fix ui elements related things

res/modules/internal/gui_util.lua

@@ -77,15 +77,18 @@ function Element.new(docname, name)
 end
 
 -- the engine automatically creates an instance for every ui document (layout)
-local Document = {}
-function Document.new(docname)
-    return setmetatable({name=docname}, {
-        __index=function(self, k)
-            local elem = Element.new(self.name, k)
-            rawset(self, k, elem)
-            return elem
+local Document = {
+    __index=function(self, k)
+        if type(k) ~= "string" then
+            error("element id is not a string")
         end
-    })
+        local elem = Element.new(self.name, k)
+        rawset(self, k, elem)
+        return elem
+    end
+}
+function Document.new(docname)
+    return setmetatable({name=docname}, Document)
 end
 
 local RadioGroup = {}

res/modules/internal/test.lua

@@ -70,7 +70,7 @@ function test.click(node, options)
     end
     if not node.exists then
         error(string.format("timeout %s ms exceeded: element %s does not exists",
-            math.floor(timeout), string.escape(node.id)))
+            math.floor(timeout), string.escape(rawget(node, 'name'))))
     end
 
     local center_x, center_y = get_node_center(node)
@@ -82,6 +82,9 @@ end
 
 -- TODO: replace with resolving in C++ side
 function test.find_by_attr(node, attr, value)
+    if getmetatable(node) == Document then
+        return test.find_by_attr(node.root, attr, value)
+    end
     if node[attr] == value then
         return node
     end