Refactor code based on clippy suggestions

src/set3.rs

@@ -46,8 +46,9 @@ pub fn challenge17() {
         for pad_byte in 1..=block_size {
             // preset attack vector so that paddinig is [1], [2, 2], [3, 3, 3], and so on.
             attack_vector.0[block_size - pad_byte] = pad_byte as u8;
-            for i in 0..(pad_byte - 1) {
-                attack_vector.0[block_size - 1 - i] = (pad_byte as u8) ^ intermittent_result[i];
+            for (i, intermittent_byte) in intermittent_result.iter().enumerate().take(pad_byte - 1)
+            {
+                attack_vector.0[block_size - 1 - i] = (pad_byte as u8) ^ intermittent_byte;
             }
 
             // guess attack vector so that padding is valid
@@ -129,7 +130,7 @@ pub fn challenge19() {
     }
 
     fn u8_lower(s: u8) -> u8 {
-        if s >= b'A' && s <= b'Z' {
+        if (b'A'..=b'Z').contains(&s) {
             return s + 32;
         }
         s
@@ -220,7 +221,7 @@ pub fn challenge19() {
         deciphered
     }
 
-    fn manual(decrypts: &Vec<RefCell<Vec<u8>>>) {
+    fn manual(decrypts: &[RefCell<Vec<u8>>]) {
         // Add manually guessed letters
         decrypts[0].borrow_mut()[30] = b'y';
         decrypts[2].borrow_mut()[30] = b'y';
@@ -242,16 +243,11 @@ pub fn challenge19() {
     let plaintexts = utils::read_base64_lines("data/19.txt");
     let key = Bytes::from_utf8("YELLOW SUBMARINE");
     let encrypt = |plaintext: &Bytes| -> Bytes { ctr::encrypt(&key, 0, plaintext) };
-    let ciphers: Vec<Bytes> = plaintexts.iter().map(|ct| encrypt(&ct)).collect();
+    let ciphers: Vec<Bytes> = plaintexts.iter().map(encrypt).collect();
     let decrypts = attack(ciphers);
     manual(&decrypts);
-    for row in decrypts {
-        println!(
-            "[okay] Challenge 19: {}",
-            Bytes(row.borrow().to_vec()).to_utf8()
-        );
-        break;
-    }
+    let first_line = Bytes(decrypts[0].borrow().to_vec()).to_utf8();
+    println!("[okay] Challenge 19: {first_line}");
 }
 
 pub fn challenge20() {
@@ -273,7 +269,7 @@ pub fn challenge20() {
     let plaintexts = utils::read_base64_lines("data/20.txt");
     let key = Bytes::from_utf8("YELLOW SUBMARINE");
     let encrypt = |plaintext: &Bytes| -> Bytes { ctr::encrypt(&key, 0, plaintext) };
-    let ciphers: Vec<Bytes> = plaintexts.iter().map(|ct| encrypt(&ct)).collect();
+    let ciphers: Vec<Bytes> = plaintexts.iter().map(encrypt).collect();
     let plaintexts = attack(ciphers);
 
     println!("[okay] Challenge 20: {}", plaintexts[0].to_utf8());
@@ -287,8 +283,8 @@ pub fn challenge21() {
     ];
     let mut mt = mt19937::MT19937::new();
     mt.seed(5489);
-    for i in 0..expected.len() {
-        assert_eq!(mt.extract_number(), expected[i]);
+    for e in expected {
+        assert_eq!(mt.extract_number(), e);
     }
     println!("[okay] Challenge 21: implemented MT19937");
 }
@@ -442,7 +438,7 @@ pub fn challenge24() {
         // brute force bb!
         for key in 0..u16::MAX {
             let mut found_key = true;
-            let roundtrip = mtcipher::decrypt(key, &cipher);
+            let roundtrip = mtcipher::decrypt(key, cipher);
             // check if the last 14 chars are 'A' - if yes, we found the key
             for i in (cipher_len - 14)..cipher_len {
                 if roundtrip.0[i] != b'A' {
@@ -500,9 +496,9 @@ pub fn challenge24() {
         false
     }
 
-    assert_eq!(is_time_token(&token), true);
+    assert!(is_time_token(&token));
     let non_token = Bytes(vec![b'z', 16]);
-    assert_eq!(is_time_token(&non_token), false);
+    assert!(!is_time_token(&non_token));
 
     println!("[okay] Challenge 24: MT19937 stream cipher implemented and cracked");
 }