Error writing files: io error: Failed to find module foo in "/tmp/foo/src" None

[glandium]

When a module contains an unexpected closing bracket, it fails with the aforementioned, unrelated error.

STR:

• cargo new foo && cd foo.
• At the beginning of src/main.rs, add mod foo;.
• Create src/foo.rs file with the following content:

fn foo() {}}

• Run cargo fmt

The output from cargo fmt is Error writing files: io error: Failed to find module foo in "/tmp/foo/src" None.

The unexpected closing delimiter doesn't need to be at the end of the file (i.e. adding fn bar() {} doesn't make it fail with a better error).

Doing the same in main.rs without the separate file does show an appropriate error.