lua: Fixed broken __lt/__le operators caused by lnum patch.

This was found while investigating why luarocks does not work. It was
traced to a quite old lnum patch for 5.1.3. I compared against the
latest 5.1.4 patch - https://github.com/LuaDist/lualnum and discovered
the lessthan/lessequal evaluation was not falling through to the
call_orderTM (tag methods).

I have tested LuCI (simple tests) and used the following lua code to
validate the patch (both host and target patches supplied): -

> local my_mt = {
> __eq = function(v1, v2)
> print("__eq")
> return false
> end,
> __lt = function(v1, v2)
> print("__lt")
> return false
> end,
> __le = function(v1, v2)
> print("__le")
> return false
> end
> }
>
> function get_my(vstring)
> local my = {}
> my.string = vstring;
> setmetatable(my, my_mt);
> return my;
> end
>
> local a = get_my("1.0")
> local b = get_my("1.0")
>
> local eq_works = a == b;
> local lt_works = a < b;
> local gt_works = a > b;
>
> local lte_works = a <= b;
> local gte_works = a >= b;

Without the patch the following error will be presented: -

“attempt to compare two table values”

Signed-off-by: David Thornley <david.thornley@touchstargroup.com>
This commit is contained in:
David Thornley 2016-05-11 13:28:53 +10:00 committed by Jo-Philipp Wich
parent 45e0f8b826
commit da0226fa7e
2 changed files with 44 additions and 0 deletions

View File

@ -0,0 +1,22 @@
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -284,7 +284,8 @@ int luaV_lessthan (lua_State *L, const T
else
return luai_numlt( nvalue_fast(l), cast_num(ivalue(r)) );
- } else if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
+ }
+ if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
return res;
return luaG_ordererror(L, l, r);
@@ -322,7 +323,8 @@ static int lessequal (lua_State *L, cons
else
return luai_numle( nvalue_fast(l), cast_num(ivalue(r)) );
- } else if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */
+ }
+ if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */
return res;
else if ((res = call_orderTM(L, r, l, TM_LT)) != -1) /* else try `lt' */
return !res;

View File

@ -0,0 +1,22 @@
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -284,7 +284,8 @@ int luaV_lessthan (lua_State *L, const T
else
return luai_numlt( nvalue_fast(l), cast_num(ivalue(r)) );
- } else if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
+ }
+ if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
return res;
return luaG_ordererror(L, l, r);
@@ -322,7 +323,8 @@ static int lessequal (lua_State *L, cons
else
return luai_numle( nvalue_fast(l), cast_num(ivalue(r)) );
- } else if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */
+ }
+ if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */
return res;
else if ((res = call_orderTM(L, r, l, TM_LT)) != -1) /* else try `lt' */
return !res;