error: character literal may only contain one codepoint
  --> $DIR/whitespace-character-literal.rs:5:30
   |
LL |     let _hair_space_around = ' x​';
   |                              ^^^^
   |
note: there are non-printing characters, the full sequence is `\u{200a}x\u{200b}`
  --> $DIR/whitespace-character-literal.rs:5:31
   |
LL |     let _hair_space_around = ' x​';
   |                               ^^
help: consider removing the non-printing characters
   |
LL |     let _hair_space_around = 'x​';
   |                               ~

error: aborting due to 1 previous error