Merge main and switch Cesium and Navara in place through Vue

Preserve the camera, map source and layer selection across engine sessions. Restore the previous engine if startup fails and retain local history navigation.

scripts/qa-engine-switch.mjs

@@ -13,7 +13,8 @@ if (
   throw new Error('Supply an unreserved local preview URL');
 }
 base.search = '?welcome=0&look=cinematic';
-base.hash = 'v=2&lat=42.3554&lon=-71.0605&alt=6000&heading=0&pitch=-90&map=osm';
+base.hash =
+  'v=2&lat=42.3554&lon=-71.0605&alt=6000&heading=0&pitch=-90&map=osm&l=e';
 const browser = await puppeteer.launch({
   headless: true,
   args: ['--use-angle=metal', '--enable-gpu'],
@@ -24,6 +25,13 @@ try {
   await installTileCache(page);
   await page.evaluateOnNewDocument(() => {
     localStorage.setItem('gev:first-run-mission:v1', 'suppressed');
+    const fetch = window.fetch.bind(window);
+    window.fetch = (url, options) =>
+      String(url).startsWith('https://earthquake.usgs.gov/earthquakes/feed/')
+        ? Promise.resolve(
+            Response.json({ type: 'FeatureCollection', features: [] }),
+          )
+        : fetch(url, options);
   });
   await page.setViewport({ width: 1280, height: 800 });
   const errors = [];
@@ -55,11 +63,22 @@ try {
       await page.keyboard.press('Enter');
     }
     await page.waitForSelector('#globe-engine', { visible: true });
-    await Promise.all([
-      page.waitForNavigation({ waitUntil: 'domcontentloaded' }),
-      page.select('#globe-engine', kind),
-    ]);
+    await page.evaluate(() => {
+      window.__switchDocument = document;
+      window.__outgoingEngine = window.__godsEyeView.engine;
+    });
+    await page.select('#globe-engine', kind);
     await ready(kind);
+    assert.ok(await page.evaluate(() => window.__switchDocument === document));
+    assert.ok(
+      await page.evaluate(
+        () =>
+          window.__outgoingEngine.isDestroyed() &&
+          window.__godsEyeView.dataManager
+            .getEnabledLayerIds()
+            .has('earthquakes'),
+      ),
+    );
     const url = new URL(page.url());
     assert.equal(url.searchParams.get('engine'), kind);
     assert.equal(url.searchParams.get('look'), 'cinematic');
@@ -89,6 +108,10 @@ try {
   assert.equal(await stored(), 'navara');
   await page.goBack({ waitUntil: 'domcontentloaded' });
   await ready('cesium');
+  await page.goForward();
+  await ready('navara');
+  await switchTo('cesium');
+  await switchTo('navara');
   await page.goto(base.href, { waitUntil: 'domcontentloaded' });
   await ready('navara');
   await switchTo('cesium');
@@ -105,7 +128,7 @@ try {
   assert.equal(await stored(), 'cesium');
   assert.deepEqual(errors, []);
   console.log(
-    'PASS Cesium default, both switches, share pose/map, Back, remembered engine, blocked preference storage',
+    'PASS Cesium default, both switches, same document, outgoing engine destroyed, share pose/map/layers, Back/Forward, remembered engine, blocked preference storage',
   );
 } finally {
   await browser.close();