To format code that requires edition 2018, create a `rustfmt.toml` [configuration](#configuring-rustfmt) file containing:
```toml
-edition = "Edition2018"
+edition = "2018"
```
## Limitations
```yaml
language: rust
-rust:
-- nightly
before_script:
- rustup component add rustfmt-preview
script:
Example:
```
- cargo fmt --emit files
+ cargo fmt -- --emit files
```
Options:
| Flag |Description| Nightly Only |
|:---:|:---:|:---:|
| files | overwrites output to files | No |
- | stdout | writes output to stdout | No |
+ | stdout | writes output to stdout | No |
| coverage | displays how much of the input file was processed | Yes |
| checkstyle | emits in a checkstyle format | Yes |