Refactor version check into its own function, add IncompatiblePatchError

Author: Mateo Mongour

Patch.py

@@ -9,8 +9,6 @@
     ModuleUpdate.update()
 
 from worlds.Files import AutoPatchRegister, APAutoPatchInterface
-from worlds.AutoWorld import AutoWorldRegister
-from Utils import messagebox
 
 
 class RomMeta(TypedDict):
@@ -19,18 +17,16 @@ class RomMeta(TypedDict):
     player_name: str
 
 
+class IncompatiblePatchError(Exception):
+    pass
+
+
 def create_rom_file(patch_file: str) -> Tuple[RomMeta, str]:
     auto_handler = AutoPatchRegister.get_handler(patch_file)
     if auto_handler:
         handler: APAutoPatchInterface = auto_handler(patch_file)
         handler.read()
-        game_version = AutoWorldRegister.world_types[handler.game].world_version if handler.game else None
-        if game_version and handler.world_version and game_version != handler.world_version:
-            info_msg = "This patch was generated with " \
-                       f"{handler.game} version {handler.world_version.as_simple_string()}, " \
-                       f"but its currently installed version is {game_version.as_simple_string()}. " \
-                       "You may encounter errors while patching or connecting."
-            messagebox("APWorld version mismatch", info_msg, False)
+        handler.verify_version()
         target = os.path.splitext(patch_file)[0]+handler.result_file_ending
         handler.patch(target)
         return {"server": handler.server,

worlds/Files.py

@@ -288,6 +288,22 @@ class APAutoPatchInterface(APPatch, abc.ABC, metaclass=AutoPatchRegister):
     def patch(self, target: str) -> None:
         """ create the output file with the file name `target` """
 
+    def verify_version(self) -> None:
+        """
+        Verify compatibility between a game's currently installed
+        world version and the version used for generation.
+        Warns the user or raises an IncompatiblePatchError if the versions are too different.
+        """
+        from Utils import messagebox
+        from .AutoWorld import AutoWorldRegister
+        game_version = AutoWorldRegister.world_types[self.game].world_version if self.game else None
+        if game_version and self.world_version and game_version != self.world_version:
+            info_msg = "This patch was generated with " \
+                       f"{self.game} version {self.world_version.as_simple_string()}, " \
+                       f"but its currently installed version is {game_version.as_simple_string()}. " \
+                       "You may encounter errors while patching or connecting."
+            messagebox("APWorld version mismatch", info_msg, False)
+
 
 class APProcedurePatch(APAutoPatchInterface):
     """