Simple trick I came up with to discourage myself from cheating in a single player world with cheats enabled.

I was tired of falling to temptation of using cheats, so I found a pretty good way to discourage myself and so far it has worked.

Take a repeating command block, put it in a faraway place from spawn at bedrock level. Put the command "gamemode survival [your name]." The game will attempt to set your gamemode to Survival 20 times per second, making it impossible to switch to Creative or Spectator mode to escape dangerous situations, for example.