if inventory is full and you try to craft something, you will loose all the stuff used for crafting and also the item will not be crafted.
i dont know its a facepunch's bug or this plugin's bug, but i thought of reporting it here. since i am using this plugin for crafting and saw some error when it happened.

03:41:34) | Failed to call hook 'OnItemCraft' on plugin 'CraftingController v3.1.5' (FormatException: Index (zero based) must be greater than or equal to zero and less than the size of the argument list.)
  at System.Text.StringBuilder.AppendFormatHelper (System.IFormatProvider provider, System.String format, System.ParamsArray args) [0x000ff] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.String.FormatHelper (System.IFormatProvider provider, System.String format, System.ParamsArray args) [0x00023] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.String.Format (System.String format, System.Object[] args) [0x00020] in <437ba245d8404784b9fbab9b439ac908>:0 
  at Oxide.Plugins.CraftingController.GetLang (System.String langKey, System.String playerId, System.Object[] args) [0x0000e] in <7a63c4cdf9774a608f70a850d0a1fb5c>:0 
  at Oxide.Plugins.CraftingController.Message (Oxide.Core.Libraries.Covalence.IPlayer player, System.String langKey, System.Object[] args) [0x00014] in <7a63c4cdf9774a608f70a850d0a1fb5c>:0 
  at Oxide.Plugins.CraftingController.ReturnCraft (ItemCraftTask task, BasePlayer crafter) [0x00007] in <7a63c4cdf9774a608f70a850d0a1fb5c>:0 
  at Oxide.Plugins.CraftingController.OnItemCraft (ItemCraftTask task, BasePlayer crafter) [0x0009a] in <7a63c4cdf9774a608f70a850d0a1fb5c>:0 
  at Oxide.Plugins.CraftingController.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x002aa] in <7a63c4cdf9774a608f70a850d0a1fb5c>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <d09a1f46ca2f4432811bcfe45ad13c7b>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <cf88a28c7fb44d36890d85a78331cc9d>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <cf88a28c7fb44d36890d85a78331cc9d>:0​

For the message error, see https://umod.org/community/crafting-controller/24817-formatexception-at-getlang

its same with bug?

Yes if it fails to call the Lang file the hook gets canceled.