TST: Add test for comparison functions

numpy/core/tests/test_umath.py

@@ -185,6 +185,82 @@ def __array_wrap__(self, arr, context):
 
 
 class TestComparisons:
+    @pytest.mark.parametrize('dtype', np.sctypes['uint'] + np.sctypes['int'] +
+                             np.sctypes['float'] + [np.bool_])
+    def test_comparison_functions(self, dtype):
+        # Initialize input arrays
+        if dtype == np.bool_:
+            a = np.random.choice(a=[False, True], size=1000)
+            b = np.random.choice(a=[False, True], size=1000)
+            scalar = True
+        else:
+            a = np.random.randint(low=1, high=10, size=1000).astype(dtype)
+            b = np.random.randint(low=1, high=10, size=1000).astype(dtype)
+            scalar = 5
+        scalar_np = np.dtype(dtype).type(scalar)
+        a_lst = a.tolist()
+        b_lst = b.tolist()
+
+        # (Binary) Comparison (x1=array, x2=array)
+        lt_b = np.less(a, b)
+        le_b = np.less_equal(a, b)
+        gt_b = np.greater(a, b)
+        ge_b = np.greater_equal(a, b)
+        eq_b = np.equal(a, b)
+        ne_b = np.not_equal(a, b)
+        lt_b_lst = [x < y for x, y in zip(a_lst, b_lst)]
+        le_b_lst = [x <= y for x, y in zip(a_lst, b_lst)]
+        gt_b_lst = [x > y for x, y in zip(a_lst, b_lst)]
+        ge_b_lst = [x >= y for x, y in zip(a_lst, b_lst)]
+        eq_b_lst = [x == y for x, y in zip(a_lst, b_lst)]
+        ne_b_lst = [x != y for x, y in zip(a_lst, b_lst)]
+
+        # (Scalar1) Comparison (x1=scalar, x2=array)
+        lt_s1 = np.less(scalar_np, b)
+        le_s1 = np.less_equal(scalar_np, b)
+        gt_s1 = np.greater(scalar_np, b)
+        ge_s1 = np.greater_equal(scalar_np, b)
+        eq_s1 = np.equal(scalar_np, b)
+        ne_s1 = np.not_equal(scalar_np, b)
+        lt_s1_lst = [scalar < x for x in b_lst]
+        le_s1_lst = [scalar <= x for x in b_lst]
+        gt_s1_lst = [scalar > x for x in b_lst]
+        ge_s1_lst = [scalar >= x for x in b_lst]
+        eq_s1_lst = [scalar == x for x in b_lst]
+        ne_s1_lst = [scalar != x for x in b_lst]
+
+        # (Scalar2) Comparison (x1=array, x2=scalar)
+        lt_s2 = np.less(a, scalar_np)
+        le_s2 = np.less_equal(a, scalar_np)
+        gt_s2 = np.greater(a, scalar_np)
+        ge_s2 = np.greater_equal(a, scalar_np)
+        eq_s2 = np.equal(a, scalar_np)
+        ne_s2 = np.not_equal(a, scalar_np)
+        lt_s2_lst = [x < scalar for x in a_lst]
+        le_s2_lst = [x <= scalar for x in a_lst]
+        gt_s2_lst = [x > scalar for x in a_lst]
+        ge_s2_lst = [x >= scalar for x in a_lst]
+        eq_s2_lst = [x == scalar for x in a_lst]
+        ne_s2_lst = [x != scalar for x in a_lst]
+
+        # Compare comparison functions (Python vs NumPy) using native Python
+        def compare(lt, le, gt, ge, eq, ne, lt_lst, le_lst, gt_lst, ge_lst,
+                    eq_lst, ne_lst):
+            assert_(lt.tolist() == lt_lst, "Comparison function check (lt)")
+            assert_(le.tolist() == le_lst, "Comparison function check (le)")
+            assert_(gt.tolist() == gt_lst, "Comparison function check (gt)")
+            assert_(ge.tolist() == ge_lst, "Comparison function check (ge)")
+            assert_(eq.tolist() == eq_lst, "Comparison function check (eq)")
+            assert_(ne.tolist() == ne_lst, "Comparison function check (ne)")
+
+        # Sequence: Binary, Scalar1 and Scalar2
+        compare(lt_b, le_b, gt_b, ge_b, eq_b, ne_b, lt_b_lst, le_b_lst,
+                gt_b_lst, ge_b_lst, eq_b_lst, ne_b_lst)
+        compare(lt_s1, le_s1, gt_s1, ge_s1, eq_s1, ne_s1, lt_s1_lst, le_s1_lst,
+                gt_s1_lst, ge_s1_lst, eq_s1_lst, ne_s1_lst)
+        compare(lt_s2, le_s2, gt_s2, ge_s2, eq_s2, ne_s2, lt_s2_lst, le_s2_lst,
+                gt_s2_lst, ge_s2_lst, eq_s2_lst, ne_s2_lst)
+
     def test_ignore_object_identity_in_equal(self):
         # Check comparing identical objects whose comparison
         # is not a simple boolean, e.g., arrays that are compared elementwise.