From 7583599e65bca0a64ef333c2a976a8b64275b109 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Thu, 7 Feb 2019 13:44:48 +1100
Subject: [PATCH] Add tests for Slot/Epoch types

---
 eth2/types/src/lib.rs        |   3 +-
 eth2/types/src/slot_epoch.rs | 355 +++++++++++++++++++++++++++++++++++
 2 files changed, 356 insertions(+), 2 deletions(-)

diff --git a/eth2/types/src/lib.rs b/eth2/types/src/lib.rs
index 631d6fc58..519440beb 100644
--- a/eth2/types/src/lib.rs
+++ b/eth2/types/src/lib.rs
@@ -19,6 +19,7 @@ pub mod free_attestation;
 pub mod pending_attestation;
 pub mod proposal_signed_data;
 pub mod proposer_slashing;
+pub mod readers;
 pub mod shard_committee;
 pub mod shard_reassignment_record;
 pub mod slashable_vote_data;
@@ -29,8 +30,6 @@ pub mod validator;
 pub mod validator_registry;
 pub mod validator_registry_delta_block;
 
-pub mod readers;
-
 use ethereum_types::{H160, H256, U256};
 use std::collections::HashMap;
 
diff --git a/eth2/types/src/slot_epoch.rs b/eth2/types/src/slot_epoch.rs
index 692c61985..d924082fd 100644
--- a/eth2/types/src/slot_epoch.rs
+++ b/eth2/types/src/slot_epoch.rs
@@ -321,3 +321,358 @@ impl<'a> Iterator for SlotIter<'a> {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    macro_rules! new_tests {
+        ($type: ident) => {
+            #[test]
+            fn new() {
+                assert_eq!($type(0), $type::new(0));
+                assert_eq!($type(3), $type::new(3));
+                assert_eq!($type(u64::max_value()), $type::new(u64::max_value()));
+            }
+        };
+    }
+
+    macro_rules! from_into_tests {
+        ($type: ident, $other: ident) => {
+            #[test]
+            fn into() {
+                let x: $other = $type(0).into();
+                assert_eq!(x, 0);
+
+                let x: $other = $type(3).into();
+                assert_eq!(x, 3);
+
+                let x: $other = $type(u64::max_value()).into();
+                // Note: this will fail on 32 bit systems. This is expected as we don't have a proper
+                // 32-bit system strategy in place.
+                assert_eq!(x, $other::max_value());
+            }
+
+            #[test]
+            fn from() {
+                assert_eq!($type(0), $type::from(0_u64));
+                assert_eq!($type(3), $type::from(3_u64));
+                assert_eq!($type(u64::max_value()), $type::from($other::max_value()));
+            }
+        };
+    }
+
+    macro_rules! math_between_tests {
+        ($type: ident, $other: ident) => {
+            #[test]
+            fn partial_ord() {
+                let assert_partial_ord = |a: u64, partial_ord: Ordering, b: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a).partial_cmp(&other), Some(partial_ord));
+                };
+
+                assert_partial_ord(1, Ordering::Less, 2);
+                assert_partial_ord(2, Ordering::Greater, 1);
+                assert_partial_ord(0, Ordering::Less, u64::max_value());
+                assert_partial_ord(u64::max_value(), Ordering::Greater, 0);
+            }
+
+            #[test]
+            fn partial_eq() {
+                let assert_partial_eq = |a: u64, b: u64, is_equal: bool| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a).eq(&other), is_equal);
+                };
+
+                assert_partial_eq(0, 0, true);
+                assert_partial_eq(0, 1, false);
+                assert_partial_eq(1, 0, false);
+                assert_partial_eq(1, 1, true);
+
+                assert_partial_eq(u64::max_value(), u64::max_value(), true);
+                assert_partial_eq(0, u64::max_value(), false);
+                assert_partial_eq(u64::max_value(), 0, false);
+            }
+
+            #[test]
+            fn add_and_add_assign() {
+                let assert_add = |a: u64, b: u64, result: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a) + other, $type(result));
+
+                    let mut add_assigned = $type(a);
+                    add_assigned += other;
+
+                    assert_eq!(add_assigned, $type(result));
+                };
+
+                assert_add(0, 1, 1);
+                assert_add(1, 0, 1);
+                assert_add(1, 2, 3);
+                assert_add(2, 1, 3);
+                assert_add(7, 7, 14);
+
+                // Addition should be saturating.
