error: module `FooBar` should have a snake case name such as `foo_bar`
  --> $DIR/lint-non-snake-case-modules.rs:14:1
   |
LL | / mod FooBar { //~ ERROR module `FooBar` should have a snake case name such as `foo_bar`
LL | |     pub struct S;
LL | | }
   | |_^
   |
note: lint level defined here
  --> $DIR/lint-non-snake-case-modules.rs:11:9
   |
LL | #![deny(non_snake_case)]
   |         ^^^^^^^^^^^^^^

error: aborting due to previous error