Merge pull request #2424 from d-enk/fix-sign-resolve-nil-extends

fix: `doc.type.function` resolve only existing arg.extends

script/vm/sign.lua

@@ -142,6 +142,7 @@ function mt:resolve(uri, args)
         end
         if object.type == 'doc.type.function' then
             for i, arg in ipairs(object.args) do
+                if arg.extends then
                     for n in node:eachObject() do
                         if n.type == 'function'
                         or n.type == 'doc.type.function' then
@@ -153,6 +154,7 @@ function mt:resolve(uri, args)
                         end
                     end
                 end
+            end
             for i, ret in ipairs(object.returns) do
                 for n in node:eachObject() do
                     if n.type == 'function'