error: module `FooBar` should have a snake case name
  --> $DIR/lint-non-snake-case-modules.rs:4:5
   |
LL | mod FooBar {
   |     ^^^^^^ help: convert the identifier to snake case: `foo_bar`
   |
note: the lint level is defined here
  --> $DIR/lint-non-snake-case-modules.rs:1:9
   |
LL | #![deny(non_snake_case)]
   |         ^^^^^^^^^^^^^^

error: aborting due to 1 previous error