extract is_table_empty to separate utils lib

docker/nginx/libs/skynet/account.lua

@@ -14,15 +14,6 @@ local anon_limits = {
     ["registry"] = 250
 }
 
--- utility function for checking if table is empty
-function is_table_empty(check)
-    -- bind next to local variable to achieve ultimate efficiency
-    -- https://stackoverflow.com/a/1252776
-    local next = next
-
-    return next(check) == nil
-end
-
 -- get all non empty authentication headers from request, we want to return
 -- all of them and let accounts service deal with validation and prioritisation
 function _M.get_auth_headers()
@@ -69,10 +60,11 @@ end
 
 function _M.get_account_limits()
     local cjson = require('cjson')
+    local utils = require('utils')
     local auth_headers = _M.get_auth_headers()
 
     -- simple case of anonymous request - none of available auth headers exist
-    if is_table_empty(auth_headers) then
+    if utils.is_table_empty(auth_headers) then
         return anon_limits
     end
 

docker/nginx/libs/utils.lua

@@ -0,0 +1,12 @@
+local _M = {}
+
+-- utility function for checking if table is empty
+function is_table_empty(check)
+    -- bind next to local variable to achieve ultimate efficiency
+    -- https://stackoverflow.com/a/1252776
+    local next = next
+
+    return next(check) == nil
+end
+
+return _M

docker/nginx/libs/utils.spec.lua

@@ -0,0 +1,11 @@
+local utils = require('utils')
+
+describe("is_table_empty", function()
+    it("should return true for empty table", function()
+        assert.is_true(utils.is_table_empty({}))
+    end)
+
+    it("should return false for not empty table", function()
+        assert.is_false(utils.is_table_empty({ ["foo"] = "bar" }))
+    end)
+end)