refactor: allow 0 as missing values

component/widget/reclassify/reclassify_view.py

@@ -206,13 +206,15 @@ def load_matrix_content(self, *_):
         # check that the destination values are all available
         widget = list(self.reclassify_table.class_select_list.values())[0]
         classes = [i["value"] for i in widget.items]
-        if not all(v in classes for v in input_data.to_code.unique()):
-            # get the missing values
-            missing_values = ",".join(
-                [str(v) for v in input_data.to_code.unique() if v not in classes]
-            )
+
+        # get the missing values
+        missing_values = [v for v in input_data.to_code.unique() if v not in classes]
+
+        # if missing values are only 0, we can pass
+        if missing_values and not (len(missing_values) == 1 and missing_values[0] == 0):
+            missing_values_str = ",".join(map(str, missing_values))
             raise Exception(
-                f"Some of the target land cover classes ({missing_values}) are not present in the destination land cover classes."
+                f"Some of the target land cover classes ({missing_values_str}) are not present in the destination land cover classes."
             )
 
         # fill the data