Merge lp:~widelands-dev/widelands/fix_immovabledescr_unpersist into lp:widelands

[GunChleoc]

Fix unpersisting of LuaImmovableDescription for tribe immovables.

This bug does not seem to be triggered currently; I found it while looking at the code.

[bunnybot (widelandsofficial)]

Continuous integration builds have changed state:

Travis build 4177. State: passed. Details: https://travis-ci.org/widelands/widelands/builds/447739050.
Appveyor build 3975. State: success. Details: https://ci.appveyor.com/project/widelands-dev/widelands/build/_widelands_dev_widelands_fix_immovabledescr_unpersist-3975.

[Notabilis (notabilis27)]

I haven't tested it, but code is looking good.

[GunChleoc (gunchleoc)]

Since we've never actually run into the bug, I guess testing will be a bit difficult anyway. Thanks for the review!

@bunnybot merge

=== modified file 'src/scripting/lua_map.cc'
--- src/scripting/lua_map.cc	2018-10-27 09:45:14 +0000
+++ src/scripting/lua_map.cc	2018-10-29 11:05:36 +0000
@@ -1868,10 +1868,13 @@
 	UNPERS_STRING("name", name);
 	const World& world = get_egbase(L).world();
 	DescriptionIndex idx = world.get_immovable_index(name);
-	if (idx == INVALID_INDEX) {
-		throw LuaError((boost::format("Immovable '%s' doesn't exist.") % name).str());
-	}
-	set_description_pointer(world.get_immovable_descr(idx));
+	if (idx != INVALID_INDEX) {
+        set_description_pointer(world.get_immovable_descr(idx));
+    } else {
+        const Tribes& tribes = get_egbase(L).tribes();
+        idx = tribes.safe_immovable_index(name);
+        set_description_pointer(tribes.get_immovable_descr(idx));
+    }
 }
 
 /* RST