fix, python: allow extending alias types (#4190)

generators/python/sdk/CHANGELOG.md

@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.3.3] - 2024-08-02
+
+- Fix: The generator now allows you to extend aliased types (as long as they're objects).
+
 ## [3.3.2] - 2024-08-02
 
 - Fix: regression in readme generation introduced in 3.3.1

generators/python/sdk/VERSION

@@ -1 +1 @@
-3.3.2
+3.3.3

generators/python/src/fern_python/generator_cli/readme_snippet_builder.py

@@ -117,7 +117,7 @@ def _build_timeout_snippets(self) -> List[str]:
 
                 client_instantiation = AST.ClassInstantiation(
                     class_=self._root_client.sync_client.class_reference,
-                    args=[AST.Expression("..."), AST.Expression('timeout=20.0')],
+                    args=[AST.Expression("..."), AST.Expression("timeout=20.0")],
                 )
 
                 def _client_writer(writer: AST.NodeWriter) -> None:

generators/python/src/fern_python/generators/context/pydantic_generator_context_impl.py

@@ -136,7 +136,16 @@ def get_filepath_for_type_id(self, type_id: ir_types.TypeId, as_request: bool) -
     def get_all_properties_including_extensions(self, type_name: ir_types.TypeId) -> List[ir_types.ObjectProperty]:
         declaration = self.get_declaration_for_type_id(type_name)
         shape = declaration.shape.get_as_union()
-        if shape.type != "object":
+
+        if shape.type == "alias":
+            resolved_type_union = shape.resolved_type.get_as_union()
+            if resolved_type_union.type != "named":
+                raise RuntimeError(
+                    f"Cannot get properties because {declaration.name.name.original_name} is not an object, it's a {shape.type}"
+                )
+            else:
+                return self.get_all_properties_including_extensions(resolved_type_union.name.type_id)
+        elif shape.type != "object":
             raise RuntimeError(
                 f"Cannot get properties because {declaration.name.name.original_name} is not an object, it's a {shape.type}"
             )