Fixed/Enhanced union_types function

This patch fixes union_types output in case of using
typedefs which uses union within with another typedefs/unions

libyang/schema.py

@@ -555,16 +555,27 @@ def typedef(self) -> "Typedef":
                 return import_module.get_typedef(type_name)
         return None
 
-    def union_types(self) -> Iterator["Type"]:
+    def union_types(self, with_typedefs: bool = False) -> Iterator["Type"]:
         if self.cdata.basetype != self.UNION:
             return
 
+        typedef = self.typedef()
         t = ffi.cast("struct lysc_type_union *", self.cdata)
         if self.cdata_parsed and self.cdata_parsed.types != ffi.NULL:
             for union_type, union_type_parsed in zip(
                 ly_array_iter(t.types), ly_array_iter(self.cdata_parsed.types)
             ):
                 yield Type(self.context, union_type, union_type_parsed)
+        elif (
+            with_typedefs
+            and typedef
+            and typedef.cdata
+            and typedef.cdata.type.types != ffi.NULL
+        ):
+            for union_type, union_type_parsed in zip(
+                ly_array_iter(t.types), ly_array_iter(typedef.cdata.type.types)
+            ):
+                yield Type(self.context, union_type, union_type_parsed)
         else:
             for union_type in ly_array_iter(t.types):
                 yield Type(self.context, union_type, None)

tests/test_schema.py

@@ -415,7 +415,9 @@ def test_leaf_type_union(self):
         self.assertEqual(t.name(), "types:number")
         self.assertEqual(t.base(), Type.UNION)
         types = set(u.name() for u in t.union_types())
+        types2 = set(u.name() for u in t.union_types(with_typedefs=True))
         self.assertEqual(types, set(["int16", "int32", "uint16", "uint32"]))
+        self.assertEqual(types2, set(["signed", "unsigned"]))
         for u in t.union_types():
             ext = u.get_extension(
                 "type-desc", prefix="omg-extensions", arg_value=f"<{u.name()}>"