swarm-ui: the cancel badge clears when the next turn starts

frontend/packages/swarm-ui/test/cancel.test.mjs

@@ -5,6 +5,7 @@ import {
   canCancel,
   cancelNote,
   cancelPath,
+  statusOnTurnChange,
 } from "../src/agent/terminal/cancel.ts";
 
 test("cancel is offered while the agent is in a turn, and only then", () => {
@@ -23,3 +24,26 @@ test("the note says whether a turn was stopped", () => {
   assert.equal(cancelNote(true), "turn cancelled");
   assert.equal(cancelNote(false), "nothing was running");
 });
+
+test("the answer stays after its turn ends and clears when the next starts", () => {
+  assert.equal(statusOnTurnChange("done", "thinking", "idle"), "done");
+  assert.equal(statusOnTurnChange("done", "idle", "idle"), "done");
+  assert.equal(statusOnTurnChange("done", "idle", "thinking"), "idle");
+});
+
+test("a failure clears when its turn ends, or a new one starts", () => {
+  assert.equal(statusOnTurnChange("error", "thinking", "thinking"), "error");
+  assert.equal(statusOnTurnChange("error", "thinking", "idle"), "idle");
+  assert.equal(statusOnTurnChange("error", "idle", "thinking"), "idle");
+});
+
+test("a cancel in flight is left alone", () => {
+  assert.equal(
+    statusOnTurnChange("cancelling", "thinking", "idle"),
+    "cancelling",
+  );
+  assert.equal(
+    statusOnTurnChange("cancelling", "idle", "thinking"),
+    "cancelling",
+  );
+});