fix(thumbnail): [PKG-TOOL-THUMB-04] protect event names and nested once dispatch

test/browser/thumbnail-emitter.spec.js

@@ -0,0 +1,47 @@
+import { hash } from '../../refactor/scripts/releases.mjs'
+import { thumbnailCandidate } from '../helpers/thumbnail.js'
+import { expect, test } from './fixtures.js'
+
+const candidate = await thumbnailCandidate()
+
+test('Thumbnail native browser event registry handles special names and nested once without changing DOM cleanup', async ({ page }, testInfo) => {
+  await page.goto('/test/player.html?core=candidate&chapter=published')
+  await page.addScriptTag({ content: candidate.code })
+  const result = await page.evaluate(() => {
+    const input = document.createElement('input')
+    input.type = 'file'
+    document.body.append(input)
+    const tool = new ArtplayerToolThumbnail({ fileInput: input })
+    const keys = []
+    for (const name of ['__proto__', 'constructor', 'toString', 'hasOwnProperty']) {
+      let calls = 0
+      tool.emit(name)
+      const prototype = Object.getPrototypeOf(tool.e)
+      tool.on(name, () => calls++).once(name, () => calls++)
+      tool.emit(name).emit(name).off(name)
+      keys.push({ name, calls, prototypePreserved: Object.getPrototypeOf(tool.e) === prototype, removed: !Object.hasOwn(tool.e, name) })
+    }
+    let nested = false
+    const seen = []
+    tool.on('custom', value => {
+      if (!nested) {
+        nested = true
+        tool.emit('custom', 'inner')
+      }
+      seen.push(`on:${value}`)
+    })
+    tool.once('custom', value => seen.push(`once:${value}`))
+    tool.emit('custom', 'outer')
+    const video = tool.video
+    tool.destroy()
+    tool.destroy()
+    input.remove()
+    return { keys, seen, videoConnected: video.isConnected, inputConnected: input.isConnected, processing: tool.processing }
+  })
+  expect(result.keys).toEqual(['__proto__', 'constructor', 'toString', 'hasOwnProperty'].map(name => ({ name, calls: 3, prototypePreserved: true, removed: true })))
+  expect(result.seen).toEqual(['on:inner', 'once:inner', 'on:outer'])
+  expect(result.videoConnected).toBe(false)
+  expect(result.inputConnected).toBe(false)
+  expect(result.processing).toBe(false)
+  await testInfo.attach('thumbnail-emitter', { contentType: 'application/json', body: JSON.stringify({ candidate: candidate.name, sha256: hash(candidate.code), result }) })
+})