+                assert_add(u64::max_value(), 1, u64::max_value());
+                assert_add(u64::max_value(), u64::max_value(), u64::max_value());
+            }
+
+            #[test]
+            fn sub_and_sub_assign() {
+                let assert_sub = |a: u64, b: u64, result: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a) - other, $type(result));
+
+                    let mut sub_assigned = $type(a);
+                    sub_assigned -= other;
+
+                    assert_eq!(sub_assigned, $type(result));
+                };
+
+                assert_sub(1, 0, 1);
+                assert_sub(2, 1, 1);
+                assert_sub(14, 7, 7);
+                assert_sub(u64::max_value(), 1, u64::max_value() - 1);
+                assert_sub(u64::max_value(), u64::max_value(), 0);
+
+                // Subtraction should be saturating
+                assert_sub(0, 1, 0);
+                assert_sub(1, 2, 0);
+            }
+
+            #[test]
+            fn mul_and_mul_assign() {
+                let assert_mul = |a: u64, b: u64, result: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a) * other, $type(result));
+
+                    let mut mul_assigned = $type(a);
+                    mul_assigned *= other;
+
+                    assert_eq!(mul_assigned, $type(result));
+                };
+
+                assert_mul(2, 2, 4);
+                assert_mul(1, 2, 2);
+                assert_mul(0, 2, 0);
+
+                // Multiplication should be saturating.
+                assert_mul(u64::max_value(), 2, u64::max_value());
+            }
+
+            #[test]
+            fn div_and_div_assign() {
+                let assert_div = |a: u64, b: u64, result: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a) / other, $type(result));
+
+                    let mut div_assigned = $type(a);
+                    div_assigned /= other;
+
+                    assert_eq!(div_assigned, $type(result));
+                };
+
+                assert_div(0, 2, 0);
+                assert_div(2, 2, 1);
+                assert_div(100, 50, 2);
+                assert_div(128, 2, 64);
+                assert_div(u64::max_value(), 2, 2_u64.pow(63) - 1);
+            }
+
+            #[test]
+            #[should_panic]
+            fn div_panics_with_divide_by_zero() {
+                let other: $other = $type(0).into();
+                let _ = $type(2) / other;
+            }
+
+            #[test]
+            #[should_panic]
+            fn div_assign_panics_with_divide_by_zero() {
+                let other: $other = $type(0).into();
+                let mut assigned = $type(2);
+                assigned /= other;
+            }
+
+            #[test]
+            fn rem() {
+                let assert_rem = |a: u64, b: u64, result: u64| {
+                    let other: $other = $type(b).into();
+                    assert_eq!($type(a) % other, $type(result));
+                };
+
+                assert_rem(3, 2, 1);
+                assert_rem(40, 2, 0);
+                assert_rem(10, 100, 10);
+                assert_rem(302042, 3293, 2379);
+            }
+        };
+    }
+
+    macro_rules! math_tests {
+        ($type: ident) => {
+            #[test]
+            fn saturating_sub() {
+                let assert_saturating_sub = |a: u64, b: u64, result: u64| {
+                    assert_eq!($type(a).saturating_sub($type(b)), $type(result));
+                };
+
+                assert_saturating_sub(1, 0, 1);
+                assert_saturating_sub(2, 1, 1);
+                assert_saturating_sub(14, 7, 7);
+                assert_saturating_sub(u64::max_value(), 1, u64::max_value() - 1);
+                assert_saturating_sub(u64::max_value(), u64::max_value(), 0);
+
+                // Subtraction should be saturating
+                assert_saturating_sub(0, 1, 0);
+                assert_saturating_sub(1, 2, 0);
+            }
+
+            #[test]
+            fn checked_div() {
+                let assert_checked_div = |a: u64, b: u64, result: Option<u64>| {
+                    let division_result_as_u64 = match $type(a).checked_div($type(b)) {
+                        None => None,
+                        Some(val) => Some(val.as_u64()),
+                    };
+                    assert_eq!(division_result_as_u64, result);
+                };
