go spare vs shit oneself

go spare

verb
  • To become very angry; to become frustrated or distraught: see spare. 

  • To be available or unused. 

shit oneself

verb
  • To be very frightened or astonished (to the extent that one might lose control of one's bowels). 

  • To soil oneself. 

How often have the words go spare and shit oneself occurred in a corpus of books? (source: Google Ngram Viewer )