Rollup merge of #126774 - nnethercote:fix-126751, r=oli-obk

Fix another assertion failure for some Expect diagnostics.

Very similar to #126719. So much so that I added a new case to the test from that PR rather than creating a new one.

r? `@oli-obk`

1 files changed, 4 insertions, 4 deletions

diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs
index 620f56c01e8..91112a57277 100644
--- a/compiler/rustc_errors/src/lib.rs
+++ b/compiler/rustc_errors/src/lib.rs
@@ -1456,10 +1456,10 @@ impl DiagCtxtInner {
         }
 
         if diagnostic.has_future_breakage() {
-            // Future breakages aren't emitted if they're `Level::Allow`,
-            // but they still need to be constructed and stashed below,
-            // so they'll trigger the must_produce_diag check.
-            assert!(matches!(diagnostic.level, Error | Warning | Allow));
+            // Future breakages aren't emitted if they're `Level::Allow` or
+            // `Level::Expect`, but they still need to be constructed and
+            // stashed below, so they'll trigger the must_produce_diag check.
+            assert!(matches!(diagnostic.level, Error | Warning | Allow | Expect(_)));
             self.future_breakage_diagnostics.push(diagnostic.clone());
         }