usage.tentative.https.window.js

Enable keyboard shortcuts

This test has a WPT meta file that expects 1 subtest issues.
This WPT test may be referenced by the following Test IDs:
- /ai/language-model/prompt/context/usage.tentative.https.window.html - WPT Dashboard Interop Dashboard

// META: title=Language Model Prompt Context Usage

// META: script=/resources/testdriver.js

// META: script=/resources/testdriver-vendor.js

// META: script=../../../resources/util.js

// META: timeout=long

'use strict';

promise_test(async () => {

  await ensureLanguageModel();

  const session = await createLanguageModel();

  assert_equals(session.contextUsage, 0);

  const promptUsage = await session.measureContextUsage(kTestPrompt);

  assert_greater_than(promptUsage, 0);

  const result = await session.prompt(kTestPrompt);

  assert_equals(typeof result, 'string');

  const resultUsage = await session.measureContextUsage(result);

  // The response is also appended to the session context, increasing usage.

  // Allow some margin for counted tokens vs actual requested tokens.

  // TODO(crbug.com/500479741): Add expectation precision.

  assert_approx_equals(session.contextUsage, promptUsage + resultUsage, 5);

}, 'Check contextUsage increases from a simple LanguageModel.prompt() call');