{"SetOption":{"value":"filetype=rust"}}
{"Put":{"state":"// helloˇ\n"}}
{"Key":"o"}
{"Get":{"state":"// hello\n// ˇ\n","mode":"Insert"}}
{"Key":"x"}
{"Key":"escape"}
{"Key":"shift-o"}
{"Get":{"state":"// hello\n// ˇ\n// x\n","mode":"Insert"}}