Test case for new derive(PartialOrd) expansion.

src/test/run-pass/issue-15523.rs

@@ -0,0 +1,49 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Issue 15523: derive(PartialOrd) should use the provided
+// discriminant values for the derived ordering.
+
+#[derive(PartialEq, PartialOrd)]
+enum E1 {
+    Pos2 = 2,
+    Neg1 = -1,
+    Pos1 = 1,
+}
+
+#[derive(PartialEq, PartialOrd)]
+#[repr(u8)]
+enum E2 {
+    Pos2 = 2,
+    PosMax = !0 as u8,
+    Pos1 = 1,
+}
+
+#[derive(PartialEq, PartialOrd)]
+#[repr(i8)]
+enum E3 {
+    Pos2 = 2,
+    Neg1 = -1_i8,
+    Pos1 = 1,
+}
+
+fn main() {
+    assert!(E1::Pos2 > E1::Pos1);
+    assert!(E1::Pos1 > E1::Neg1);
+    assert!(E1::Pos2 > E1::Neg1);
+
+    assert!(E2::Pos2 > E2::Pos1);
+    assert!(E2::Pos1 < E2::PosMax);
+    assert!(E2::Pos2 < E2::PosMax);
+
+    assert!(E3::Pos2 > E3::Pos1);
+    assert!(E3::Pos1 > E3::Neg1);
+    assert!(E3::Pos2 > E3::Neg1);
+}