diff --git a/src/cmd_config.rs b/src/cmd_config.rs
index d7b64fb..8e2894c 100644
--- a/src/cmd_config.rs
+++ b/src/cmd_config.rs
@@ -74,7 +74,7 @@ pub fn config(_cmd_version: CmdConfig) -> XResult<()> {
 
     let mut table = Table::new(config_profiles);
     table.with(Style::modern());
-    println!("{}", table.to_string());
+    println!("{}", table);
 
     Ok(())
 }
\ No newline at end of file
diff --git a/src/cmd_decrypt.rs b/src/cmd_decrypt.rs
index 2672bef..5e6f594 100644
--- a/src/cmd_decrypt.rs
+++ b/src/cmd_decrypt.rs
@@ -160,7 +160,7 @@ fn decrypt_file(file_in: &mut File, file_out: &mut File, key: &[u8], nonce: &[u8
     let mut total_len = 0;
     let mut buffer = [0u8; 1024 * 8];
     let key = opt_result!(key.try_into(), "Key is not 32 bytes: {}");
-    let mut decryptor = aes_gcm_stream::Aes256GcmStreamDecryptor::new(key, &nonce);
+    let mut decryptor = aes_gcm_stream::Aes256GcmStreamDecryptor::new(key, nonce);
     let mut gz_decoder = GzStreamDecoder::new();
     loop {
         let len = opt_result!(file_in.read(&mut buffer), "Read file failed: {}");
@@ -202,9 +202,7 @@ fn try_decrypt_key(config: &Option<TinyEncryptConfig>,
         TinyEncryptEnvelopType::PgpX25519 => try_decrypt_key_ecdh_pgp_x25519(envelop, pin),
         TinyEncryptEnvelopType::Ecdh => try_decrypt_key_ecdh(config, envelop, pin, ENC_AES256_GCM_P256, slot),
         TinyEncryptEnvelopType::EcdhP384 => try_decrypt_key_ecdh(config, envelop, pin, ENC_AES256_GCM_P384, slot),
-        unknown_type => {
-            return simple_error!("Unknown or not supported type: {}", unknown_type.get_name());
-        }
+        unknown_type => simple_error!("Unknown or not supported type: {}", unknown_type.get_name()),
     }
 }
 
@@ -233,7 +231,7 @@ fn try_decrypt_key_ecdh(config: &Option<TinyEncryptConfig>,
     );
     let shared_secret = opt_result!(decrypt_data(
                 &mut yk,
-                &epk_bytes,
+                epk_bytes,
                 algo_id,
                 slot_id,
             ), "Decrypt via PIV card failed: {}");
@@ -274,7 +272,7 @@ fn try_decrypt_key_pgp(envelop: &TinyEncryptEnvelop, pin: &Option<String>) -> XR
 
     let pgp_envelop = &envelop.encrypted_key;
     debugging!("PGP envelop: {}", &pgp_envelop);
-    let pgp_envelop_bytes = opt_result!(util::decode_base64(&pgp_envelop), "Decode PGP envelop failed: {}");
+    let pgp_envelop_bytes = opt_result!(util::decode_base64(pgp_envelop), "Decode PGP envelop failed: {}");
 
     let key = trans.decipher(Cryptogram::RSA(&pgp_envelop_bytes))?;
     Ok(key)
diff --git a/src/cmd_encrypt.rs b/src/cmd_encrypt.rs
index 2e985eb..745739f 100644
--- a/src/cmd_encrypt.rs
+++ b/src/cmd_encrypt.rs
@@ -113,7 +113,7 @@ fn encrypt_single(path: &PathBuf, envelops: &[&TinyEncryptConfigEnvelop], cmd_en
     util::require_file_not_exists(path_out.as_str())?;
 
     let (key, nonce) = util::make_key256_and_nonce();
-    let envelops = encrypt_envelops(&key, &envelops)?;
+    let envelops = encrypt_envelops(&key, envelops)?;
 
