Improve to_dict for any (#47)

* Improve to_dict for any

* Fix errors on empty any

* Remove generated code to pass typechecking

Author: AdrienVannson

src/betterproto2_compiler/known_types/any.py

@@ -1,3 +1,5 @@
+import typing
+
 import betterproto2
 
 from betterproto2_compiler.lib.google.protobuf import Any as VanillaAny
@@ -18,19 +20,37 @@ def pack(self, message: betterproto2.Message, message_pool: "betterproto2.Messag
         self.type_url = message_pool.type_to_url[type(message)]
         self.value = bytes(message)
 
-    def unpack(self, message_pool: "betterproto2.MessagePool | None" = None) -> betterproto2.Message:
+    def unpack(self, message_pool: "betterproto2.MessagePool | None" = None) -> betterproto2.Message | None:
         """
         Return the message packed inside the `Any` object.
 
         The target message type must be registered in the message pool, which is done automatically when the module
         defining the message type is imported.
         """
+        if not self.type_url:
+            return None
+
         message_pool = message_pool or default_message_pool
 
-        message_type = message_pool.url_to_type[self.type_url]
+        try:
+            message_type = message_pool.url_to_type[self.type_url]
+        except KeyError:
+            raise TypeError(f"Can't unpack unregistered type: {self.type_url}")
 
         return message_type().parse(self.value)
 
-    def to_dict(self) -> dict:  # pyright: ignore [reportIncompatibleMethodOverride]
-        # TOOO improve when dict is updated
-        return {"@type": self.type_url, "value": self.unpack().to_dict()}
+    def to_dict(self, **kwargs) -> dict[str, typing.Any]:
+        # TODO allow passing a message pool to `to_dict`
+        output: dict[str, typing.Any] = {"@type": self.type_url}
+
+        value = self.unpack()
+
+        if value is None:
+            return output
+
+        if type(value).to_dict == betterproto2.Message.to_dict:
+            output.update(value.to_dict(**kwargs))
+        else:
+            output["value"] = value.to_dict(**kwargs)
+
+        return output

src/betterproto2_compiler/lib/google/protobuf/__init__.py

@@ -22,6 +22,7 @@ import builtins
 import datetime
 import warnings
 from collections.abc import AsyncIterable, AsyncIterator, Iterable
+import typing
 from typing import TYPE_CHECKING
 
 {% if output_file.settings.pydantic_dataclasses %}