Bug 1945593 [wpt PR 50452] - Translator: Mock the monitor option, a=testonly

Automatic update from web-platform-tests
Translator: Mock the monitor option

Implements passing AICreateMonitor to the monitor callback option. And
calls it twice with 0 and 1 progress events.

Bug: 391715395
Change-Id: I90816e6897d3b4785b0039a4d39902809eb5aa00
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6221584
Reviewed-by: Jiacheng Guo <[email protected]>
Commit-Queue: Nathan Memmott <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1415028}

--

wpt-commits: c725921c44b315781ee45ada5d73ec6701a363f4
wpt-pr: 50452

Author: Nathan Memmott

Diff for: testing/web-platform/tests/ai/translator/ai_translator_translate.tentative.https.any.js

@@ -81,3 +81,31 @@ promise_test(async t => {
     return translator.translate('hello', {signal});
   });
 }, 'Aborting AITranslator.translate().');
+
+promise_test(async t => {
+  let monitorCalled = false;
+  const progressEvents = [];
+  function monitor(m) {
+    monitorCalled = true;
+
+    m.addEventListener('downloadprogress', e => {
+      progressEvents.push(e);
+    });
+  }
+
+  await ai.translator.create(
+      {sourceLanguage: 'en', targetLanguage: 'ja', monitor});
+
+  // Monitor callback must be called.
+  assert_true(monitorCalled);
+
+  // Must have at least 2 progress events, one for 0 and one for 1.
+  assert_greater_than_equal(progressEvents.length, 2);
+  assert_equals(progressEvents.at(0).loaded, 0);
+  assert_equals(progressEvents.at(1).loaded, 1);
+
+  // All progress events must have a total of 1.
+  for (const progressEvent of progressEvents) {
+    assert_equals(progressEvent.total, 1);
+  }
+}, 'AITranslatorFactory.create() monitor option is called correctly.');