[mypyc] feat: make frozenset literal compilation deterministic [1/1]

mypyc/codegen/literals.py

@@ -141,7 +141,22 @@ def encoded_tuple_values(self) -> list[str]:
         return self._encode_collection_values(self.tuple_literals)
 
     def encoded_frozenset_values(self) -> list[str]:
-        return self._encode_collection_values(self.frozenset_literals)
+        def sort_frozenset_recursive(value: frozenset[object]) -> list[object]:
+            # even though frozensets are not sorted in python, we need to sort the items here
+            # to improve the determinism of the generated C file, making it easier to compare
+            # differences in the C files generated by different versions of your code.
+            sort_helper = {repr(v) + type(v).__name__: v for v in value}
+            items = []
+            for key in sorted(sort_helper):
+                v = sort_helper[key]
+                if isinstance(v, frozenset):
+                    v = sort_frozenset_recursive(v)
+                items.append(v)
+            return items
+
+        return self._encode_collection_values(
+            {sort_frozenset_recursive(fr): i for fr, i in self.frozenset_literals.items()}
+        )
 
     def _encode_collection_values(
         self, values: dict[tuple[object, ...], int] | dict[frozenset[object], int]