fix partial_cmp return value for equal items

1 files changed, 13 insertions, 1 deletions

diff --git a/src/gamedata.rs b/src/gamedata.rs
index a956478..a608346 100644
--- a/src/gamedata.rs
+++ b/src/gamedata.rs
@@ -2,6 +2,7 @@
 use num_derive::FromPrimitive;
 use num_traits::FromPrimitive;
 use std::{
+    cmp::Ordering,
     fmt::{self, Display, Formatter},
     str::FromStr,
 };
@@ -372,11 +373,17 @@ macro_rules! ordering_group {
 /// Future versions might extend this order to introduce inter-wing comparisons or a full [`Ord`]
 /// instance.
 impl PartialOrd for Encounter {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
         // Keep in mind that this is a partial order, not a weak order! In particular, we cannot
         // have bosses compare as equal if they are not the same (even if that would be nice for
         // Wing 5/Wing 7).
         use Encounter::*;
+
+        // Ensure that a == b <=> a.partial_cmp(b) == Equal holds
+        if *self == *other {
+            return Some(Ordering::Equal);
+        }
+
         ordering_group!(*self, *other;
             // Raids
             [ValeGuardian, Gorseval, Sabetha];
@@ -391,6 +398,7 @@ impl PartialOrd for Encounter {
             // Nightmare CM
             [MAMA, Siax, Ensolyss];
         );
+
         None
     }
 }
@@ -1204,6 +1212,10 @@ mod tests {
         assert!(Qadim > TwinLargos);
 
         assert!(Ankka.partial_cmp(&Dragonvoid).is_none());
+
+        assert_eq!(ValeGuardian.partial_cmp(&ValeGuardian), Some(Ordering::Equal));
+        assert_eq!(Slothasor.partial_cmp(&Slothasor), Some(Ordering::Equal));
+        assert_eq!(Ai.partial_cmp(&Ai), Some(Ordering::Equal));
     }
 
     #[test]