huskies: merge 913

server/src/pipeline_state/tests.rs

@@ -750,4 +750,82 @@ fn merge_failure_transition_emits_event_with_full_reason() {
     );
 }
 
+// ── Story 913: MergeFailure + MergeFailed self-loop ────────────────
+
+/// AC1: `MergeFailure + MergeFailed` is a valid self-transition — no error logged.
+#[test]
+fn merge_failure_plus_merge_failed_is_self_loop() {
+    let s = Stage::MergeFailure {
+        reason: "initial failure".into(),
+    };
+    let result = transition(
+        s,
+        PipelineEvent::MergeFailed {
+            reason: "second failure".into(),
+        },
+    );
+    assert!(
+        matches!(result, Ok(Stage::MergeFailure { .. })),
+        "MergeFailure + MergeFailed should self-loop to MergeFailure, got: {result:?}"
+    );
+}
+
+/// AC2 + AC3: applying `MergeFailed` to a story already in `MergeFailure` succeeds and
+/// the `TransitionFired::before` is `MergeFailure`, allowing callers to suppress the
+/// duplicate notification.
+#[test]
+fn repeated_merge_failure_apply_transition_no_error_no_duplicate_notification() {
+    crate::crdt_state::init_for_test();
+    crate::db::ensure_content_store();
+
+    let story_id = "99913_story_merge_failure_selfloop";
+    crate::db::write_item_with_content(
+        story_id,
+        "4_merge_failure",
+        "---\nname: MergeFailure Self-loop Test\n---\n# Story\n",
+        crate::db::ItemMeta::from_yaml("---\nname: MergeFailure Self-loop Test\n---\n# Story\n"),
+    );
+
+    // Apply a second MergeFailed to a story already in MergeFailure.
+    let fired = super::apply::apply_transition(
+        story_id,
+        PipelineEvent::MergeFailed {
+            reason: "duplicate failure".into(),
+        },
+        None,
+    )
+    .expect("MergeFailed on already-failed story should succeed without error");
+
+    // The before-stage was MergeFailure: this was a self-loop.
+    // Callers check this to decide whether to suppress the chat notification.
+    assert!(
+        matches!(fired.before, Stage::MergeFailure { .. }),
+        "fired.before should be MergeFailure (self-loop): {:?}",
+        fired.before
+    );
+    assert!(
+        matches!(fired.after, Stage::MergeFailure { .. }),
+        "fired.after should remain MergeFailure: {:?}",
+        fired.after
+    );
+
+    // Verify the CRDT stage is still 4_merge_failure.
+    let item = read_typed(story_id)
+        .expect("CRDT read should succeed")
+        .expect("item should still exist");
+    assert_eq!(
+        item.stage.dir_name(),
+        "4_merge_failure",
+        "CRDT stage should remain 4_merge_failure after self-loop"
+    );
+
+    // Simulate the caller's de-dup logic: since fired.before is already MergeFailure,
+    // no notification should be dispatched.
+    let should_notify = !matches!(fired.before, Stage::MergeFailure { .. });
+    assert!(
+        !should_notify,
+        "should_notify must be false for a self-loop to prevent duplicate notification"
+    );
+}
+
 // ── ProjectionError Display ─────────────────────────────────────────