fix: path encoding on wasi

Author: Stebalien

src/file/imp/unix.rs

@@ -108,6 +108,11 @@ pub fn reopen(_file: &File, _path: &Path) -> io::Result<File> {
 
 #[cfg(not(target_os = "redox"))]
 pub fn persist(old_path: &Path, new_path: &Path, overwrite: bool) -> io::Result<()> {
+    #[cfg(target_os = "wasi")]
+    let old_path = old_path.as_os_str().as_encoded_bytes();
+    #[cfg(target_os = "wasi")]
+    let new_path = new_path.as_os_str().as_encoded_bytes();
+
     if overwrite {
         rename(old_path, new_path)?;
     } else {