[Feature] Save real ucl types when exporting to Lua

diff --git a/contrib/libucl/lua_ucl.c b/contrib/libucl/lua_ucl.c
index 85f16a237d1fd7bbca5672ff5eb649e6ad6767c6..138522044d3efe4ce9b3e569dc7d4ab386c25b07 100644 (file)
--- a/contrib/libucl/lua_ucl.c
+++ b/contrib/libucl/lua_ucl.c
@@ -68,8 +68,11 @@ func = "huh";
 
 #define PARSER_META "ucl.parser.meta"
 #define EMITTER_META "ucl.emitter.meta"
-#define NULL_META "null.emitter.meta"
+#define NULL_META "ucl.null.meta"
 #define OBJECT_META "ucl.object.meta"
+#define UCL_OBJECT_TYPE_META "ucl.type.object"
+#define UCL_ARRAY_TYPE_META "ucl.type.array"
+#define UCL_IMPL_ARRAY_TYPE_META "ucl.type.impl_array"
 
 static int ucl_object_lua_push_array (lua_State *L, const ucl_object_t *obj);
 static int ucl_object_lua_push_scalar (lua_State *L, const ucl_object_t *obj, bool allow_array);
@@ -141,25 +144,22 @@ ucl_object_lua_push_object (lua_State *L, const ucl_object_t *obj,
 {
        const ucl_object_t *cur;
        ucl_object_iter_t it = NULL;
-       int nelt = 0;
 
        if (allow_array && obj->next != NULL) {
                /* Actually we need to push this as an array */
                return ucl_object_lua_push_array (L, obj);
        }
 
-       /* Optimize allocation by preallocation of table */
-       while (ucl_object_iterate (obj, &it, true) != NULL) {
-               nelt ++;
-       }
-
-       lua_createtable (L, 0, nelt);
+       lua_createtable (L, 0, obj->len);
        it = NULL;
 
        while ((cur = ucl_object_iterate (obj, &it, true)) != NULL) {
                ucl_object_lua_push_element (L, ucl_object_key (cur), cur);
        }
 
+       luaL_getmetatable (L, UCL_OBJECT_TYPE_META);
+       lua_setmetatable (L, -2);
+
        return 1;
 }
 
@@ -187,6 +187,9 @@ ucl_object_lua_push_array (lua_State *L, const ucl_object_t *obj)
                        i ++;
                }
 
+               luaL_getmetatable (L, UCL_ARRAY_TYPE_META);
+               lua_setmetatable (L, -2);
+
                ucl_object_iterate_free (it);
        }
        else {
@@ -202,6 +205,9 @@ ucl_object_lua_push_array (lua_State *L, const ucl_object_t *obj)
                        lua_rawseti (L, -2, i);
                        i ++;
                }
+
+               luaL_getmetatable (L, UCL_IMPL_ARRAY_TYPE_META);
+               lua_setmetatable (L, -2);
        }
 
        return 1;
@@ -294,50 +300,93 @@ ucl_object_lua_fromtable (lua_State *L, int idx, ucl_string_flags_t flags)
        ucl_object_t *obj, *top = NULL;
        size_t keylen;
        const char *k;
-       bool is_array = true;
+       bool is_array = true, is_implicit = false, found_mt = false;
        int max = INT_MIN;
 