+
+                assert_checked_div(0, 2, Some(0));
+                assert_checked_div(2, 2, Some(1));
+                assert_checked_div(100, 50, Some(2));
+                assert_checked_div(128, 2, Some(64));
+                assert_checked_div(u64::max_value(), 2, Some(2_u64.pow(63) - 1));
+
+                assert_checked_div(2, 0, None);
+                assert_checked_div(0, 0, None);
+                assert_checked_div(u64::max_value(), 0, None);
+            }
+
+            #[test]
+            fn is_power_of_two() {
+                let assert_is_power_of_two = |a: u64, result: bool| {
+                    assert_eq!(
+                        $type(a).is_power_of_two(),
+                        result,
+                        "{}.is_power_of_two() != {}",
+                        a,
+                        result
+                    );
+                };
+
+                assert_is_power_of_two(0, false);
+                assert_is_power_of_two(1, true);
+                assert_is_power_of_two(2, true);
+                assert_is_power_of_two(3, false);
+                assert_is_power_of_two(4, true);
+
+                assert_is_power_of_two(2_u64.pow(4), true);
+                assert_is_power_of_two(u64::max_value(), false);
+            }
+
+            #[test]
+            fn ord() {
+                let assert_ord = |a: u64, ord: Ordering, b: u64| {
+                    assert_eq!($type(a).cmp(&$type(b)), ord);
+                };
+
+                assert_ord(1, Ordering::Less, 2);
+                assert_ord(2, Ordering::Greater, 1);
+                assert_ord(0, Ordering::Less, u64::max_value());
+                assert_ord(u64::max_value(), Ordering::Greater, 0);
+            }
+        };
+    }
+
+    macro_rules! ssz_tests {
+        ($type: ident) => {
+            #[test]
+            pub fn test_ssz_round_trip() {
+                let mut rng = XorShiftRng::from_seed([42; 16]);
+                let original = $type::random_for_test(&mut rng);
+
+                let bytes = ssz_encode(&original);
+                let (decoded, _) = $type::ssz_decode(&bytes, 0).unwrap();
+
+                assert_eq!(original, decoded);
+            }
+
+            #[test]
+            pub fn test_hash_tree_root() {
+                let mut rng = XorShiftRng::from_seed([42; 16]);
+                let original = $type::random_for_test(&mut rng);
+
+                let result = original.hash_tree_root();
+
+                assert_eq!(result.len(), 32);
+                // TODO: Add further tests
+                // https://github.com/sigp/lighthouse/issues/170
+            }
+        };
+    }
+
+    macro_rules! all_tests {
+        ($type: ident) => {
+            new_tests!($type);
+            math_between_tests!($type, $type);
+            math_tests!($type);
+            ssz_tests!($type);
+
+            mod u64_tests {
+                use super::*;
+
+                from_into_tests!($type, u64);
+                math_between_tests!($type, u64);
+
+                #[test]
+                pub fn as_64() {
+                    let x = $type(0).as_u64();
+                    assert_eq!(x, 0);
+
+                    let x = $type(3).as_u64();
+                    assert_eq!(x, 3);
+
+                    let x = $type(u64::max_value()).as_u64();
+                    assert_eq!(x, u64::max_value());
+                }
+            }
+
+            mod usize_tests {
+                use super::*;
+
+                from_into_tests!($type, usize);
+
+                #[test]
+                pub fn as_usize() {
+                    let x = $type(0).as_usize();
+                    assert_eq!(x, 0);
+
+                    let x = $type(3).as_usize();
+                    assert_eq!(x, 3);
+
+                    let x = $type(u64::max_value()).as_usize();
+                    assert_eq!(x, usize::max_value());
+                }
+            }
+        };
+    }
+
+    #[cfg(test)]
+    mod slot_tests {
+        use super::*;
+        use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
+        use ssz::ssz_encode;
+
+        all_tests!(Slot);
+    }
+
+    #[cfg(test)]
+    mod epoch_tests {
+        use super::*;
+        use crate::test_utils::{SeedableRng, TestRandom, XorShiftRng};
+        use ssz::ssz_encode;
+
+        all_tests!(Epoch);
+    }
+}