Generalize do_install

do_install previously required appending an appropriate component.Mod
class to self.mods. This could create issues in subclasses because they
might end up with the wrong type of component in self.mods.

Instead, just try/finally and refresh at the end. This removes the
requirement for a specific mod class instantiation in do_install.

ammo/controller/mod.py

@@ -840,38 +840,35 @@ def install_download(index, download) -> None:
                 for file in next(extract_to.iterdir()).iterdir():
                     file.rename(extract_to / file.name)
 
-            # Add the freshly install mod to self.mods so that an error doesn't prevent
-            # any successfully installed mods from appearing during 'install all'.
-            self.mods.append(
-                Mod(
-                    location=extract_to,
-                    game_root=self.game.directory,
-                )
-            )
-
-        if index == "all":
-            errors = []
-            for i, download in enumerate(self.downloads):
-                if download.visible:
-                    try:
-                        install_download(i, download)
-                    except Warning as e:
-                        errors.append(str(e))
-            if errors:
-                raise Warning("\n".join(errors))
-        else:
-            index = int(index)
-            try:
-                download = self.downloads[index]
-            except IndexError as e:
-                raise Warning(e)
+        try:
+            if index == "all":
+                errors = []
+                for i, download in enumerate(self.downloads):
+                    if download.visible:
+                        try:
+                            install_download(i, download)
+                        except Warning as e:
+                            errors.append(str(e))
+                if errors:
+                    raise Warning("\n".join(errors))
+            else:
+                index = int(index)
+                try:
+                    download = self.downloads[index]
+                except IndexError as e:
+                    raise Warning(e)
 
-            if not download.visible:
-                raise Warning("You can only install visible downloads.")
+                if not download.visible:
+                    raise Warning("You can only install visible downloads.")
 
-            install_download(index, download)
+                install_download(index, download)
 
-        self.do_refresh()
+        finally:
+            # Add freshly installed mods to self.mods so that an error doesn't prevent
+            # any successfully installed mods from appearing during 'install all'.
+            # This is better than adding to self.mods during install_download because
+            # subclasses of ModController might use a different class than component.Mod.
+            self.do_refresh()
 
     @requires_sync
     def do_tools(self) -> None: