3 files changed, 48 insertions, 1 deletions
diff --git a/tests/ui/non_canonical_partial_ord_impl.fixed b/tests/ui/non_canonical_partial_ord_impl.fixed
index 23dbee5a084..6915e1984fb 100644
--- a/tests/ui/non_canonical_partial_ord_impl.fixed
+++ b/tests/ui/non_canonical_partial_ord_impl.fixed
@@ -195,3 +195,19 @@ impl PartialOrd for K {
     //~^ non_canonical_partial_ord_impl
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) }
 }
+
+// #14574, check that partial_cmp invokes other.cmp
+
+#[derive(Eq, PartialEq)]
+struct L(u32);
+
+impl Ord for L {
+    fn cmp(&self, other: &Self) -> Ordering {
+        todo!();
+    }
+}
+
+impl PartialOrd for L {
+    //~^ non_canonical_partial_ord_impl
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) }
+}
diff --git a/tests/ui/non_canonical_partial_ord_impl.rs b/tests/ui/non_canonical_partial_ord_impl.rs
index 12f055a542b..7ce4cdc9aec 100644
--- a/tests/ui/non_canonical_partial_ord_impl.rs
+++ b/tests/ui/non_canonical_partial_ord_impl.rs
@@ -201,3 +201,21 @@ impl PartialOrd for K {
         Ordering::Greater.into()
     }
 }
+
+// #14574, check that partial_cmp invokes other.cmp
+
+#[derive(Eq, PartialEq)]
+struct L(u32);
+
+impl Ord for L {
+    fn cmp(&self, other: &Self) -> Ordering {
+        todo!();
+    }
+}
+
+impl PartialOrd for L {
+    //~^ non_canonical_partial_ord_impl
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(other.cmp(self))
+    }
+}
diff --git a/tests/ui/non_canonical_partial_ord_impl.stderr b/tests/ui/non_canonical_partial_ord_impl.stderr
index c7de968588f..9bd6b1f726d 100644
--- a/tests/ui/non_canonical_partial_ord_impl.stderr
+++ b/tests/ui/non_canonical_partial_ord_impl.stderr
@@ -44,5 +44,18 @@ LL | ||     }
 LL | |  }
    | |__^
 
-error: aborting due to 3 previous errors
+error: non-canonical implementation of `partial_cmp` on an `Ord` type
+  --> tests/ui/non_canonical_partial_ord_impl.rs:216:1
+   |
+LL | /  impl PartialOrd for L {
+LL | |
+LL | |      fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+   | | _____________________________________________________________-
+LL | ||         Some(other.cmp(self))
+LL | ||     }
+   | ||_____- help: change this to: `{ Some(self.cmp(other)) }`
+LL | |  }
+   | |__^
+
+error: aborting due to 4 previous errors