address comments

miri-script/src/commands.rs

@@ -177,7 +177,7 @@ impl Command {
                     bless,
                     flags,
                     target,
-                    coverage.then_some(crate::coverage::CoverageReport::new()?),
+                    coverage,
                 ),
             Command::Run { dep, verbose, many_seeds, target, edition, flags } =>
                 Self::run(dep, verbose, many_seeds, target, edition, flags),
@@ -468,10 +468,12 @@ impl Command {
         bless: bool,
         mut flags: Vec<String>,
         target: Option<String>,
-        coverage: Option<crate::coverage::CoverageReport>,
+        coverage: bool,
     ) -> Result<()> {
         let mut e = MiriEnv::new()?;
 
+        let coverage = coverage.then_some(crate::coverage::CoverageReport::new()?);
+
         if let Some(report) = &coverage {
             report.add_env_vars(&mut e)?;
         }

miri-script/src/coverage.rs

@@ -1,4 +1,4 @@
-use std::ffi::OsString;
+use std::path::PathBuf;
 
 use anyhow::{Context, Result};
 use path_macro::path;
@@ -57,8 +57,7 @@ impl CoverageReport {
         let merged_file = path!(e.miri_dir / "target" / "coverage.profdata");
 
         // Merge the profraw files
-        let profraw_files_cloned = profraw_files.iter();
-        cmd!(e.sh, "{profdata_bin} merge -sparse {profraw_files_cloned...} -o {merged_file}")
+        cmd!(e.sh, "{profdata_bin} merge -sparse {profraw_files...} -o {merged_file}")
             .quiet()
             .run()?;
 
@@ -72,6 +71,7 @@ impl CoverageReport {
         )
         .run()?;
 
+        println!("Profile data saved in {}", merged_file.display());
         Ok(())
     }
 
@@ -80,12 +80,12 @@ impl CoverageReport {
     /// # Errors
     ///
     /// An error will be returned if `self.path` can't be read.
-    fn profraw_files(&self) -> Result<Vec<OsString>> {
+    fn profraw_files(&self) -> Result<Vec<PathBuf>> {
         Ok(std::fs::read_dir(&self.path)?
             .filter_map(|r| r.ok())
+            .filter(|e| e.file_type().is_ok_and(|t| t.is_file()))
             .map(|e| e.path())
             .filter(|p| p.extension().is_some_and(|e| e == "profraw"))
-            .map(|p| p.as_os_str().to_os_string())
             .collect())
     }
 }