Thanks, the warning should be resolved now.

warning: unused variable: `x`
  --> src/lib.rs:93:13
   |
93 |         for x in 0..100 {
   |             ^ help: if this is intentional, prefix it with an underscore: `_x`

There is no typo. You have to simplify your result. Have a look at te top of the page: 117 guys passed the Rust kata. Cheers.

Perhaps I'm just doing this wrong, but the Rust 2018 tests for basics_convert_fracts seem to have a typo. For,

testing(vec![(690, 1300), (87, 1310), (30, 40)], vec![(18078, 34060), (2262, 34060), (25545, 34060)]);

The expected answers are all missing a trailing zero.