chained_cmp_op(self, lhs, cmp1, mid, cmp2, rhs):
-        ex1 = f"lhs {cmp1} mid {cmp2} rhs"
-        msg = "'BoolOp' nodes are not implemented"
-        with pytest.raises(NotImplementedError, match=msg):
-            pd.eval(ex1, engine=self.engine, parser=self.parser)
-
-
-class TestEvalPythonPython(TestEvalNumexprPython):
-    engine = "python"
-    parser = "python"
-
-    def check_modulus(self, lhs, arith1, rhs):
-        ex = f"lhs {arith1} rhs"
-        result = pd.eval(ex, engine=self.engine, parser=self.parser)
-
-        expected = lhs % rhs
-        tm.assert_almost_equal(result, expected)
-
-        expected = _eval_single_bin(expected, arith1, rhs, self.engine)
-        tm.assert_almost_equal(result, expected)
-
-
-class TestEvalPythonPandas(TestEvalPythonPython):
-    engine = "python"
-    parser = "pandas"
-
-    def check_chained_cmp_op(self, lhs, cmp1, mid, cmp2, rhs):
-        # FIXME: by calling this parent class method, we are using the parent
-        #  class's "engine" and "parser", which I don't think is what we want.
-        TestEvalNumexprPandas.check_chained_cmp_op(self, lhs, cmp1, mid, cmp2, rhs)
-
-
 f = lambda *args, **kwargs: np.random.randn()