refactor: split-numbers generic by converting to u128

test if splitting of numbers into Vec<u8> works correctly

members/libpt-bintols/src/split_numbers.rs

@@ -3,25 +3,20 @@
 //! Sometimes, you need a large integer in the form of many bytes, so split into [u8].
 //! Rust provides
 
-use num_traits::Unsigned;
-
 /// split an integer into it's bytes, ignoring those bytes that would be all zero.
 ///
 /// If the integer is zero, the Vec contains a single null byte.
-pub fn unsigned_to_vec<T>(mut num: T) -> Vec<u8>
+pub fn unsigned_to_vec<T>(num: T) -> Vec<u8>
 where
-    T: Unsigned,
-    T: std::ops::ShrAssign<i32>,
-    T: std::cmp::PartialOrd<i32>,
-    u8: std::convert::From<T>,
-    T: Copy,
+    u128: std::convert::From<T>
 {
+    let mut num: u128 = num.into();
     if num == 0 {
         return vec![0];
     }
     let mut buf: Vec<u8> = Vec::new();
     while num > 0 {
-        buf.push(num.into());
+        buf.push(num as u8);
         num >>= 8;
     }
     buf

members/libpt-bintols/tests/split_numbers.rs

@@ -0,0 +1,35 @@
+use libpt_bintols::split_numbers::*;
+
+#[test]
+fn split_u128() {
+    let source = [16, 255, 256, 0, u128::MAX, u64::MAX as u128];
+    let correct = [
+        vec![16],
+        vec![255],
+        vec![255, 1],
+        vec![0],
+        vec![
+            255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+        ],
+        vec![255, 255, 255, 255, 255, 255, 255, 255],
+    ];
+    for (i, n) in source.iter().enumerate() {
+        assert_eq!(unsigned_to_vec(*n), correct[i]);
+    }
+}
+
+#[test]
+fn split_u64() {
+    let source = [16, 255, 256, 0, u64::MAX, u32::MAX as u64];
+    let correct = [
+        vec![16],
+        vec![255],
+        vec![255, 1],
+        vec![0],
+        vec![255, 255, 255, 255, 255, 255, 255, 255],
+        vec![255, 255, 255, 255],
+    ];
+    for (i, n) in source.iter().enumerate() {
+        assert_eq!(unsigned_to_vec(*n), correct[i]);
+    }
+}