Add proper unit tests for average_ceil and average_floor

Author: althonos

benches/average.rs

@@ -135,7 +135,6 @@ where
     for &(i, j) in v {
         let rt = f(&i, &j);
         let (a, b) = (min(i, j), max(i, j));
-        println!("( {:?} + {:?} )/ 2 = {:?}", a, b, rt);
         // if both number are the same sign, check rt is in the middle
         if (a < T::zero()) == (b < T::zero()) {
             if (b - a).is_even() {
@@ -163,7 +162,6 @@ where
     for &(i, j) in v {
         let rt = f(&i, &j);
         let (a, b) = (min(i, j), max(i, j));
-        println!("{:?} + {:?} / 2 = {:?}", a, b, rt);
         // if both number are the same sign, check rt is in the middle
         if (a < T::zero()) == (b < T::zero()) {
             if (b - a).is_even() {

tests/average.rs

@@ -0,0 +1,100 @@
+extern crate num_integer;
+extern crate num_traits;
+
+macro_rules! test_average {
+    ($I:ident, $U:ident) => {
+        mod $I {
+            mod ceil {
+                use num_integer::Average;
+
+                #[test]
+                fn same_sign() {
+                    assert_eq!((14 as $I).average_ceil(&16), 15 as $I);
+                    assert_eq!((14 as $I).average_ceil(&17), 16 as $I);
+
+                    let max = $crate::std::$I::MAX;
+                    assert_eq!((max - 3).average_ceil(&(max - 1)), max - 2);
+                    assert_eq!((max - 3).average_ceil(&(max - 2)), max - 2);
+                }
+
+                #[test]
+                fn different_sign() {
+                    assert_eq!((14 as $I).average_ceil(&-4), 5 as $I);
+                    assert_eq!((14 as $I).average_ceil(&-5), 5 as $I);
+
+                    let min = $crate::std::$I::MIN;
+                    let max = $crate::std::$I::MAX;
+                    assert_eq!(min.average_ceil(&max), 0 as $I);
+                }
+            }
+
+            mod floor {
+                use num_integer::Average;
+
+                #[test]
+                fn same_sign() {
+                    assert_eq!((14 as $I).average_floor(&16), 15 as $I);
+                    assert_eq!((14 as $I).average_floor(&17), 15 as $I);
+
+                    let max = $crate::std::$I::MAX;
+                    assert_eq!((max - 3).average_floor(&(max - 1)), max - 2);
+                    assert_eq!((max - 3).average_floor(&(max - 2)), max - 3);
+                }
+
+                #[test]
+                fn different_sign() {
+                    assert_eq!((14 as $I).average_floor(&-4), 5 as $I);
+                    assert_eq!((14 as $I).average_floor(&-5), 4 as $I);
+
+                    let min = $crate::std::$I::MIN;
+                    let max = $crate::std::$I::MAX;
+                    assert_eq!(min.average_floor(&max), -1 as $I);
+                }
+            }
+        }
+
+        mod $U {
+            mod ceil {
+                use num_integer::Average;
+
+                #[test]
+                fn bounded() {
+                    assert_eq!((14 as $U).average_ceil(&16), 15 as $U);
+                    assert_eq!((14 as $U).average_ceil(&17), 16 as $U);
+                }
+
+                #[test]
+                fn overflow() {
+                    let max = $crate::std::$U::MAX;
+                    assert_eq!((max - 3).average_ceil(&(max - 1)), max - 2);
+                    assert_eq!((max - 3).average_ceil(&(max - 2)), max - 2);
+                }
+            }
+
+            mod floor {
+                use num_integer::Average;
+
+                #[test]
+                fn bounded() {
+                    assert_eq!((14 as $U).average_floor(&16), 15 as $U);
+                    assert_eq!((14 as $U).average_floor(&17), 15 as $U);
+                }
+
+                #[test]
+                fn overflow() {
+                    let max = $crate::std::$U::MAX;
+                    assert_eq!((max - 3).average_floor(&(max - 1)), max - 2);
+                    assert_eq!((max - 3).average_floor(&(max - 2)), max - 3);
+                }
+            }
+        }
+    };
+}
+
+test_average!(i8, u8);
+test_average!(i16, u16);
+test_average!(i32, u32);
+test_average!(i64, u64);
+#[cfg(has_i128)]
+test_average!(i128, u128);
+test_average!(isize, usize);