Remove redundant set copy and sort another set.

snowfakery/generate_mapping_from_factory.py

@@ -30,7 +30,9 @@ def find_record_type_field(fields, context_name):
     if not record_type_fields:
         return None
     elif len(record_type_fields) > 1:
-        raise DataGenError(f"Only one RecordType field allowed: {context_name}")
+        raise DataGenError(
+            f"Only one RecordType field allowed: {context_name}", None, None
+        )
     elif record_type_fields[0].name != "RecordType":
         raise DataGenNameError(
             "Recordtype field needs this capitalization: RecordType", None, None
@@ -60,7 +62,7 @@ def generate_record_type_pseudo_tables(summary):
         record_type_pseudo_table.record_type = record_type_name
 
         # copy over the dependencies from the real table
-        for dependency in sorted(summary.intertable_dependencies.copy()):
+        for dependency in sorted(summary.intertable_dependencies):
             if dependency.table_name_from == real_table_name:
                 summary.intertable_dependencies.add(
                     Dependency(record_type_name, *dependency[1:])
@@ -100,7 +102,7 @@ def _table_is_free(table_name, dependencies, sorted_tables):
     usage examples.
     """
     tables_this_table_depends_upon = dependencies.get(table_name, {})
-    for dependency in tables_this_table_depends_upon.copy():
+    for dependency in sorted(tables_this_table_depends_upon):
         if dependency.table_name_to in sorted_tables:
             tables_this_table_depends_upon.remove(dependency)
 
@@ -151,9 +153,9 @@ def mappings_from_sorted_tables(
 
         if "RecordType" in table.fields:
             fielddef = table.fields["RecordType"].definition
-            if not getattr(fielddef, "definition"):
+            if not getattr(fielddef, "definition", None):
                 raise DataGenError(
-                    "Record type definitions must be simple, not computed"
+                    "Record type definitions must be simple, not computed", None, None
                 )
             record_type = fielddef.definition
             filters = [f"RecordType = '{record_type}'"]