Add function for rec. converting tables to arrays

Author: SudoBobo

test/test_utils.lua

@@ -187,4 +187,33 @@ function test_utils.get_shard_key_hash(key)
     return 1 + digest.guava(num, shards_n)
 end
 
+--- This order function receives two arguments and returns true if the first
+--- argument should come first in the sorted array.
+local function sort_function(f, s)
+    local allowed_types = {["string"] = true, ["number"] = true,
+        ["boolean"] = true}
+    if allowed_types[type(f)] == nil or allowed_types[type(s)] == nil then
+        error(string.format("Sort function should not be applied to keys, " ..
+        "which types are not string, number or boolean. First arg is %s " ..
+        "and second arg is %s", type(f), type(s)))
+    end
+    return tostring(f) < tostring(s)
+end
+
+-- Converts map recursively into array. If an array with maps is
+-- encountered then all this maps will be converted too.
+function test_utils.convert_table_to_array(map)
+    if type(map) == 'table' then
+        local key_array = utils.get_keys(map)
+        table.sort(key_array, sort_function)
+        local res = {}
+        for _, k in ipairs(key_array) do
+            table.insert(res, {k, test_utils.convert_table_to_array(map[k])})
+        end
+        return res
+    else
+        return map
+    end
+end
+
 return test_utils