Add some tests

src/num.rs

@@ -156,4 +156,10 @@ mod tests {
         assert_eq!(u8::gcd(2, 2), 2);
         assert_eq!(u16::gcd(36, 48), 12);
     }
+
+    #[test]
+    fn test_lcm() {
+        assert_eq!(usize::lcm(15, 30), 30);
+        assert_eq!(u128::lcm(1, 5), 5);
+    }
 }

src/rational.rs

@@ -53,7 +53,8 @@ impl<T: Unsigned> Frac<T> {
 }
 
 macro_rules! impl_mul {
-    ($Type: ty) => {
+    ($( $Type: ty ),* ) => {
+        $(
             impl Mul for Frac<$Type> {
                 type Output = Self;
 
@@ -69,13 +70,10 @@ macro_rules! impl_mul {
                     }
                 }
             }
+        )*
     };
 }
-impl_mul!(u8);
-impl_mul!(u16);
-impl_mul!(u32);
-impl_mul!(u64);
-impl_mul!(usize);
+impl_mul!(u8, u16, u32, u64, usize, u128);
 
 impl<T: Unsigned> Neg for Frac<T> {
     type Output = Self;
@@ -89,4 +87,16 @@ impl<T: Unsigned> Neg for Frac<T> {
 }
 
 #[cfg(test)]
-mod tests {}
+mod tests {
+    use super::*;
+
+    #[test]
+    fn mul_test() {
+        let frac1 = Frac::new(1u8, 3u8);
+        let frac2 = Frac::new(2u8, 3u8);
+
+        let expected = Frac::new(2u8, 9u8);
+
+        assert_eq!(frac1 * frac2, expected);
+    }
+}

src/seq.rs

@@ -5,7 +5,7 @@
 ///
 /// Can calculate up to 186 using native unsigned 128 bit integers.
 ///
-/// Example
+/// Example:
 /// ```rust
 /// use rusty_numbers::seq::fibonacci;
 ///
@@ -47,6 +47,17 @@ fn _fibonacci(n: usize, table: &mut Vec<u128>) -> Option<u128> {
 /// using a lookup table for better worst-case performance.
 ///
 /// Can calculate up to 34! using native unsigned 128 bit integers.
+///
+/// Example:
+/// ```rust
+/// use rusty_numbers::seq::{factorial, fibonacci};
+///
+/// let valid = factorial(3); // Some(6)
+/// # assert_eq!(6, valid.unwrap());
+///
+/// let invalid = factorial(35); // None
+/// # assert!(invalid.is_none());
+/// ```
 pub fn factorial(n: usize) -> Option<u128> {
     let mut table: Vec<u128> = vec![1, 1, 2];