Fix a bunch of "needless borrow" warnings on nightly

It looks like, despite a few false starts, they've got this warning
right; there weren't any false positives.

crates/arti-client/src/address.rs

@@ -490,7 +490,7 @@ mod test {
             "www.example.com:8000",
         );
         check(
-            &TorAddr::from(("www.example.com", 8000)).unwrap(),
+            TorAddr::from(("www.example.com", 8000)).unwrap(),
             "www.example.com:8000",
         );
         check("[2001:db8::0042]:9001".to_owned(), "[2001:db8::42]:9001");

crates/arti/src/cfg.rs

@@ -615,7 +615,7 @@ mod test {
         let example = uncomment_example_settings(example_file);
         let example: toml::Value = toml::from_str(&example).unwrap();
         // dbg!(&example);
-        let example = serde_json::to_value(&example).unwrap();
+        let example = serde_json::to_value(example).unwrap();
         // dbg!(&example);
 
         // "Exhaustive" taxonomy of the recognized configuration keys
@@ -626,8 +626,8 @@ mod test {
         // I'm not sure this is quite perfect but it is pretty good,
         // and has found a number of un-exampled config keys.
         let exhausts = [
-            serde_json::to_value(&TorClientConfig::builder()).unwrap(),
-            serde_json::to_value(&ArtiConfig::builder()).unwrap(),
+            serde_json::to_value(TorClientConfig::builder()).unwrap(),
+            serde_json::to_value(ArtiConfig::builder()).unwrap(),
         ];
 
         #[derive(Default, Debug)]

crates/tor-config/src/sources.rs

@@ -482,7 +482,7 @@ world = \"nonsense\"
         let xd = td.path().join("nonexistent.d/");
         std::fs::create_dir(&d).unwrap();
         std::fs::write(&cf, EX_TOML).unwrap();
-        std::fs::write(&df, EX2_TOML).unwrap();
+        std::fs::write(df, EX2_TOML).unwrap();
         std::fs::write(d.join("not-toml"), "SYNTAX ERROR").unwrap();
 
         let files = vec![

crates/tor-dirmgr/src/bridgedesc/bdtest.rs

@@ -149,7 +149,7 @@ fn setup() -> (TempDir, Bdm, R, M, BridgeKey, rusqlite::Connection) {
     let store = Arc::new(Mutex::new(Box::new(store) as _));
 
     let sql_path = db_tmp_dir.path().join("db.sql");
-    let conn = rusqlite::Connection::open(&sql_path).unwrap();
+    let conn = rusqlite::Connection::open(sql_path).unwrap();
 
     let bdm = BridgeDescMgr::<R, M>::new_internal(
         runtime.clone(),

crates/tor-dirmgr/src/storage/sqlite.rs

@@ -404,7 +404,7 @@ impl Store for SqliteStore {
         if let Some(row) = rows.next()? {
             let meta = cmeta_from_row(row)?;
             let fname: String = row.get(5)?;
-            let text = self.read_blob(&fname)?;
+            let text = self.read_blob(fname)?;
             Ok(Some((text, meta)))
         } else {
             Ok(None)
@@ -978,7 +978,7 @@ pub(crate) mod test {
     pub(crate) fn new_empty() -> Result<(TempDir, SqliteStore)> {
         let tmp_dir = tempdir().unwrap();
         let sql_path = tmp_dir.path().join("db.sql");
-        let conn = rusqlite::Connection::open(&sql_path)?;
+        let conn = rusqlite::Connection::open(sql_path)?;
         let blob_dir = fs_mistrust::Mistrust::builder()
             .dangerously_trust_everyone()
             .build()

crates/tor-llcrypto/src/pk/rsa.rs

@@ -267,7 +267,7 @@ impl PublicKey {
     pub fn to_rsa_identity(&self) -> RsaIdentity {
         use crate::d::Sha1;
         use digest::Digest;
-        let id = Sha1::digest(&self.to_der()).into();
+        let id = Sha1::digest(self.to_der()).into();
         RsaIdentity { id }
     }
 }

crates/tor-netdoc/src/parse/parser.rs

@@ -58,7 +58,7 @@ impl<'a, K: Keyword> TokVal<'a, K> {
     /// Return the Item for this value, if there is exactly one.
     fn singleton(&self) -> Option<&Item<'a, K>> {
         match &*self.0 {
-            &[ref x] => Some(x),
+            [x] => Some(x),
             _ => None,
         }
     }

crates/tor-persist/src/fs.rs

@@ -344,7 +344,7 @@ mod test {
         assert_eq!(store.try_lock()?, LockStatus::NewlyAcquired);
         let fname = statedir.join("numbat.toml");
         let fname2 = statedir.join("quoll.json");
-        std::fs::write(&fname, "we no longer use toml files.").unwrap();
+        std::fs::write(fname, "we no longer use toml files.").unwrap();
         std::fs::write(&fname2, "{}").unwrap();
 
         // Make the store directory read-only and make sure that we can't delete from it.
@@ -358,7 +358,7 @@ mod test {
         assert_eq!(lst.len(), 3); // We can't remove the file, but we didn't freak out. Great!
                                   // Try failing to read a mode-0 file.
         std::fs::set_permissions(&statedir, rw_dir).unwrap();
-        std::fs::set_permissions(&fname2, unusable).unwrap();
+        std::fs::set_permissions(fname2, unusable).unwrap();
 
         let h: Result<Option<HashMap<String, u32>>> = store.load("quoll");
         assert!(h.is_err());

crates/tor-persist/src/fs/clean.rs

@@ -122,7 +122,7 @@ mod test {
 
         let fname1 = dir.path().join("quokka");
         let now = SystemTime::now();
-        std::fs::write(&fname1, "hello world").unwrap();
+        std::fs::write(fname1, "hello world").unwrap();
 
         let mut r = std::fs::read_dir(dir.path()).unwrap();
         let ent = r.next().unwrap().unwrap();
@@ -136,10 +136,10 @@ mod test {
         let now = SystemTime::now();
 
         let fname1 = dir.path().join("quokka.toml");
-        std::fs::write(&fname1, "hello world").unwrap();
+        std::fs::write(fname1, "hello world").unwrap();
 
         let fname2 = dir.path().join("wombat.json");
-        std::fs::write(&fname2, "greetings").unwrap();
+        std::fs::write(fname2, "greetings").unwrap();
 
         let removable_now = files_to_delete(dir.path(), now);
         assert!(removable_now.is_empty());

crates/tor-proto/src/crypto/handshake/ntor.rs

@@ -359,8 +359,8 @@ mod tests {
 
     fn make_fake_ephem_key(bytes: &[u8]) -> EphemeralSecret {
         assert_eq!(bytes.len(), 32);
-        let mut rng = FakePRNG::new(bytes);
-        EphemeralSecret::new(&mut rng)
+        let rng = FakePRNG::new(bytes);
+        EphemeralSecret::new(rng)
     }
 
     #[test]