Lua: fix key deletion in tables

client/space_lua/stdlib/table_test.lua

@@ -126,6 +126,13 @@ assert(table.includes(t, "three"))
 assert(table.includes(t, true))
 assert(not table.includes(t, "missing"))
 
+-- Test using table as set
+local s = {}
+s["something"] = true
+assertEqual(#table.keys(s), 1)
+-- Remove from the map
+s["something"] = nil
+assertEqual(#table.keys(s), 0)
 
 -- Error cases
 local success, error = pcall(function()
@@ -147,4 +154,4 @@ local t = { 0, 1, 2, 3 }
 local idx, two = table.find(t, function(v) return v == 2 end)
 assertEqual(idx, 3)
 assertEqual(two, 2)
-assertEqual(table.find(t, function(v) return v == 4 end), nil)
+assertEqual(table.find(t, function(v) return v == 4 end), nil)