     let encrypted_comment = match &cmd_encrypt.encrypted_comment {
         None => None,
@@ -200,7 +200,7 @@ fn encrypt_file(file_in: &mut File, file_out: &mut File, key: &[u8], nonce: &[u8
             GzStreamEncoder::new(Compression::new(*compress_level))
         }
     };
-    let mut encryptor = aes_gcm_stream::Aes256GcmStreamEncryptor::new(key, &nonce);
+    let mut encryptor = aes_gcm_stream::Aes256GcmStreamEncryptor::new(key, nonce);
     loop {
         let len = opt_result!(file_in.read(&mut buffer), "Read file failed: {}");
         if len == 0 {
@@ -292,7 +292,7 @@ fn encrypt_envelop_shared_secret(key: &[u8],
         header: WrapKeyHeader {
             kid: None, // Some(envelop.kid.clone()),
             enc: enc_type.to_string(),
-            e_pub_key: util::encode_base64_url_no_pad(&ephemeral_spki),
+            e_pub_key: util::encode_base64_url_no_pad(ephemeral_spki),
         },
         nonce,
         encrypted_data: encrypted_key,
diff --git a/src/cmd_info.rs b/src/cmd_info.rs
index de8e306..28d840f 100644
--- a/src/cmd_info.rs
+++ b/src/cmd_info.rs
@@ -81,12 +81,12 @@ pub fn info_single(path: &PathBuf, cmd_info: &CmdInfo) -> XResult<()> {
             ));
         })
     );
-    meta.pgp_fingerprint.map(|fingerprint| {
+    if let Some(fingerprint) = meta.pgp_fingerprint {
         infos.push(format!("{}: {}", header("PGP fingerprint"), fingerprint));
-    });
-    meta.comment.map(|comment| {
+    }
+    if let Some(comment) = meta.comment {
         infos.push(format!("{}: {}", header("Comment"), comment));
-    });
+    }
     infos.push(format!("{}: {}", header("Encrypted comment"), to_yes_or_no(&meta.encrypted_comment)));
     infos.push(format!("{}: {}", header("Encrypted meta"), to_yes_or_no(&meta.encrypted_meta)));
     let encryption_algorithm = if let Some(encryption_algorithm) = &meta.encryption_algorithm {
diff --git a/src/config.rs b/src/config.rs
index 0e2b6db..7605a4c 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -57,12 +57,12 @@ impl TinyEncryptConfig {
             serde_json::from_str(&config_contents),"Parse file: {}, failed: {}", file);
         let mut splitted_profiles = HashMap::new();
         for (k, v) in config.profiles.into_iter() {
-            if !k.contains(",") {
+            if !k.contains(',') {
                 splitted_profiles.insert(k, v);
             } else {
-                k.split(",")
+                k.split(',')
                     .map(|k| k.trim())
-                    .filter(|k| k.len() > 0)
+                    .filter(|k| !k.is_empty())
                     .for_each(|k| {
                         splitted_profiles.insert(k.to_string(), v.clone());
                     });
@@ -73,11 +73,11 @@ impl TinyEncryptConfig {
     }
 
     pub fn find_first_arg_by_kid(&self, kid: &str) -> Option<&String> {
-        self.find_args_by_kid(kid).map(|a| a.iter().next()).flatten()
+        self.find_args_by_kid(kid).and_then(|a| a.iter().next())
     }
 
     pub fn find_args_by_kid(&self, kid: &str) -> Option<&Vec<String>> {
-        self.find_by_kid(kid).map(|e| e.args.as_ref()).flatten()
+        self.find_by_kid(kid).and_then(|e| e.args.as_ref())
     }
 
     pub fn find_by_kid(&self, kid: &str) -> Option<&TinyEncryptConfigEnvelop> {
@@ -103,7 +103,7 @@ impl TinyEncryptConfig {
             }
         }
         let mut envelops: Vec<_> = matched_envelops_map.values()
-            .map(|envelop| *envelop)
+            .copied()
             .collect();
         if envelops.is_empty() {
             return simple_error!("Profile: {} has no valid envelopes found", profile);
diff --git a/src/spec.rs b/src/spec.rs
index 3ff19a0..a46df17 100644
--- a/src/spec.rs
+++ b/src/spec.rs
@@ -1,15 +1,15 @@
 use std::fs::Metadata;
-use flate2::Compression;
 
+use flate2::Compression;
 use rust_util::{opt_result, util_time, XResult};
 use rust_util::util_time::get_millis;
 use serde::{Deserialize, Serialize};
-use crate::{compress, crypto_aes};
 
+use crate::{compress, crypto_aes};
 use crate::util::{encode_base64, get_user_agent, SALT_META, TINY_ENC_AES_GCM};
 
-pub const TINY_ENCRYPT_VERSION_10: &'static str = "1.0";
-pub const TINY_ENCRYPT_VERSION_11: &'static str = "1.1";
+pub const TINY_ENCRYPT_VERSION_10: &str = "1.0";
+pub const TINY_ENCRYPT_VERSION_11: &str = "1.1";
 
