ENH: test can_cast(complex dtypes)

Author: ev-br

Diff for: array_api_tests/test_data_type_functions.py

@@ -19,10 +19,18 @@ def non_complex_dtypes():
     return xps.boolean_dtypes() | hh.real_dtypes
 
 
+def numeric_dtypes():
+    return xps.boolean_dtypes() | hh.real_dtypes | hh.complex_dtypes
+
+
 def float32(n: Union[int, float]) -> float:
     return struct.unpack("!f", struct.pack("!f", float(n)))[0]
 
 
+def _float_match_complex(complex_dtype):
+    return xp.float32 if complex_dtype == xp.complex64 else xp.float64
+
+
 @given(
     x_dtype=non_complex_dtypes(),
     dtype=non_complex_dtypes(),
@@ -107,7 +115,7 @@ def test_broadcast_to(x, data):
     # TODO: test values
 
 
-@given(_from=non_complex_dtypes(), to=non_complex_dtypes(), data=st.data())
+@given(_from=numeric_dtypes(), to=numeric_dtypes(), data=st.data())
 def test_can_cast(_from, to, data):
     from_ = data.draw(
         st.just(_from) | hh.arrays(dtype=_from, shape=hh.shapes()), label="from_"
@@ -127,8 +135,15 @@ def test_can_cast(_from, to, data):
                 break
         assert same_family is not None  # sanity check
         if same_family:
-            from_min, from_max = dh.dtype_ranges[_from]
-            to_min, to_max = dh.dtype_ranges[to]
+            from_dtype = (_float_match_complex(_from)
+                          if _from in (xp.complex64, xp.complex128)
+                          else _from)
+            to_dtype = (_float_match_complex(to)
+                        if to in (xp.complex64, xp.complex128)
+                        else to)
+
+            from_min, from_max = dh.dtype_ranges[from_dtype]
+            to_min, to_max = dh.dtype_ranges[to_dtype]
             expected = from_min >= to_min and from_max <= to_max
         else:
             expected = False
@@ -139,6 +154,7 @@ def test_can_cast(_from, to, data):
         assert out == expected, f"{out=}, but should be {expected} {f_func}"
 
 
+
 @pytest.mark.parametrize("dtype", dh.real_float_dtypes)
 def test_finfo(dtype):
     out = xp.finfo(dtype)