this derivation will be built:
  /nix/store/rxah5jm1czw3zm32rgvpsl7qj11kysid-treefmt-check.drv
building '/nix/store/rxah5jm1czw3zm32rgvpsl7qj11kysid-treefmt-check.drv'
treefmt-check> treefmt v2.5.0traversed 60 files
treefmt-check> emitted 37 files for processing
treefmt-check> formatted 37 files (1 changed) in 61ms
treefmt-check>  M crates/ssync/src/service.rs
treefmt-check> diff --git a/crates/ssync/src/service.rs b/crates/ssync/src/service.rs
treefmt-check> index d94e902..06a3478 100644
treefmt-check> --- a/crates/ssync/src/service.rs
treefmt-check> +++ b/crates/ssync/src/service.rs
treefmt-check> @@ -319,7 +319,10 @@ pub fn cmd_service_uninstall() -> Result<()> {
treefmt-check>          PathBuf::from(SYSTEM_UNIT_PATH)
treefmt-check>      };
treefmt-check>      if !unit_path.exists() {
treefmt-check> -        bail!("nothing to uninstall: {} does not exist", unit_path.display());
treefmt-check> +        bail!(
treefmt-check> +            "nothing to uninstall: {} does not exist",
treefmt-check> +            unit_path.display()
treefmt-check> +        );
treefmt-check>      }
treefmt-check>      // best effort: a masked/never-enabled unit must not block removal
treefmt-check>      if let Err(e) = systemctl(user_mode, &["disable", "--now", UNIT_NAME]) {
treefmt-check> @@ -372,11 +375,9 @@ mod tests {
treefmt-check>      #[test]
treefmt-check>      fn unit_opens_exactly_the_needed_write_paths() {
treefmt-check>          let unit = render_unit(&spec(None));
treefmt-check> -        assert!(
treefmt-check> -            unit.contains(
treefmt-check> -                "ReadWritePaths=/home/alice/.pi/agent/sessions /home/alice/.local/share/ssync"
treefmt-check> -            )
treefmt-check> -        );
treefmt-check> +        assert!(unit.contains(
treefmt-check> +            "ReadWritePaths=/home/alice/.pi/agent/sessions /home/alice/.local/share/ssync"
treefmt-check> +        ));
treefmt-check>      }
treefmt-check>  
treefmt-check>      #[test]
treefmt-check> @@ -426,7 +427,10 @@ mod tests {
treefmt-check>      fn missing_components_lists_only_what_create_would_add() {
treefmt-check>          let base = scratch("missing");
treefmt-check>          let leaf = base.join("a/b");
treefmt-check> -        assert_eq!(missing_components(&leaf), vec![leaf.clone(), base.join("a")]);
treefmt-check> +        assert_eq!(
treefmt-check> +            missing_components(&leaf),
treefmt-check> +            vec![leaf.clone(), base.join("a")]
treefmt-check> +        );
treefmt-check>          assert!(missing_components(&base).is_empty());
treefmt-check>          std::fs::remove_dir_all(&base).unwrap();
treefmt-check>      }
error: Cannot build '/nix/store/rxah5jm1czw3zm32rgvpsl7qj11kysid-treefmt-check.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/3yx27css7y2i1ds14rpxxjpxz38ygpnk-treefmt-check
       Last 25 log lines:
       >      fn unit_opens_exactly_the_needed_write_paths() {
       >          let unit = render_unit(&spec(None));
       > -        assert!(
       > -            unit.contains(
       > -                "ReadWritePaths=/home/alice/.pi/agent/sessions /home/alice/.local/share/ssync"
       > -            )
       > -        );
       > +        assert!(unit.contains(
       > +            "ReadWritePaths=/home/alice/.pi/agent/sessions /home/alice/.local/share/ssync"
       > +        ));
       >      }
       >  
       >      #[test]
       > @@ -426,7 +427,10 @@ mod tests {
       >      fn missing_components_lists_only_what_create_would_add() {
       >          let base = scratch("missing");
       >          let leaf = base.join("a/b");
       > -        assert_eq!(missing_components(&leaf), vec![leaf.clone(), base.join("a")]);
       > +        assert_eq!(
       > +            missing_components(&leaf),
       > +            vec![leaf.clone(), base.join("a")]
       > +        );
       >          assert!(missing_components(&base).is_empty());
       >          std::fs::remove_dir_all(&base).unwrap();
       >      }
       For full logs, run:
         nix log /nix/store/rxah5jm1czw3zm32rgvpsl7qj11kysid-treefmt-check.drv