        if (idx < 0) {
                /* For negative indicies we want to invert them */
                idx = lua_gettop (L) + idx + 1;
        }
-       /* Check for array */
-       lua_pushnil (L);
-       while (lua_next (L, idx) != 0) {
-               if (lua_type (L, -2) == LUA_TNUMBER) {
-                       double num = lua_tonumber (L, -2);
-                       if (num == (int)num) {
-                               if (num > max) {
-                                       max = num;
-                               }
+
+       /* First, we check from metatable */
+       if (luaL_getmetafield (L, idx, "class") != 0) {
+
+               if (lua_type (L, -1) == LUA_TSTRING) {
+                       const char *classname = lua_tostring (L, -1);
+
+                       if (strcmp (classname, UCL_OBJECT_TYPE_META) == 0) {
+                               is_array = false;
+                               found_mt = true;
+                       } else if (strcmp (classname, UCL_ARRAY_TYPE_META) == 0) {
+                               is_array = true;
+                               found_mt = true;
+                       } else if (strcmp (classname, UCL_IMPL_ARRAY_TYPE_META) == 0) {
+                               is_array = true;
+                               is_implicit = true;
+                               found_mt = true;
                        }
-                       else {
-                               /* Keys are not integer */
+               }
+
+               lua_pop (L, 1);
+       }
+
+       if (!found_mt) {
+               /* Check for array */
+               lua_pushnil (L);
+               while (lua_next (L, idx) != 0) {
+                       if (lua_type (L, -2) == LUA_TNUMBER) {
+                               double num = lua_tonumber (L, -2);
+                               if (num == (int) num) {
+                                       if (num > max) {
+                                               max = num;
+                                       }
+                               } else {
+                                       /* Keys are not integer */
+                                       lua_pop (L, 2);
+                                       is_array = false;
+                                       break;
+                               }
+                       } else {
+                               /* Keys are not numeric */
                                lua_pop (L, 2);
                                is_array = false;
                                break;
                        }
+                       lua_pop (L, 1);
                }
-               else {
-                       /* Keys are not numeric */
-                       lua_pop (L, 2);
-                       is_array = false;
-                       break;
-               }
-               lua_pop (L, 1);
+       }
+       else if (is_array) {
+#if LUA_VERSION_NUM >= 502
+               max = lua_rawlen (L, idx);
+#else
+               max = lua_objlen (L, idx);
+#endif
        }
 
        /* Table iterate */
        if (is_array) {
                int i;
 
-               top = ucl_object_typed_new (UCL_ARRAY);
+               if (!is_implicit) {
+                       top = ucl_object_typed_new (UCL_ARRAY);
+               }
+               else {
+                       top = NULL;
+               }
+
                for (i = 1; i <= max; i ++) {
                        lua_pushinteger (L, i);
                        lua_gettable (L, idx);
+
                        obj = ucl_object_lua_fromelt (L, lua_gettop (L), flags);
+
                        if (obj != NULL) {
-                               ucl_array_append (top, obj);
+                               if (is_implicit) {
+                                       DL_APPEND (top, obj);
+                               }
+                               else {
+                                       ucl_array_append (top, obj);
+                               }
                        }
                        lua_pop (L, 1);
                }
@@ -1134,6 +1183,49 @@ lua_ucl_object_mt (lua_State *L)
        lua_pop (L, 1);
 }
 
+static void
+lua_ucl_types_mt (lua_State *L)
+{
+       luaL_newmetatable (L, UCL_OBJECT_TYPE_META);
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "__tostring");
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "tostring");
+
+       lua_pushstring (L, UCL_OBJECT_TYPE_META);
+       lua_setfield (L, -2, "class");
+
+       lua_pop (L, 1);
+
+       luaL_newmetatable (L, UCL_ARRAY_TYPE_META);
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "__tostring");
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "tostring");
+
+       lua_pushstring (L, UCL_ARRAY_TYPE_META);
+       lua_setfield (L, -2, "class");
+
+       lua_pop (L, 1);
+
+       luaL_newmetatable (L, UCL_IMPL_ARRAY_TYPE_META);
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "__tostring");
+
+       lua_pushcfunction (L, lua_ucl_object_tostring);
+       lua_setfield (L, -2, "tostring");
+
+       lua_pushstring (L, UCL_IMPL_ARRAY_TYPE_META);
+       lua_setfield (L, -2, "class");
+
+       lua_pop (L, 1);
+}
+
 static int
 lua_ucl_to_json (lua_State *L)
 {
@@ -1281,6 +1373,7 @@ luaopen_ucl (lua_State *L)
        lua_ucl_parser_mt (L);
        lua_ucl_null_mt (L);
        lua_ucl_object_mt (L);
+       lua_ucl_types_mt (L);
 
        /* Create the refs weak table: */
        lua_createtable (L, 0, 2);