error: unexpected closing delimiter: `}`
  --> $DIR/issue-68987-unmatch-issue-3.rs:8:1
   |
LL |     while cnt < j {
   |                   - the nearest open delimiter
LL |         write!&mut res, " ");
   |                            - missing open `(` for this delimiter
LL |     }
LL | }
   | ^ unexpected closing delimiter

error: aborting due to 1 previous error