ltj-direction.lua: make \tate etc. unusable in unrestricted horizontal mode and math...

diff --git a/src/ltj-direction.lua b/src/ltj-direction.lua
index 9d650f2..133e3e8 100644 (file)
--- a/src/ltj-direction.lua
+++ b/src/ltj-direction.lua
@@ -200,14 +200,21 @@ do
       elseif v=='adj' then
          v,name = get_adjust_dir_count(), nil
       end
+      local current_nest = tex_nest[lv]
       if tex.currentgrouptype==6 then
         ltjb.package_error(
                  'luatexja',
                  "You can't use `\\" .. name .. "' in an align",
-                "To change direction in an align, \n"
-                   .. "you shold use \\hbox or \\vbox.")
+                "To change the direction in an align, \n"
+                .. "you shold use \\hbox or \\vbox.")
+      elseif current_nest.mode == ltjs.hmode or abs(current_nest.mode) == ltjs.mmode then
+        ltjb.package_error(
+                 'luatexja',
+                "Improper `\\" .. name .. "'",
+                'You cannot change the direction in unrestricted horizontal mode \n'
+                .. 'nor math modes.')
       else
-        local h = (lv==0) and tex.lists.page_head or tex_nest[lv].head.next
+        local h = (lv==0) and tex.lists.page_head or current_nest.head.next
         local flag,w = test_list(h,lv)
         if flag==0 then
            if lv==0 and not page_direction then
@@ -225,12 +232,12 @@ do
         elseif lv==0 then
            page_direction = v
         else -- flag == 2: need to create dir whatsit.
-           local h = tex_nest[lv].head
+           local h = current_nest.head
            local hn = node.next(h)
            hn = (hn and hn.id==id_local) and hn or h
            local w = to_node(dir_pool[v]())
            insert_after_node(h,hn,w)
-           tex_nest[lv].tail = node_tail_node(w)
+           current_nest.tail = node_tail_node(w)
         end
          ensure_tex_attr(attr_icflag, 0)
       end