fix(auto-thumbnail): [PKG-AUTO-THUMB-13] ignore registration after destroy

test/auto-thumbnail-registration.test.js

@@ -0,0 +1,50 @@
+import assert from 'node:assert/strict'
+// eslint-disable-next-line test/no-import-node-test -- Verify late asynchronous installation ownership.
+import test from 'node:test'
+import { autoThumbnailCandidate, autoThumbnailEnvironment } from './helpers/auto-thumbnail.js'
+
+const implementation = await autoThumbnailCandidate()
+
+for (const mode of ['retained-host', 'unavailable-host-members']) {
+  test(`Auto-thumbnail registration after destroy is inert: ${mode}`, async () => {
+    const env = autoThumbnailEnvironment(implementation)
+    env.art.isDestroy = true
+    if (mode === 'unavailable-host-members') {
+      for (const key of ['on', 'off', 'option']) {
+        Object.defineProperty(env.art, key, { get() {
+          throw new Error(`Destroyed host ${key} must not be read`)
+        } })
+      }
+    }
+    const pending = env.factory({ width: 80, number: 1 })(env.art)
+    assert.equal(typeof pending.then, 'function', 'Late registration retains the asynchronous public shape')
+    assert.deepEqual({ ...await pending }, { name: 'artplayerPluginAutoThumbnail' })
+    assert.equal([...env.listeners.values()].reduce((count, set) => count + set.size, 0), 0)
+    env.art.emit('video:loadedmetadata')
+    assert.equal(env.videos.length, 0)
+    assert.equal(env.canvases.length, 0)
+    assert.equal(env.timers.size, 0)
+    assert.equal(env.updates.length, 0)
+    assert.equal(env.urls.size, 0)
+  })
+}
+
+for (const marker of [false, undefined]) {
+  test(`Auto-thumbnail live registration remains compatible with isDestroy=${marker}`, async () => {
+    const env = autoThumbnailEnvironment(implementation)
+    if (marker !== undefined)
+      env.art.isDestroy = marker
+    await env.factory({ width: 80, number: 1 })(env.art)
+    env.art.emit('video:loadedmetadata')
+    assert.equal(env.videos.length, 1)
+    env.metadata()
+    env.seeked()
+    env.finish()
+    assert.equal(env.updates.length, 1)
+    assert.equal(env.urls.size, 1)
+    env.art.emit('destroy')
+    assert.equal(env.urls.size, 0)
+    assert.equal(env.timers.size, 0)
+    assert.equal(env.attached.size, 0)
+  })
+}