fix(street-level): a new sequence load drops the last one's error; framing survives a detached navigation

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/layers/streetLevel/cameraFraming.js

@@ -44,7 +44,8 @@ export function createCameraFraming({ state }) {
   function frame(ticket) {
     const { position, bearing, altitude } = state.street;
     if (!ticket || !position || !state.viewer) return;
-    if (ticket.generation !== null && !navigation.reassert(ticket.generation))
+    // Detached (shell teardown) since the ticket was issued: nothing to frame for.
+    if (ticket.generation !== null && !navigation?.reassert(ticket.generation))
       return;
     const ground = groundHeightAt(position.lon, position.lat, altitude);
     // Owned before the call: starting it cancels the previous flight (ours

src/layers/streetLevel/cameraFraming.test.mjs

@@ -177,3 +177,12 @@ test('a refused claim (cockpit) does not frame the photo', () => {
   framing.frame(framing.begin());
   assert.equal(flights.length, 0);
 });
+
+test('a photo that loads after the navigation was detached does not frame', () => {
+  const { framing, state, flights } = setup({ sampled: 160 });
+  framing.attachNavigation(navigationFor(state));
+  const ticket = framing.begin();
+  framing.attachNavigation(null);
+  assert.doesNotThrow(() => framing.frame(ticket));
+  assert.equal(flights.length, 0);
+});

src/layers/streetLevel/providers/mapillary/sequences.js

@@ -131,6 +131,8 @@ export function createSequences({ state, source, parts }) {
     const controller = new AbortController();
     state.sequence.abort = controller;
     state.sequence.loading = true;
+    // An earlier sequence's error does not belong to this one.
+    state.sequence.error = null;
     notify();
     try {
       const records = await source.getSequenceImages(sequenceId, {

src/layers/streetLevel/providers/mapillary/sequences.test.mjs

@@ -101,9 +101,10 @@ test('a failed sequence load leaves no stale cones and can be retried', async ()
   assert.equal(highlights.at(-1), null);
   assert.equal(state.sequence.error, 'Sequence images unavailable');
 
-  // Clicking B again asks again.
+  // Clicking B again asks again, without the old error.
   sequences.select('B');
   assert.equal(source.calls.filter((c) => c.sequenceId === 'B').length, 2);
+  assert.equal(state.sequence.error, null, 'not shown while B loads again');
   source.last('B').resolve(records('B'));
   await settle();
   assert.deepEqual(drawn(), ['B-0', 'B-1']);