feat: update NumPy type to Mat type fail message

Output string representation of NumPy array type if it is not
convertible to OpenCV Mat type

modules/python/test/test_misc.py

@@ -219,6 +219,14 @@ class Arguments(NewOpenCVTests):
         #res6 = cv.utils.dumpInputArray([a, b])
         #self.assertEqual(res6, "InputArrayOfArrays: empty()=false kind=0x00050000 flags=0x01050000 total(-1)=2 dims(-1)=1 size(-1)=2x1 type(0)=CV_32FC1 dims(0)=4 size(0)=[2 3 4 5]")
 
+    def test_unsupported_numpy_data_types_string_description(self):
+        for dtype in (object, str, np.complex128):
+            test_array = np.zeros((4, 4, 3), dtype=dtype)
+            msg = ".*type = {} is not supported".format(test_array.dtype)
+            self.assertRaisesRegex(
+                Exception, msg, cv.utils.dumpInputArray, test_array
+            )
+
     def test_20968(self):
         pixel = np.uint8([[[40, 50, 200]]])
         _ = cv.cvtColor(pixel, cv.COLOR_RGB2BGR)  # should not raise exception