lua: fix lua 5.5 engine compatibility

src/instead/instead.c

@@ -735,12 +735,23 @@ static int luaB_print (lua_State *L) {
   for (i = 1; i <= n; i++) {  /* for each argument */
     size_t l;
     const char *s = luaL_tolstring(L, i, &l);  /* convert it to string */
+#if LUA_VERSION_NUM >= 505
+    if (i > 1)
+      fputs("\t", stdout);
+    fwrite(s, sizeof(char), l, stdout);
+#else
     if (i > 1)  /* not the first element? */
       lua_writestring("\t", 1);  /* add a tab before it */
     lua_writestring(s, l);  /* print it */
+#endif
     lua_pop(L, 1);  /* pop result */
   }
+#if LUA_VERSION_NUM >= 505
+  fputs("\n", stdout);
+  fflush(stdout);
+#else
   lua_writeline();
+#endif
   return 0;
 }
 #endif

stead/stead3/stead.lua

@@ -1533,9 +1533,9 @@ std.obj = std.class {
 
     for i = 1, #s.obj do
       local v = s.obj[i]
-      o, l, i = v:srch(w)
+      o, l, idx = v:srch(w)
       if o then
-        return o, l, i
+        return o, l, idx
       end
     end
   end;
@@ -1547,9 +1547,9 @@ std.obj = std.class {
     end
     for i = 1, #s.obj do
       local v = s.obj[i]
-      o, l, i = v:lookup(w)
+      o, l, idx = v:lookup(w)
       if o then
-        return o, l, i
+        return o, l, idx
       end
     end
   end;

tests/games/integration/main3.lua

@@ -26,6 +26,24 @@ local function check_eq(name, got, want)
   end
 end
 
+-- Recursive searches return the index in the containing list, not the parent.
+local search_leaf = obj { nam = 'search_leaf' }
+local search_inner = obj {
+  nam = 'search_inner',
+  obj = { obj { nam = 'search_filler' }, search_leaf },
+}
+local search_root = obj {
+  nam = 'search_root',
+  obj = { search_inner },
+}
+for _, method in ipairs { 'srch', 'lookup' } do
+  local o, l, idx = search_root[method](search_root, search_leaf)
+  check_eq(method .. " nested object", o, search_leaf)
+  check_eq(method .. " containing list", l, search_inner.obj)
+  check_eq(method .. " nested index", idx, 2)
+  check_eq(method .. " missing object", search_root[method](search_root, 'missing'), nil)
+end
+
 -- src/instead_paths.c
 check("instead_gamespath is a function", type(instead_gamespath) == "function")
 local gamespath = instead_gamespath()