1 files changed, 10 insertions, 8 deletions

diff --git a/src/luarocks/config.tl b/src/luarocks/config.tl
index 019b3885..b1f9c52d 100644
--- a/src/luarocks/config.tl
+++ b/src/luarocks/config.tl
@@ -2,7 +2,7 @@ local config = {}
 
 local persist = require("luarocks.persist")
 
-local cfg_skip = {
+local cfg_skip: {string: boolean} = {
    errorcodes = true,
    flags = true,
    platforms = true,
@@ -10,26 +10,28 @@ local cfg_skip = {
    upload_servers = true,
 }
 
-function config.should_skip(k, v)
-   return type(v) == "function" or cfg_skip[k]
+local type PersistableTable = require("luarocks.core.types.persist").PersistableTable
+
+function config.should_skip(k: string, v: any): boolean
+   return v is function or cfg_skip[k]
 end
 
-local function cleanup(tbl)
+local function cleanup(tbl: PersistableTable): PersistableTable
    local copy = {}
    for k, v in pairs(tbl) do
-      if not config.should_skip(k, v) then
+      if not (k is string and config.should_skip(k, v)) then
          copy[k] = v
       end
    end
    return copy
 end
 
-function config.get_config_for_display(cfg)
+function config.get_config_for_display(cfg: PersistableTable): PersistableTable
    return cleanup(cfg)
 end
 
-function config.to_string(cfg)
-   local cleancfg = config.get_config_for_display(cfg)
+function config.to_string(cfg: PersistableTable): string, string
+   local cleancfg: PersistableTable = config.get_config_for_display(cfg)
    return persist.save_from_table_to_string(cleancfg)
 end