 /// Specification: [Tiny Encrypt Spec V1.1](https://git.hatter.ink/hatter/tiny-encrypt-java/src/branch/master/TinyEncryptSpecV1.1.md)
 #[derive(Clone, Debug, Serialize, Deserialize)]
@@ -105,7 +105,7 @@ impl EncEncryptedMeta {
         decrypted = opt_result!(compress::decompress(&decrypted), "Decode faield: {}");
         let meta = opt_result!(
             serde_json::from_slice::<Self>(&decrypted), "Parse failed: {}");
-        return Ok(meta);
+        Ok(meta)
     }
 
     pub fn seal(&self, key: &[u8], nonce: &[u8]) -> XResult<Vec<u8>> {
diff --git a/src/util.rs b/src/util.rs
index 802fb29..3193905 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -1,6 +1,6 @@
 use std::{fs, io};
 use std::io::Write;
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use base64::Engine;
 use base64::engine::general_purpose;
@@ -22,10 +22,10 @@ pub const TINY_ENC_COMPRESSED_MAGIC_TAG: u16 = 0x02;
 pub const SALT_COMMENT: &[u8] = b"salt:comment";
 pub const SALT_META: &[u8] = b"salt:meta";
 
-pub fn get_file_name(path: &PathBuf) -> String {
+pub fn get_file_name(path: &Path) -> String {
     let path_display = format!("{}", path.display());
-    if path_display.contains("/") {
-        if let Some(p) = path_display.split("/").last() {
+    if path_display.contains('/') {
+        if let Some(p) = path_display.split('/').last() {
             return p.to_string();
         }
     }
@@ -80,8 +80,7 @@ pub fn simple_kdf(input: &[u8]) -> Vec<u8> {
     let input = hex::decode(sha256::digest(input)).unwrap();
     let input = hex::decode(sha256::digest(input)).unwrap();
     let input = hex::decode(sha256::digest(input)).unwrap();
-    let input = hex::decode(sha256::digest(input)).unwrap();
-    input
+    hex::decode(sha256::digest(input)).unwrap()
 }
 
 pub fn decode_base64(input: &str) -> XResult<Vec<u8>> {
diff --git a/src/util_ecdh.rs b/src/util_ecdh.rs
index 5898699..deab2bd 100644
--- a/src/util_ecdh.rs
+++ b/src/util_ecdh.rs
@@ -24,7 +24,7 @@ use p256::elliptic_curve::sec1::FromEncodedPoint;
 
 pub fn compute_shared_secret(public_key_point_hex: &str) -> XResult<(Vec<u8>, Vec<u8>)> {
     let public_key_point_bytes = opt_result!(hex::decode(public_key_point_hex), "Parse public key point hex failed: {}");
-    let encoded_point = opt_result!(EncodedPoint::from_bytes(&public_key_point_bytes), "Parse public key point failed: {}");
+    let encoded_point = opt_result!(EncodedPoint::from_bytes(public_key_point_bytes), "Parse public key point failed: {}");
     let public_key = PublicKey::from_encoded_point(&encoded_point).unwrap();
 
     let esk = EphemeralSecret::random(&mut OsRng);
diff --git a/src/util_p384.rs b/src/util_p384.rs
index 73b0209..aaf2ad2 100644
--- a/src/util_p384.rs
+++ b/src/util_p384.rs
@@ -8,7 +8,7 @@ use p384::elliptic_curve::sec1::FromEncodedPoint;
 
 pub fn compute_p384_shared_secret(public_key_point_hex: &str) -> XResult<(Vec<u8>, Vec<u8>)> {
     let public_key_point_bytes = opt_result!(hex::decode(public_key_point_hex), "Parse public key point hex failed: {}");
-    let encoded_point = opt_result!(EncodedPoint::from_bytes(&public_key_point_bytes), "Parse public key point failed: {}");
+    let encoded_point = opt_result!(EncodedPoint::from_bytes(public_key_point_bytes), "Parse public key point failed: {}");
     let public_key = PublicKey::from_encoded_point(&encoded_point).unwrap();
 
     let esk = EphemeralSecret::random(&mut OsRng);
diff --git a/src/wrap_key.rs b/src/wrap_key.rs
index ed2f543..0ce392f 100644
--- a/src/wrap_key.rs
+++ b/src/wrap_key.rs
@@ -37,7 +37,7 @@ impl WrapKey {
         if !wk.starts_with("WK:") {
             return simple_error!("Wrap key string must starts with WK:");
         }
-        let wks = wk.split(".").collect::<Vec<_>>();
+        let wks = wk.split('.').collect::<Vec<_>>();
         if wks.len() != 3 {
             return simple_error!("Invalid wrap key.");
         }